WEBVTT 00:01:13.516 --> 00:01:15.526 Elevator: Which floor please? 00:01:15.539 --> 00:01:16.939 Girl: 3rd underfloor? 00:01:16.950 --> 00:01:18.400 Elevator: Thank you. 00:01:23.492 --> 00:01:25.800 Boy: Where are all the other stores? 00:01:25.800 --> 00:01:27.550 Girl: Well, I don't know really. 00:01:27.570 --> 00:01:31.570 But I do know that the store helped Caysie win first prize at the science fair. 00:01:31.850 --> 00:01:33.320 Boy: The store did THAT? 00:01:33.913 --> 00:01:36.191 Girl: Well, the person who works there did. 00:01:36.191 --> 00:01:38.011 Her name is Mrs. Molly Mcqule. 00:01:38.081 --> 00:01:38.831 (giggles) 00:01:39.451 --> 00:01:40.539 You can laugh if you want, 00:01:40.539 --> 00:01:44.289 but weren't you the one that needed help in science class? 00:01:44.336 --> 00:01:47.546 Yes, I guess. My grades haven't been all that great. 00:01:47.587 --> 00:01:49.827 And we're starting to study matter. 00:01:56.930 --> 00:01:57.940 Girl: Mrs. Mcqule 00:02:01.221 --> 00:02:02.291 Mrs. Mcqule: May I help you? 00:02:02.291 --> 00:02:03.871 Girl: Mrs.Mcqule.. It's me Amanda, 00:02:03.871 --> 00:02:05.661 You helped my friend with his science project, 00:02:06.321 --> 00:02:07.601 And well Kyle here. 00:02:08.389 --> 00:02:10.389 Mrs.Mcqule: As a matter of fact I can. 00:02:10.389 --> 00:02:11.189 Kyle: What? 00:02:11.417 --> 00:02:13.137 Mrs. Mcqule: The facts of matter. 00:02:13.137 --> 00:02:14.177 One second please. 00:02:14.257 --> 00:02:24.477 (Weird sounds) 00:02:24.952 --> 00:02:26.559 Mrs. Mcqule: Is there something I can show you in matter? 00:02:26.559 --> 00:02:27.469 Amanda: Mmm yeah. 00:02:27.469 --> 00:02:30.029 My friend Kyle's having some problems in class. 00:02:30.029 --> 00:02:31.499 They're studying matter. 00:02:31.499 --> 00:02:34.229 Kyle: Yeah. The properties and changes of matter. 00:02:34.229 --> 00:02:35.299 Can you help? 00:02:35.513 --> 00:02:37.763 Mrs. Mcqule: As a matter of fact I can. 00:02:38.043 --> 00:02:39.483 Don't you just love that? 00:02:39.483 --> 00:02:41.723 (Jokes around) Matter, facts.. get it? 00:02:41.723 --> 00:02:43.283 Ehh nevermind.. NOTE Paragraph 00:02:43.283 --> 00:02:45.328 Anyway, let's review what matter is. 00:02:45.328 --> 00:02:46.188 Amanda? 00:02:46.188 --> 00:02:48.718 Amanda: Matter is anything that takes up space.. 00:02:48.718 --> 00:02:51.008 has mass and has properties that you 00:02:51.008 --> 00:02:53.358 can observe and describe. 00:02:53.358 --> 00:02:54.978 Kyle: But, what is a property? 00:02:55.497 --> 00:02:57.447 Amanda: A property is something special 00:02:57.447 --> 00:02:59.537 about an object. That makes it what it is. 00:02:59.756 --> 00:03:01.406 Like this bell, it's metal. 00:03:02.513 --> 00:03:03.603 Kyle: Oh, I get it. 00:03:04.020 --> 00:03:06.260 Mrs. Mcqule: Splendid! Blue star for you. 00:03:06.754 --> 00:03:08.690 I think you're really gonna like this. 00:03:08.690 --> 00:03:10.480 I just bought the upgrade. (Claps) 00:03:11.618 --> 00:03:13.228 Now, let's proceed. 00:03:14.130 --> 00:03:15.210 Computer voice: Matter is made up of 00:03:15.210 --> 00:03:16.320 elements 00:03:16.320 --> 00:03:18.405 or pure substances that are often called 00:03:18.405 --> 00:03:20.445 the building blocks of matter. 00:03:20.481 --> 00:03:22.261 And these building blocks are made up of 00:03:22.391 --> 00:03:24.331 small particles called atoms. 00:03:25.694 --> 00:03:27.504 Now each type of matter has its own 00:03:27.504 --> 00:03:29.654 physical properties. Which makes it 00:03:29.654 --> 00:03:31.504 different from other types of matter. 00:03:32.546 --> 00:03:34.656 Physical properties can be measured 00:03:34.656 --> 00:03:36.576 or observed without changing the 00:03:36.576 --> 00:03:38.176 matter into something else. 00:03:38.529 --> 00:03:40.989 Most of these properties remain consant 00:03:40.989 --> 00:03:43.249 and can be used to identify it. 00:03:44.279 --> 00:03:46.729 Now some properties are common to 00:03:46.729 --> 00:03:49.679 or found in all types of matter. 00:03:50.575 --> 00:03:52.575 All matter has mass, which is the 00:03:52.575 --> 00:03:54.615 amount of matter in an object. 00:03:55.764 --> 00:03:58.214 For example, an object with a large 00:03:58.214 --> 00:03:59.684 mass feels heavy. 00:04:00.723 --> 00:04:02.493 While an object with a small mass 00:04:02.493 --> 00:04:03.223 feels light. 00:04:04.800 --> 00:04:06.740 So you simply can't tell how much 00:04:06.740 --> 00:04:09.170 mass an object has just by looking at it. 00:04:09.734 --> 00:04:11.414 But you can measure it. 00:04:13.020 --> 00:04:15.510 Mrs.Mcqule: All matter also has volume 00:04:15.510 --> 00:04:17.350 which is the amount of space an 00:04:17.350 --> 00:04:19.740 object takes up. This ballon for example 00:04:19.740 --> 00:04:21.810 has more volume than.. say a 00:04:21.810 --> 00:04:24.820 golf ball. Because it takes up more space. 00:04:25.127 --> 00:04:27.777 I mean kids, it's just bigger. 00:04:29.018 --> 00:04:31.798 And all matter has density. Which is 00:04:31.798 --> 00:04:34.228 the property of matter that compares 00:04:34.228 --> 00:04:36.778 the mass, the amount of matter. 