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Why do the properties of a pure substance do not vary from sample to sample?
Explain why the properties of a pure substance do not vary from sample to sample. The properties of a pure substance are constant because its composition is always the same. It can’t be broken down into simpler substances. A compound can be broken down into simpler substances, but an element cannot.
Which state of matter has a definite volume but a variable shape?
liquid
Matter in the solid state maintains a fixed volume and shape, with component particles (atoms, molecules or ions) close together and fixed into place. Matter in the liquid state maintains a fixed volume, but has a variable shape that adapts to fit its container.
When Italian salad dressing is left standing it separates into layers the salad dressing is a N?
8 – CHEMICAL AND PHYSICAL CHANGES FLASHCARDS
| A | B |
|---|---|
| ITALIAN DRESSING WILL SEPARATE INTO LAYERS OF OIL AND VINEGAR UPON STANDING | PHYSICAL CHANGE |
| Water decomposes into H2 and O2 by electrolysis. | CHEMICAL CHANGE |
| Tiny droplets of water condense as dew on grass. | PHYSICAL CHANGE |
| Marble statues are defaced by acid rain. | CHEMICAL CHANGE |
What are two physical properties that can vary even when the substance with these properties does not change?
Intensive properties, such as density and color, do not depend on the amount of matter. Both extensive and intensive properties are physical properties, which means they can be measured without changing the substance’s chemical identity.
What has a variable shape but a definite volume?
A solid has definite volume and shape, a liquid has a definite volume but no definite shape, and a gas has neither a definite volume nor shape.
What causes salad dressing to separate?
No matter how hard you try to shake, stir, or whisk oil and vinegar together, they eventually separate. This happens because vinegar and oil are made of very different types of molecules that are attracted to their own kind. Oils are a type of fat (like butter, shortening, and lard) and are considered non-polar.
Is salad dressing separating a chemical change?
Salad dressing (such as oil and vinegar dressing) separating into layers after standing is an example of a chemical change because the end result looks different from how it started.
Why does oil and vinegar separate into layers chemistry?
Oil and vinegar separate into layers because it is a suspension which is a mixture in which particles settle in separate into layers overtime. Oil and vinegar will not dissolve as vinegar has a higher density compared soil which will float.