Question

unit 1 lesson 3 vocabulary
circle the term that best completes the sentence.

1. a chemist wanted to identify an unknown ( dissolve, substance), so she measured its melting point and density. these observable characteristics are known as its physical (property, mixture).
2. when you add sugar to water, the sugar will (dissolve, soluble), forming a transparent liquid. this combination is a type of (substance, mixture).
3. salt is (soluble, insoluble) in water because the water.
4. on the other hand, sand is (insoluble, soluble) in water, meaning it will not break apart and mix uniformly with the water.
5. after observing that the sand did not (dissolve, property) in the water, the student concluded that the combination of sand and water was a (mixture, solution) where the separate substances are still visible.

Explanation:

1. A chemist identifies an unknown substance by its physical properties like melting - point and density.
2. Sugar dissolves in water to form a mixture.
3. Salt is soluble in water.
4. Sand is insoluble in water.
5. Since sand doesn't dissolve in water, the combination is a mixture.

Answer:

1. substance, property
2. dissolve, mixture
3. soluble
4. insoluble
5. dissolve, mixture