00:04:36.778 --> 00:04:40.188 To volume, the space it takes up. 00:04:40.488 --> 00:04:43.428 Kyle: So all matter has is physical properties. 00:04:43.428 --> 00:04:45.588 Well what about changes in matter? 00:04:45.608 --> 00:04:47.598 Mrs.Mcqule: Patience dear boy. Let's 00:04:47.598 --> 00:04:49.018 take a look at physical properties 00:04:49.018 --> 00:04:51.048 first and then we'll dive right in and 00:04:51.048 --> 00:04:52.128 solve your problem, ok? 00:04:52.521 --> 00:04:54.631 The atoms that come together to make 00:04:54.631 --> 00:04:58.631 up that matter give it it's particular physical properties. 00:04:59.988 --> 00:05:01.928 Computer voice: One physical property that's 00:05:01.928 --> 00:05:03.818 found in most matter is that it is, 00:05:03.818 --> 00:05:04.518 metallic. 00:05:05.594 --> 00:05:09.017 84 out of 112 known elements are metallic. 00:05:09.545 --> 00:05:10.675 That's 3/4's. 00:05:11.750 --> 00:05:14.125 In fact all elements can be divided into 00:05:14.125 --> 00:05:17.885 metallic and non-metallic elements. 00:05:19.075 --> 00:05:27.365 Elements like copper, gold, silver, aluminum 00:05:27.365 --> 00:05:31.375 iron, and nickel are metallic. 00:05:32.489 --> 00:05:36.699 All metals except mercury are solid at room temperature. 00:05:37.019 --> 00:05:39.469 Also, most metals look shiny and are 00:05:39.469 --> 00:05:41.289 found in the Earths ground. 00:05:42.499 --> 00:05:45.119 Most metals are said to be malleable 00:05:45.119 --> 00:05:47.089 which means that they can be 00:05:47.089 --> 00:05:48.699 hammered into thin sheets. 00:05:48.799 --> 00:05:51.369 Or pulled into long thin wires. 00:05:52.457 --> 00:05:55.157 Some metals are light, they are bendable 00:05:55.157 --> 00:05:57.147 like copper and aluminum. 00:05:57.147 --> 00:05:58.907 That are used to make wire. 00:05:59.755 --> 00:06:02.725 Some metals like iron are heavy, hard 00:06:02.725 --> 00:06:04.265 and very strong. 00:06:05.727 --> 00:06:08.657 Kyle: So matter that is metallic is usually 00:06:08.657 --> 00:06:11.727 shiny, solid at room temperature, 00:06:11.727 --> 00:06:13.407 malleable and strong. 00:06:14.463 --> 00:06:16.603 Mrs. Mcqule: You're a quick learner. 00:06:16.603 --> 00:06:20.603 Now 28 or 1/4 of all elements are 00:06:20.603 --> 00:06:23.973 classified as non-metals and their 00:06:23.973 --> 00:06:26.003 properties are very different from the 00:06:26.003 --> 00:06:27.083 properties of metals. 00:06:27.530 --> 00:06:28.170 Amanda: Like what? 00:06:28.546 --> 00:06:30.736 Mrs: Mcqule: Well, most non-metals are 00:06:30.736 --> 00:06:32.856 not shiny and can not be hammered into 00:06:32.856 --> 00:06:35.136 sheets or pulled into a wire. They are not 00:06:35.136 --> 00:06:37.406 malleable they are brittle. 00:06:38.165 --> 00:06:41.505 Oxygen and nitrogen are non-metals 00:06:41.505 --> 00:06:43.905 that are in the air. (blows) 00:06:44.808 --> 00:06:48.808 Carbon, a solid non-metal is dark. 00:06:49.637 --> 00:06:52.097 Now that we've established metals and 00:06:52.097 --> 00:06:53.897 non-metals. Let's say we take a look at 00:06:53.897 --> 00:06:55.817 some of the more exciting physical 00:06:55.817 --> 00:06:56.067 properties. 00:06:56.518 --> 00:06:59.078 Matter has an physical property called 00:06:59.078 --> 00:07:00.208 conductivity. 00:07:02.223 --> 00:07:03.853 Computer voice: Conductivity is the 00:07:03.853 --> 00:07:06.283 ability to pass energy along from one 00:07:06.283 --> 00:07:07.683 particle to another. 00:07:08.548 --> 00:07:10.618 There are three kinds of conductivity 00:07:10.618 --> 00:07:16.268 electrical, heat and sound. 00:07:18.088 --> 00:07:23.848 (background music) 00:07:25.466 --> 00:07:27.536 When matter can move electrical energy 00:07:27.536 --> 00:07:29.716 from one particle to another it is called 00:07:29.716 --> 00:07:33.416 an electrical conductor, metals used to 00:07:33.416 --> 00:07:36.306 make wire such as those made of copper 00:07:36.306 --> 00:07:37.476 are electrical conductors. 00:07:38.520 --> 00:07:40.510 The reason these metals are able to 00:07:40.510 --> 00:07:42.470 conduct electricity, is that the electrons 00:07:42.470 --> 00:07:44.770 fartest from the nucleus of a metal atom 00:07:44.770 --> 00:07:47.870 are only held lightly by that atom 00:07:47.870 --> 00:07:50.520 they are free to move to other metal atoms. 00:07:51.460 --> 00:07:53.620 This freedom of electron movement, 00:07:53.620 --> 00:07:55.590 allows metal to conduct electricity. 00:07:56.777 --> 00:07:59.097 Matter that is unable to conduct much 00:07:59.097 --> 00:08:01.127 electricity at all is called an 00:08:01.127 --> 00:08:03.437 Electric Insulator. 00:08:04.183 --> 00:08:05.913 This matter in non-metallic. 00:08:06.943 --> 00:08:09.523 In electric insulators, the electrons are 00:08:09.523 --> 00:08:11.163 bound tightly to their atoms. 00:08:12.916 --> 00:08:15.286 Glass, plastic and rubber are good examples. 