Give four examples illustrating each of the following terms. a. homogeneous mixture d. element b

step 1 So this question is pretty straightforward. It's just asking you to make a list of various thing

Give four examples illustrating each of the following terms....

Key Concepts

Chemical Change

A chemical change occurs when a substance undergoes a transformation that results in the formation of one or more new substances with different chemical identities. This involves the breaking and forming of chemical bonds, and is fundamental in the study of chemical reactions, synthesis, and decomposition processes.

Element

An element is a fundamental substance that is made up of only one type of atom and cannot be broken down into a simpler substance by chemical means. Elements serve as the building blocks of all matter, playing a central role in the periodic table and chemical nomenclature.

Physical Change

A physical change involves a change in the form or state of a substance without altering its chemical composition. It includes changes such as melting, freezing, or chopping, where the material's identity remains the same, which is essential for understanding phase transitions and reversible processes in chemistry.

Heterogeneous Mixture

A heterogeneous mixture consists of distinguishable, separate components that are not uniformly distributed, making it possible to visually identify the different substances present. This concept is important in understanding separation techniques and the nature of mixtures in both everyday life and laboratory settings.

Compound

A compound is a chemical substance that forms when two or more elements are chemically bonded together in a fixed ratio, resulting in properties that are distinct from the individual elements. This concept underpins the study of chemical reactions and molecular structure in chemistry.

Homogeneous Mixture

A homogeneous mixture is one in which the constituent components are uniformly distributed throughout the mixture, meaning that no matter where you sample from the mixture, its composition remains constant. This concept is crucial for understanding procedures in which complete blending or solvation is required, such as creating a solution in chemistry.

Transcript

00:01 So this question is pretty straightforward.

00:02 It's just asking you to make a list of various things, right? so homogeneous solutions, heterogeneous solutions, physical and chemical changes, and et cetera.

00:14 Right.

00:14 So we're going to start with homogeneas solutions.

00:16 So there's really an infinite number of answers.

00:18 Right.

00:19 So a homogeneous, i think it's really asking about homogeneous mixtures.

00:25 And i wrote solutions because a homogeneous mixture is.

00:30 A solution and that was an accident i promise right so homogeneous mixtures are solutions so you pick any solution that you know is a solution and that's going to be a homogeneous mixture right so i'll just give you one example right so salt and water so let's say you're making pasta and you're boiling some water once you start adding salt and get that stirred that salt is going to evenly disperse itself into the water air is a homogeneous mixture, right? so air is composed of several gases, mostly nitrogen and oxygen, but those gas molecules or those gas, yeah, those gas molecules are evenly spread out throughout the entire atmosphere of the planet.

01:18 So that's considered a homogeneous mixture.

01:22 Gasoline is a homogeneous mixture, right? it's composed of carbon and hydrogen -based large linear molecules.

01:31 So that's a homogeneous mixture and vinegar.

01:35 Vinegar is mostly a solution of acetic acid, and you'll become familiar with what acetic acid is.

01:42 That's not how you spill vinegar, matt.

01:44 Good job.

01:47 But you'll become familiar with acetic acid in a few chapters when you start learning about acid and bases.

01:54 But they're all homogeneous mixtures because they're solutions.

01:57 Heterogeneous solutions is not a thing.

02:00 I meant to write mixtures, right? so you can't have a heterogeneous solution because a solution implies homogeneity.

02:08 Heterogeneous mixtures are when you have the components of your mixture are not evenly dispersed.

02:14 So an example of that would be if you put ice in your drink, right? so let's say you're drinking soda and you add some ice cubes.

02:22 Those ice cubes aren't going to be evenly dispersed throughout the soda.

02:26 I'll say ice in drink.

02:29 The ice cubes are going to stay on the top.

02:31 So that's the components of your liquid and your ice are not evenly dispersed throughout the volume of the glass that you're drinking out of.

02:40 So that's considered heterogeneous.

02:43 Cereal and milk for the same reason, right? your cereal pretty much floats to the top.

02:48 Let's see you're having some cheerios.

02:51 The cheerios aren't going to be evenly dispersed throughout all the milk.

02:55 Sand and water.

02:56 If you try to dissolve sand and water, it's not going to work.

02:59 Your sand is just going to stay at the bottom of your glass.

03:01 The sand is not evenly distributed out throughout the water.

03:06 And a chocolate chip cookie, because it's very difficult to get the chocolate chips evenly distributed throughout the entire cookie.

03:15 You really have these localized pockets of chocolate, right? so if you make a chocolate chip cookie, you'll notice that the white part is mostly the cookie and your chocolate chips are not evenly dispersed throughout the.

03:33 The cookie.

03:33 I might have drawn it that way, but in most cookies, that's not the case.

03:38 Compounds are composed of two or more elements.

03:46 So there's, again, an infinite number of examples of compounds.

03:51 I'm going to list some that you might actually be familiar with.

03:54 So, for example, salt, which is sodium chloride, nacl, is a compound.

04:01 You have one atom of sodium and one atom of chlorine.

04:06 Glucose, sugar is c6h12 .06.

04:14 Rust, so rusted metal is what's called iron oxide.

04:21 So it's two atoms of iron and three atoms of oxygen.

04:24 This is rust.

04:26 I thought that would be pretty neat to show you.