Classify each change as physical or chemical. a. Sugar burns when heated in a skillet. b. Sugar dissolves in water. c. A platinum ring becomes dull because of continued abrasion. d. A silver surface becomes tarnished after exposure to air for a long period of time.

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Alright. So here we need to identify whether the following is a physical or a chemical change. Alright, so remember a physical change is going to be something that um that you do, that does not change the chemical composition, so does not change the chemical composition of that substance. So whatever the change that you do to that matter, it's still the same matter, it's still the same element, it's still the same compound. Chemical change. There is change. So you do change, do change the chemical composition of that substance. Alright, so resting, iron bar, resting is the form of a chemical reaction. It's a chemical change, its oxidation. So this is going to be chemical alright, melting a bar of butter so by melting the butter, as long as you're not, you know, burning it or boiling it, um just melting it, you're just taking butter in a solid state and you are turning it into more of the liquids to so you're just changing the phase of the butter, but it's still butter. Nothing chemical reaction has not taken place. So this is just going to be a physical change, Okay, dissolving sugar and water. So whenever sugar dissolves in water, it's still um the molecules are staying staying together, they don't actually dissociated into, you know, different ions or anything. Um So this is actually a physical change, right? It's just a physical change because you can actually evaporate the water from that solution and you're going to get the sugar crystals back out of it. So it's not actually breaking up the sugar molecules, they're staying intact, they're just dissolving in the water, burning a log of wood. So anytime you're burning combusting cooking something that is an example of a chemical change, you can't simply unburned wood, you can't simply uncooked food. Um It's kind of a you know, most of them are permanent changes because you've taken a substance and you've change the chemical composition of it. You perform a chemical reaction on it, tearing a piece of paper. So even though tearing a piece of paper you can't really untether it. Um It's still going to be paper that they end, right? So it's just a physical it's a physical change. It's still paper. It's not changing the composition of that paper, it's still the same molecules. They're just um you know, you just cut them or tear them apart but it's still the same thing. All right. Thanks so much for watching. We'll see you in the next video

Classify each change as physical or chemical. a. Sugar burns when heated in a skillet. b. Sugar dissolves in water. c. A platinum ring becomes dull because of continued abrasion. d. A silver surface becomes tarnished after exposure to air for a long period of time.

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