00:08:17.029 --> 00:08:21.499 (background music) 00:08:23.394 --> 00:08:25.574 Some materials can conduct heat very 00:08:25.574 --> 00:08:25.884 well. 00:08:27.184 --> 00:08:29.204 These materials allow heat to flow 00:08:29.204 --> 00:08:30.144 through them easily. 00:08:31.694 --> 00:08:34.184 Metals conduct or transfer heat very quickly. 00:08:37.345 --> 00:08:39.315 For instance, have you ever noticed 00:08:39.315 --> 00:08:41.135 that when a car has been sitting in the 00:08:41.135 --> 00:08:44.115 sun, it's metal parts are much hotter than 00:08:44.115 --> 00:08:45.425 its plastic parts. 00:08:46.746 --> 00:08:48.596 That's because metal conducts heat 00:08:48.596 --> 00:08:50.586 better than non-metal plastic. 00:08:50.842 --> 00:08:57.922 (background music) 00:08:58.858 --> 00:09:00.938 Cooking pots and pans are made of metal. 00:09:02.661 --> 00:09:04.421 Because metal conducts heat well. 00:09:05.609 --> 00:09:07.609 The heat from the stove is quickly passed 00:09:07.609 --> 00:09:09.439 through the pan, into the food. 00:09:11.101 --> 00:09:13.031 Voila! The food is cooked. 00:09:16.347 --> 00:09:18.737 Other materials insulate against the 00:09:18.737 --> 00:09:19.627 passage of heat. 00:09:19.627 --> 00:09:20.834 Man: Ooh la la! 00:09:21.587 --> 00:09:22.997 Mrs.Mqcule: Which means that they do 00:09:22.997 --> 00:09:24.797 not readily permit heat to flow. 00:09:25.217 --> 00:09:26.127 (Glass shatters) 00:09:26.127 --> 00:09:27.857 Cooking pots should have wooden or 00:09:27.857 --> 00:09:30.747 plastic handles to insulate against heat. 00:09:30.822 --> 00:09:33.472 So you don't get burned when you touch them. 00:09:33.771 --> 00:09:39.731 (background music) 00:09:40.800 --> 00:09:43.400 This last kind of conduction is a bit 00:09:43.400 --> 00:09:44.610 different. 00:09:44.872 --> 00:09:47.302 This is the movement of sound energy. 00:09:48.188 --> 00:09:49.428 (Bell rings) 00:09:49.708 --> 00:09:52.168 Many metallic substances conduct sound 00:09:52.168 --> 00:09:53.228 very well. 00:09:54.026 --> 00:09:58.046 But a non-metallic substance, like glass 00:09:58.666 --> 00:10:01.426 or even water conduct sound well too. 00:10:02.397 --> 00:10:04.157 Matter with a poor ability to conduct 00:10:04.157 --> 00:10:06.617 sound is used as sound insulation. 00:10:08.312 --> 00:10:10.662 Special ceiling tiles are good examples 00:10:10.662 --> 00:10:11.462 of this. 00:10:13.298 --> 00:10:15.848 Mrs.Mcqule: Whether or not a substance is 00:10:15.848 --> 00:10:19.128 magnetic, is another physical property of 00:10:19.338 --> 00:10:20.008 matter. 00:10:20.722 --> 00:10:22.982 Objects made from iron and steel are 00:10:24.752 --> 00:10:25.782 magnetic. 00:10:26.682 --> 00:10:27.472 Plastic is not. 00:10:28.643 --> 00:10:30.793 Well we can't mention physical properties 00:10:30.793 --> 00:10:32.823 of matter without mentioning chemical 00:10:32.823 --> 00:10:33.533 properties as well. 00:10:33.869 --> 00:10:35.449 Kyle: Yeah. I'm about to study that in 00:10:35.449 --> 00:10:35.739 class. 00:10:36.264 --> 00:10:37.764 Mrs.Mcqule: Mmmm, how about a head start? 00:10:38.932 --> 00:10:41.132 Computer voice: Chemical properties 00:10:41.132 --> 00:10:42.062 describe the ability of matter 00:10:42.062 --> 00:10:43.582 to react or combine with 00:10:43.582 --> 00:10:46.782 another matter to form a new substance, 00:10:46.782 --> 00:10:48.002 a new kind of matter. 00:10:49.222 --> 00:10:51.182 Although it's pretty hard to observe a 00:10:51.182 --> 00:10:53.032 chemical property. 00:10:53.385 --> 00:10:56.365 For example, pyrite and gold look a lot 00:10:56.365 --> 00:10:59.335 alike, but pyrite is made of iron and 00:10:59.335 --> 00:11:00.935 sulfur atoms. 00:11:01.376 --> 00:11:03.606 It has some of the physical properties 00:11:03.606 --> 00:11:06.096 of gold, but it's fools gold. 00:11:07.678 --> 00:11:10.088 People sometimes use acid to tell gold 00:11:10.088 --> 00:11:11.208 and pyrite apart. 00:11:12.940 --> 00:11:15.200 The sulfur in pyrite reacts with the acid 00:11:15.200 --> 00:11:19.170 to produce a gas gold does not. 00:11:21.193 --> 00:11:23.103 Another chemical property is the ability 00:11:23.103 --> 00:11:23.683 to burn. 00:11:24.490 --> 00:11:25.830 This is called combustibility. 00:11:27.341 --> 00:11:29.431 Flame tests can be used to identify 00:11:29.431 --> 00:11:31.931 substances based on the color of the flame 00:11:31.931 --> 00:11:33.221 they produce when burned. 00:11:34.676 --> 00:11:36.746 Barium produces a green flame. 00:11:38.003 --> 00:11:39.923 Sodium produces a yellow flame. 00:11:41.304 --> 00:11:43.344 And potassium produces a violet flame. 00:11:44.653 --> 00:11:49.573 (background music) 00:11:49.783 --> 00:11:51.803 And now Kyle as for your request 00:11:51.803 --> 00:11:54.473 the changes of matter physically and 00:11:54.473 --> 00:11:55.963 chemically that is. 00:11:56.762 --> 00:11:58.472 Why don't we start with physical change, 00:11:58.472 --> 00:12:02.392 which is a change in state, shape or size 00:12:02.611 --> 00:12:04.521 without forming a new substance. 00:12:05.755 --> 00:12:07.665 A change in the state of matter is 00:12:07.665 --> 00:12:08.445 a physical change. 