Matter Review

How are the properties of helium (He) and krypton (Kr) similar?

• Both are nonreactive gases at room temp.

• Both are nonreactive liquids at room temp.

• Both are reactive gases at room temp.

• Both are reactive liquids at room temp.

A scientist experiments on a piece of solid copper.

The scientist heats the copper and observes the copper's density decreases as its temperature increases. The scientist continues to heat the copper until it melts. How are the decrease in density and the melting similar?

• They are both physical changes, because the composition of the copper piece remains the same.

• They are both chemical changes, because the composition of the copper piece remains the same.

• They are both physical changes, because the new substance has different chemical properties than copper.

• They are both chemical, because the new substance has different chemical properties than copper.

A student pours a cloudy liquid through a thin piece of paper. The student observes the collected liquid is not cloudy. How should the student classify the original cloudy liquid?

• A mixture, because the cloudy liquid was separated by evaporation

• A mixture, because the cloudy liquid was separated by filtration.

• A compound, because the cloudy liquid was separated by evaporation.

• A compound because the cloudy liquid was separated by filtration.

Wendy draws a model of the neutral element beryllium (Be). Wendy's teacher says there is an error in her model. What is the error?

• The model has too many protons, electrons and neutrons

• The model doesn't have enough protons

• The model has 2 less electrons

Terry is learning about chemical reactions. Terry's teacher draws this equation on the board. Terry claims the equation shows the Law of Conservation of Mass. What evidence supports her claim.

4Al + 3O₂ → 2 Al₂ O₃

• She is ending up with a new substance.

• It doesn't because the equation is not balanced.

• She's showing the same amount of reactants and products.

The periods on the periodic chart shows the number of valence electrons the element has.

• True

• False

How many neutrons does Titanium have?

• 28

• 22

• 26

• 21

In which group are the noble gases located?

• 13

• 1

• 6

• 18

A mixture in which the substances are evenly distribute, and you can not see the different parts is a _________ mixture.

• Homogeneous

• Heterogeneous

What is water?

• An element

• A mixture

• A compound