00:12:10.187 --> 00:12:12.527 For example, when water changes state 00:12:12.527 --> 00:12:15.117 it looks and feels different, but it is 00:12:15.117 --> 00:12:16.357 still water. 00:12:16.998 --> 00:12:20.998 Whether it's ice, liquid or vapor. 00:12:21.652 --> 00:12:23.382 Let's run with this, shall we? 00:12:24.433 --> 00:12:31.093 When you grind peanuts.. you get peanut 00:12:31.093 --> 00:12:31.793 butter. 00:12:32.534 --> 00:12:34.754 The size and shape have changed, but 00:12:34.754 --> 00:12:35.604 you still have peanuts. 00:12:37.322 --> 00:12:40.662 Remember a change in size or shape 00:12:40.662 --> 00:12:42.952 is a physical change, no new substances 00:12:42.952 --> 00:12:43.252 formed. 00:12:44.525 --> 00:12:46.845 Other physical changes include mixing 00:12:46.845 --> 00:12:49.375 together two or more kinds of matter. 00:12:49.375 --> 00:12:51.785 Or separating matter into the different 00:12:51.785 --> 00:12:55.205 parts as long as no new substances formed 00:12:57.710 --> 00:12:59.790 Most of the objects around us are not 00:12:59.790 --> 00:13:02.670 pure substances, but mixtures. 00:13:02.670 --> 00:13:05.590 A mixture is two or more parts blended 00:13:05.590 --> 00:13:10.620 together, yet they keep their own properties 00:13:10.620 --> 00:13:12.370 and do not turn into a new substance. 00:13:12.988 --> 00:13:14.828 In some mixtures it's easy to tell 00:13:14.828 --> 00:13:16.968 that each type of matter keeps its 00:13:16.968 --> 00:13:19.208 physical properties, because you can still 00:13:19.208 --> 00:13:21.728 see the individual parts of the mixture. 00:13:22.298 --> 00:13:24.308 Examples of this could be salad, 00:13:25.178 --> 00:13:32.198 spaghetti, tacos, and trail mix. 00:13:33.583 --> 00:13:36.003 In other mixtures the parts are hard to see. 00:13:36.645 --> 00:13:39.175 Like sugar or salt mixed with water. 00:13:40.873 --> 00:13:43.053 Also, in a mixture you can put the 00:13:43.053 --> 00:13:45.283 substances together in any amount. 00:13:46.313 --> 00:13:48.963 For example, tea can be very strong 00:13:48.963 --> 00:13:50.363 or very weak. 00:13:51.731 --> 00:13:54.271 Mixtures can be made of solids, liquids 00:13:54.271 --> 00:13:57.731 or gases and can be made with a 00:13:57.731 --> 00:13:59.971 combination of different forms of matter. 00:13:59.971 --> 00:14:02.401 Air is a mixture of different gases. 00:14:04.496 --> 00:14:06.356 Mixtures can also be separated using 00:14:06.356 --> 00:14:08.926 their physical properties like size, shape, 00:14:08.926 --> 00:14:11.956 color, volume, density and state. 00:14:14.170 --> 00:14:16.350 This is called a physical separation. 00:14:17.971 --> 00:14:20.081 It's important to remember that subsatnces 00:14:20.081 --> 00:14:21.751 that make up mixtures; keep their 00:14:21.751 --> 00:14:24.331 physical properties as well as their 00:14:24.331 --> 00:14:25.621 chemical properties. 00:14:26.765 --> 00:14:29.095 Some mixtures are not as easily separated. 00:14:29.095 --> 00:14:31.525 These "hard-to-separate" mixtures are 00:14:31.525 --> 00:14:32.645 called solutions. 00:14:34.522 --> 00:14:36.932 A solution is a mixture in which 00:14:36.932 --> 00:14:39.021 substances are completely blended, 00:14:39.021 --> 00:14:40.591 so that the properties are the same 00:14:40.591 --> 00:14:40.921 throughout. 00:14:42.673 --> 00:14:44.613 The substances are mixed evenly, so they 00:14:44.613 --> 00:14:46.353 stay blended. 00:14:47.464 --> 00:14:49.604 If you put a spoonful of sugar into a 00:14:49.604 --> 00:14:52.744 glass of liquid water and stir; the sugar 00:14:52.744 --> 00:14:54.934 seems to disappear and the glass still 00:14:54.934 --> 00:14:56.394 contains a clear liquid. 00:14:57.450 --> 00:14:59.380 The sugar and the water form a kind 00:14:59.380 --> 00:15:01.520 of mixture called a solution. 00:15:02.774 --> 00:15:04.974 Although you can't see it, you can tell 00:15:05.163 --> 00:15:07.503 the sugar's in the water, because it tastes 00:15:07.503 --> 00:15:07.763 sweet. 00:15:09.110 --> 00:15:11.410 When the water evaporates, the sugar 00:15:11.410 --> 00:15:13.610 will be left behind and you can see it 00:15:13.610 --> 00:15:14.190 again. 00:15:15.423 --> 00:15:17.433 People drink a lot of types of solutions, 00:15:17.553 --> 00:15:20.933 like tea, coffee, fruit juices, and soft 00:15:20.933 --> 00:15:21.193 drinks. 00:15:22.544 --> 00:15:24.674 When one material forms a solution 00:15:24.674 --> 00:15:28.494 with another material; we say it dissolves. 00:15:28.568 --> 00:15:31.078 The substance in a solution dissolve or 00:15:31.467 --> 00:15:33.397 separate into their most basic particles. 00:15:34.759 --> 00:15:36.989 Molecules that are too small to be seen. 00:15:38.197 --> 00:15:40.627 As sugar dissolves in water, molecules of 00:15:40.627 --> 00:15:42.617 solid sugar are pulled away from 00:15:42.617 --> 00:15:44.477 eachother by water molecules. 00:15:45.726 --> 00:15:47.456 Very quickly the sugar molecules 00:15:47.456 --> 00:15:49.496 spread to all parts of the solution. 00:15:50.599 --> 00:15:52.369 You can no longer see the sugar, 00:15:52.379 --> 00:15:54.719 because the very small sugar particles 00:15:54.719 --> 00:15:57.219 are mixed evenly with the water particles. 00:15:58.329 --> 00:16:00.729 Unlike the mixture of granola, that might 00:16:00.729 --> 00:16:02.859 have six raisins in one spoonful 00:16:03.059 --> 00:16:04.419 and three in the next. 00:16:05.504 --> 00:16:07.854 Any part of the solution is identical to 00:16:07.854 --> 00:16:09.664 any other part of the solution. 00:16:10.771 --> 00:16:12.921 Some solids dissolve in water and some 00:16:12.921 --> 00:16:13.341 do not. 00:16:14.463 --> 00:16:16.753 Solubility is the measure of the amount 00:16:16.753 --> 00:16:18.623 of a material that will dissolve 00:16:18.623 --> 00:16:19.763 in another material. 00:16:20.521 --> 00:16:23.181 For example, sugar is soluble in water, 00:16:24.153 --> 00:16:26.353 but ground black pepper is not. 00:16:27.925 --> 00:16:31.195 Try stirring sand into water, while you're 00:16:31.195 --> 00:16:33.225 stirring the sand mixes with the water 00:16:33.506 --> 00:16:35.116 but does not dissolve. 00:16:35.613 --> 00:16:37.813 When you stop stirring the sand falls 00:16:37.933 --> 00:16:39.283 to the bottom of the jar. 00:16:40.159 --> 00:16:42.979 The solubility of sand in water is zero. 00:16:43.682 --> 00:16:46.032 No amount of sand dissolves in water. 00:16:47.028 --> 00:16:49.328 Liquid solutions are usually transparent, 00:16:49.852 --> 00:16:52.172 they're evenly colored, and they can 00:16:52.172 --> 00:16:53.892 never separate into layers. 00:16:55.163 --> 00:16:57.503 Compare the mixture of oil and vinegar, 00:16:57.503 --> 00:17:00.003 as in salad dressing to a solution; like 00:17:00.003 --> 00:17:01.283 this drink mix. 00:17:02.489 --> 00:17:04.849 Also, solutions don't have to be liquid. 00:17:06.061 --> 00:17:07.821 They can be solids and gases too. 00:17:08.980 --> 00:17:10.760 In the sugar and water solution; 00:17:10.760 --> 00:17:13.420 a solid, sugar was mixed with a liquid, 00:17:13.420 --> 00:17:13.830 water. 00:17:15.314 --> 00:17:18.054 In a bottle of soda, the gas carbon dioxide 00:17:18.884 --> 00:17:21.184 is dissolved in or spread evenly 00:17:21.184 --> 00:17:22.374 throughout the liquid. 00:17:23.165 --> 00:17:24.975 When you lift the top off the bottle, 00:17:25.025 --> 00:17:26.735 you can see thousands of bubbles of 00:17:26.735 --> 00:17:29.085 carbon dioxide gas start to rise through 00:17:29.095 --> 00:17:30.735 the liquid an into the air. 00:17:31.997 --> 00:17:33.827 Mixtures of metals are solid solutions. 00:17:35.093 --> 00:17:37.453 Brass is a solution of zinc and copper. 00:17:38.797 --> 00:17:40.897 It is made by melting two metals 00:17:40.897 --> 00:17:41.327 together. 00:17:42.291 --> 00:17:43.791 Gases can form solutions too. 00:17:44.817 --> 00:17:46.767 Air is a solution of several gases. 00:17:47.947 --> 00:17:50.097 Physical changes can sometimes be easily 00:17:50.097 --> 00:17:52.217 reversed, but not always. 00:17:53.615 --> 00:17:56.105 Melting an ice cube can easily be reversed 00:17:56.105 --> 00:17:58.285 by cooling until it freezes again. 00:17:59.482 --> 00:18:01.702 Stirring sugar into water can be reversed 00:18:02.102 --> 00:18:04.062 by letting the water evaporate. 00:18:05.425 --> 00:18:07.795 On the other hand, it would not be 00:18:07.795 --> 00:18:10.645 so easy to get peanuts back once they 00:18:10.645 --> 00:18:12.095 were all ground up. 00:18:13.943 --> 00:18:15.933 Kyle: So if a change seems easy 00:18:15.933 --> 00:18:17.903 to reverse, it is more likely to be a 00:18:17.903 --> 00:18:18.453 physical change. 00:18:20.817 --> 00:18:22.747 Amanda: But not all combinations of 00:18:22.747 --> 00:18:24.917 matter can be separated physically into 00:18:24.917 --> 00:18:25.527 their parts. 00:18:27.135 --> 00:18:28.535 Mrs.Mcqule: Well done. 00:18:28.535 --> 00:18:30.275 Now for something really thrilling 00:18:30.425 --> 00:18:31.295 chemical changes. 00:18:32.978 --> 00:18:37.778 (background music) 00:18:38.988 --> 00:18:40.968 Mrs.Mcqule: Unlike the often "easy-to 00:18:40.968 --> 00:18:43.038 -reverse" physical changes, chemical 00:18:43.038 --> 00:18:45.718 changes don't turn around so easily. 00:18:46.228 --> 00:18:48.408 These changes occur when atoms link 00:18:48.408 --> 00:18:49.798 together in new ways. 00:18:50.875 --> 00:18:52.765 This is called a chemical reaction. 00:18:54.180 --> 00:18:56.450 During chemical reactions the atoms in 00:18:56.450 --> 00:18:58.300 the substances that were put together, 00:18:58.300 --> 00:19:01.190 rearranged to form a new substance with 00:19:01.190 --> 00:19:02.520 different properties. 00:19:02.520 --> 00:19:04.740 The changes in the linking patterns of the 00:19:04.740 --> 00:19:06.550 atoms create the new substances. 00:19:07.808 --> 00:19:09.948 These new substances have properties 00:19:09.948 --> 00:19:12.178 different from the original substances 00:19:12.178 --> 00:19:13.871 from which they were formed. 00:19:15.115 --> 00:19:16.875 Sugar is made when the right amounts 00:19:16.875 --> 00:19:19.715 of carbon, oxygen, and hydrogen atoms 00:19:19.715 --> 00:19:20.875 are mixed. 00:19:22.566 --> 00:19:24.546 A chemical reaction can cause sugar to 00:19:24.546 --> 00:19:26.356 break apart into it's original elements 00:19:27.065 --> 00:19:29.815 or atoms; carbon, oxygen and hydrogen. 00:19:31.388 --> 00:19:33.938 There are signals that a chemical change 00:19:33.938 --> 00:19:35.198 is happening. 00:19:35.198 --> 00:19:36.958 They include a formation of a gas, 00:19:36.958 --> 00:19:39.848 a color change, or light and heat changes 00:19:39.848 --> 00:19:41.178 caused by the release of energy. 00:19:42.660 --> 00:19:45.000 The reaction between baking soda and 00:19:45.000 --> 00:19:47.500 vinegar is an example of a chemical change. 00:19:49.039 --> 00:19:51.029 When these two materials are mixed gas 00:19:51.029 --> 00:19:52.279 bubbles form. 00:19:53.288 --> 00:19:55.248 A change in the linking pattern of the 00:19:55.248 --> 00:19:57.388 atoms in the liquid vinegar and solid 00:19:57.388 --> 00:19:59.598 baking soda, cause a new substance, 00:19:59.598 --> 00:20:02.518 carbon dioxide, a gas, to form. 00:20:03.862 --> 00:20:04.592 Kyle: Ahh. 00:20:04.592 --> 00:20:06.852 One of the signals, a gas was formed. 00:20:08.807 --> 00:20:10.587 Computer voice: With a burning candle, 00:20:10.587 --> 00:20:12.227 many changes are happening. 00:20:12.227 --> 00:20:15.247 Wax melts, runs down the side and turns 00:20:15.247 --> 00:20:17.957 solid again, this is a physical change. 00:20:19.121 --> 00:20:21.661 However, some of the wax turns into 00:20:21.661 --> 00:20:25.221 carbon dioxide gas and steam when it 00:20:25.221 --> 00:20:27.041 combines with oxygen in the air. 00:20:28.069 --> 00:20:30.949 This chemical change releases enough heat 00:20:30.979 --> 00:20:32.349 to make a flame. 00:20:33.262 --> 00:20:34.452 Amanda: A heat change! 00:20:35.507 --> 00:20:37.417 Computer voice: Rust forms when iron 00:20:37.417 --> 00:20:39.717 atoms in steel, react with oxygen from 00:20:39.717 --> 00:20:40.107 the air. 00:20:42.088 --> 00:20:44.368 The reaction is very complex and needs 00:20:44.368 --> 00:20:46.188 moisture to occur. 00:20:47.222 --> 00:20:49.452 When iron rusts it turns red or brown. 00:20:51.026 --> 00:20:52.146 Kyle: A color change. 00:20:52.521 --> 00:20:54.391 Mrs.Mcqule:Yes, but are you sure this 00:20:54.391 --> 00:20:56.681 is a chemical reaction? Or a physical 00:20:56.681 --> 00:20:57.261 change? 00:20:58.168 --> 00:20:59.158 Let's find out. 00:21:00.629 --> 00:21:03.179 Rust is powdery and no longer shiny 00:21:03.179 --> 00:21:06.629 like iron, it also does not bend like iron, 00:21:07.432 --> 00:21:13.482 iron can conduct electricity while rust 00:21:13.482 --> 00:21:17.692 does not, rust melts at a much higher 00:21:17.692 --> 00:21:21.692 temperature than iron, the density 00:21:21.692 --> 00:21:23.932 of rust is much less than the density 00:21:23.932 --> 00:21:27.252 of iron and rust does not react with 00:21:27.252 --> 00:21:28.742 oxygen as iron does. 00:21:30.333 --> 00:21:32.853 So is this a physical or chemical change? 00:21:33.295 --> 00:21:35.035 Both: Chemical change. 00:21:35.622 --> 00:21:37.692 Mrs.Mcqule: Right, we can see that a 00:21:37.692 --> 00:21:39.932 new substance is definitely been formed 00:21:39.932 --> 00:21:42.592 and a chemical reaction, has taken place. 00:21:43.139 --> 00:21:47.159 Now, rocketships use chemical reactions 00:21:47.159 --> 00:21:48.789 that produce lots of heat. 00:21:49.155 --> 00:21:54.855 (Rocket launches) 00:21:54.855 --> 00:21:58.425 (Astronaut talks) 00:21:58.425 --> 00:22:00.365 Mrs.Mcqule; This space shuttles main engines are 00:22:00.365 --> 00:22:02.185 powered by liquid hydrogen and liquid 00:22:02.185 --> 00:22:03.005 oxygen. 00:22:04.370 --> 00:22:06.420 When the oxygen and hydrogen come 00:22:06.420 --> 00:22:09.510 together, they make water vapor and 00:22:09.510 --> 00:22:11.300 release the energy the shuttle needs to 00:22:11.300 --> 00:22:12.140 take off. 00:22:13.512 --> 00:22:15.602 A chemical change has happened 00:22:15.602 --> 00:22:17.582 because the two substances hydrogen 00:22:17.582 --> 00:22:19.692 and oxygen came together to make a 00:22:19.692 --> 00:22:22.332 third new substance, water vapor. 00:22:23.262 --> 00:22:25.332 Burning is another chemical change. 00:22:26.295 --> 00:22:28.275 When wood burns, it turns into or 00:22:28.275 --> 00:22:29.985 becomes something else. 00:22:31.162 --> 00:22:34.947 It turns to smoke, heat and ash, it isn't 00:22:34.947 --> 00:22:36.268 wood anymore. 00:22:37.030 --> 00:22:39.260 That's because during burning, particles 00:22:39.260 --> 00:22:42.010 that make up the wood, react with oxygen 00:22:42.010 --> 00:22:43.700 in the air and change into other 00:22:43.700 --> 00:22:46.780 substances such as; carbon dioxide, ash 00:22:46.780 --> 00:22:48.020 and water vapor. 00:22:49.428 --> 00:22:51.988 Electricity can also cause chemical changes. 00:22:53.698 --> 00:22:55.748 If an electric current is sent through 00:22:55.748 --> 00:22:58.388 water, a different kind of change takes 00:22:58.388 --> 00:22:58.708 place. 00:22:59.783 --> 00:23:03.033 Gases are produced, but the gases are not 00:23:03.033 --> 00:23:06.573 water vapor, they are oxygen and hydrogen. 00:23:06.713 --> 00:23:09.013 The substances that make up water. 00:23:09.773 --> 00:23:12.353 When you eat food, chemical changes 00:23:12.353 --> 00:23:14.173 take place as you digest it. 00:23:15.554 --> 00:23:18.264 Digestion is a series of complex chemical 00:23:18.264 --> 00:23:20.354 changes, each consisting of many 00:23:20.354 --> 00:23:21.594 chemical reactions. 00:23:22.878 --> 00:23:24.818 When you ate breakfast, your teeth will 00:23:24.818 --> 00:23:26.948 make no physical change, breaking 00:23:26.948 --> 00:23:28.808 the food into smaller pieces 00:23:30.038 --> 00:23:32.238 and your saliva was chemically breaking 00:23:32.238 --> 00:23:35.058 down the food molecules into smaller 00:23:35.058 --> 00:23:37.128 and smaller particles. 00:23:38.159 --> 00:23:40.489 In your stomach acids reacted with the 00:23:40.489 --> 00:23:42.999 food to further change and make even 00:23:42.999 --> 00:23:44.389 smaller molecules. 00:23:45.667 --> 00:23:48.347 Finally, in the intestines, more digestive 00:23:48.347 --> 00:23:51.427 juices chemically reacted with what used 00:23:51.427 --> 00:23:53.627 to be oatmeal to produce the many 00:23:53.627 --> 00:23:56.307 different molecules of sugar, protein, and 00:23:56.307 --> 00:23:59.787 minerals your body uses to live and grow. 00:24:00.602 --> 00:24:03.182 All during digestion chemical reactions 00:24:03.182 --> 00:24:06.072 produce new substances with the atoms 00:24:06.072 --> 00:24:07.402 of the old substances. 00:24:09.320 --> 00:24:11.510 In general, chemical changes are difficult 00:24:11.510 --> 00:24:12.930 to reverse. 00:24:13.134 --> 00:24:14.804 (driver slams on brakes) 00:24:14.914 --> 00:24:17.544 Turning carbon dioxide gas, water, 00:24:18.050 --> 00:24:21.620 and sodium acetate back into baking soda 00:24:21.620 --> 00:24:23.920 and vinegar would be difficult. 00:24:25.200 --> 00:24:26.610 Kyle: And how about changing that 00:24:26.610 --> 00:24:28.520 oatmeal back into what my dad poured 00:24:28.520 --> 00:24:30.050 into my bowl this morning. 00:24:30.730 --> 00:24:32.950 Amanda: Imagine trying to "unburn" toast 00:24:32.950 --> 00:24:34.800 or "unspoil" milk. 00:24:35.770 --> 00:24:37.120 (bells ring) 00:24:37.706 --> 00:24:39.156 Mrs.Mcqule: We've seen and talked about 00:24:39.156 --> 00:24:41.486 physical and chemical changes in matter. 00:24:41.486 --> 00:24:43.486 But, sometimes it's hard to tell the 00:24:43.486 --> 00:24:44.146 difference. 00:24:45.449 --> 00:24:48.259 Physical changes are often easy to reverse 00:24:48.259 --> 00:24:51.639 but because matter can be changed in size 00:24:51.799 --> 00:24:55.569 and shape by being cut, folded, stretched 00:24:55.569 --> 00:24:58.329 ,rearranged and crumpled without 00:24:58.329 --> 00:25:00.659 changing its original properties 00:25:00.659 --> 00:25:03.319 it can look very different 00:25:03.481 --> 00:25:06.141 Matter can even be melted, frozen or 00:25:06.141 --> 00:25:07.951 heated to change its physical state. 00:25:08.697 --> 00:25:10.467 And although it looks different, it is 00:25:10.467 --> 00:25:11.777 still the same substance. 00:25:13.364 --> 00:25:14.974 Let's look at some examples. 00:25:16.254 --> 00:25:18.654 Cherry flavored drink powder is pale pink 00:25:19.001 --> 00:25:20.951 but turns bright red when you mix it 00:25:20.951 --> 00:25:23.881 with water, but the powder has only 00:25:23.881 --> 00:25:24.591 dissolved. 00:25:25.351 --> 00:25:26.831 It has gone through a physical change 00:25:27.194 --> 00:25:28.044 not a chemical change. 00:25:29.967 --> 00:25:31.587 Kyle: Oh, I would've thought that the 00:25:31.587 --> 00:25:33.587 color change, was a sign of a chemical 00:25:33.587 --> 00:25:33.937 change. 00:25:35.141 --> 00:25:36.871 Mrs.Mcqule: When you open a cold soft 00:25:36.871 --> 00:25:39.411 drink bubbles are produced but a chemical 00:25:39.411 --> 00:25:41.121 reaction is not taken place. 00:25:42.428 --> 00:25:44.618 The carbon dioxide has simply.. come 00:25:44.618 --> 00:25:45.248 out of solution. 00:25:47.187 --> 00:25:48.407 Amanda: Another sign of a chemical 00:25:48.407 --> 00:25:50.137 change that didn't plan out. 00:25:50.422 --> 00:25:52.042 Mrs.Mcqule: If you rub your hands quickly 00:25:52.042 --> 00:25:53.982 back and forth across the surface they 00:25:53.982 --> 00:25:56.062 become hot, but the heat is due to the 00:25:56.062 --> 00:25:58.312 friction, not a chemical reaction. 00:25:58.312 --> 00:26:00.182 Kyle: So a heat change sign doesn't 00:26:00.182 --> 00:26:01.202 always work either. 00:26:01.202 --> 00:26:02.472 Mrs.Mcqule: Cheer up Kyle. 00:26:02.472 --> 00:26:04.312 You know the basics about matter and 00:26:04.312 --> 00:26:05.592 if you know that.. you can figure out 00:26:05.592 --> 00:26:06.682 those tough spots. 00:26:07.919 --> 00:26:10.379 You now know the facts of matter. 00:26:10.735 --> 00:26:11.895 Kyle: I think I do. 00:26:12.135 --> 00:26:14.495 Mrs.Mcqule: So, tell us first what is 00:26:14.565 --> 00:26:15.305 matter. 00:26:16.988 --> 00:26:18.648 Kyle: Matter is anything that takes 00:26:18.648 --> 00:26:21.408 up space, has mass and has properties 00:26:21.408 --> 00:26:23.608 that you can observe and describe. 00:26:25.325 --> 00:26:26.535 Mrs.Mcqule: There are two kinds of 00:26:26.535 --> 00:26:28.795 properties, physical and chemical. 00:26:29.495 --> 00:26:30.655 How are they different? 00:26:31.861 --> 00:26:34.011 Kyle: Physical properties can be seen 00:26:34.011 --> 00:26:35.321 and measured without changing the 00:26:35.321 --> 00:26:37.201 matter into something else. 00:26:37.703 --> 00:26:39.483 Amanda: Chemical properties are harder 00:26:39.483 --> 00:26:41.403 to see because they describe the 00:26:41.403 --> 00:26:43.963 ability of matter to react with other matter 00:26:44.423 --> 00:26:46.483 to form some.. different matter. 00:26:47.682 --> 00:26:49.582 Mrs.Mcqule: What are the three physical 00:26:49.582 --> 00:26:52.292 properties that ALL matter has? 00:26:52.785 --> 00:26:55.055 Amanda: There are lots of physical 00:26:55.055 --> 00:26:56.895 properties, but three of them belong to 00:26:56.895 --> 00:26:59.815 all matter; mass (the amount of matter) 00:26:59.815 --> 00:27:02.685 that has volume (how much space it takes 00:27:02.685 --> 00:27:05.475 up) and density (mass compared to it's 00:27:05.475 --> 00:27:06.195 volume). 00:27:06.777 --> 00:27:08.907 Mrs.Mcqule: Hmm.. Do you know any other 00:27:08.907 --> 00:27:09.777 properties? 00:27:10.515 --> 00:27:11.585 Amanda: Sure. 00:27:11.585 --> 00:27:14.095 Most matter that is metallic is shiny, 00:27:14.095 --> 00:27:17.185 malleable, strong and a good 00:27:17.185 --> 00:27:20.665 conductor of heat, electricity and sound. 00:27:20.795 --> 00:27:23.185 Some metals like iron are magnetic. 00:27:23.683 --> 00:27:26.003 Most matter that is not metallic is 00:27:26.003 --> 00:27:30.003 not shiny, malleable, strong and is not a 00:27:30.003 --> 00:27:31.123 good conductor. 00:27:32.532 --> 00:27:34.962 Mrs.Mcqule: Now, what about changes? 00:27:35.072 --> 00:27:37.384 How can you tell a change is physical 00:27:37.444 --> 00:27:38.244 or chemical? 00:27:39.533 --> 00:27:41.293 Kyle: Physical changes don't make a 00:27:41.293 --> 00:27:43.533 new kind of matter, the matter keeps it's 00:27:43.533 --> 00:27:46.593 properties, when one kind of matter is 00:27:46.593 --> 00:27:48.543 physically mixed with another kind of 00:27:48.653 --> 00:27:51.193 matter.. it might look like something new 00:27:51.193 --> 00:27:53.923 but the parts can usually be separated. 00:27:54.899 --> 00:27:56.279 Amanda: But when there is a chemical 00:27:56.279 --> 00:27:59.219 change, the atoms in the matters that 00:27:59.219 --> 00:28:02.709 are mixed up together, hook up in new ways 00:28:02.709 --> 00:28:05.230 ;they change to form a new kind of matter. 00:28:06.551 --> 00:28:08.011 Kyle: Sometimes we can see the signs 00:28:08.011 --> 00:28:09.311 of a chemical change. 00:28:09.826 --> 00:28:12.626 There might be a color change, sometimes 00:28:12.626 --> 00:28:16.976 a gas forms, or energy can be released 00:28:16.976 --> 00:28:18.426 as light or heat. 00:28:19.538 --> 00:28:21.678 But.. you can't always count on those 00:28:21.678 --> 00:28:22.308 signals. 00:28:24.012 --> 00:28:26.032 Mrs.Mcqule: So, do you feel a little 00:28:26.032 --> 00:28:28.212 better on the properties of matter? 00:28:28.479 --> 00:28:29.889 And the changes that matter can go 00:28:29.889 --> 00:28:30.709 through? 00:28:30.709 --> 00:28:31.759 I know I do. 00:28:31.759 --> 00:28:33.629 Kyle: (Jokes around) as a MATTER of FACT 00:28:33.829 --> 00:28:34.329 I do. 00:28:35.766 --> 00:28:39.766 (background music) 00:28:44.882 --> 00:28:46.402 Kyle: Where's Mrs.Bailey? 00:28:46.834 --> 00:28:48.594 Woman: Oh, she's out today, I'm 00:28:48.594 --> 00:28:49.134 substituting. 00:28:49.880 --> 00:28:50.750 You're here early. 00:28:51.228 --> 00:28:53.258 Kyle: Yes I'm just.. excited about 00:28:53.258 --> 00:28:54.288 the test, I guess. 00:28:54.811 --> 00:28:57.391 Woman: Ahh the test.. physical and 00:28:57.391 --> 00:28:59.501 chemical changes in matter. 00:29:00.085 --> 00:29:02.865 Kyle: Yeah.. I hope I do ok.. (gasps) 00:29:04.244 --> 00:29:05.944 Mrs.Mcqule: I think you'll do fine. 00:29:05.944 --> 00:29:06.414 Just fine. 00:29:08.647 --> 00:29:09.587 (♫ Sings ♫) NOTE Paragraph 00:29:09.587 --> 00:29:12.367 Both: M is for metric, conversion to a cup 00:29:12.367 --> 00:29:14.497 A is for astronaut cause they go to the 00:29:14.497 --> 00:29:14.927 moon. 00:29:16.181 --> 00:29:18.241 T is for tattertot cause they are really 00:29:18.241 --> 00:29:18.591 good. 00:29:18.967 --> 00:29:20.757 T is for toddlers cause they go "room 00:29:20.757 --> 00:29:22.397 room room". 00:29:22.738 --> 00:29:24.608 E is for elephant cause they take up 00:29:24.608 --> 00:29:25.198 much space. 00:29:25.994 --> 00:29:28.634 R is for radical cause matter's really cool 00:29:29.317 --> 00:29:33.067 M-a-t-t-e-r (shouts) Matter!! 00:29:38.704 --> 00:29:40.334 Amanda: For more great videos call