Someone might claim that air is not matter because you can’t see it. Write a paragraph showing how you would prove to this person that air is matter.

Will an object with a higher density displace more water than an object with a lower density? Explain why or why not.

Explain how you can remove a metal coating from an object.

What generalization can you make about a substance that is soluble in water and conducts electricity once it has dissolved? Explain your thinking.

How is the arrangement of electrons in an atom related to the location of the atom on the periodic table?

How many elements are included in the chemical formula for sodium nitrate, $NaNO_3$? Name them.

Look again at the copper-cycle diagram. After adding zinc, the blue solution turns colorless, and copper appears as a solid. What do you think happened to the zinc? Explain your thinking.

Write the nuclear equation for the beta decay of cerium-141.

How are potassium-39, potassium- 40 , and potassium- 41 different from each other? Write the isotope symbols for the three isotopes of potassium.

Which of the following compounds will generally not form?

(A) $\mathrm{KBr}$

(B) $\mathrm{NeBr}_2$

(C) $\mathrm{AlBr}_3$

(D) All of these compounds will form.

The acetate ion $\mathrm{C}_2 \mathrm{H}_3 \mathrm{O}_2{ }^{-}$ has a charge of $-1$. What is the correct formula for calcium acetate?

(A) $\mathrm{CaC}_2 \mathrm{H}_3 \mathrm{O}_2$

(B) $\mathrm{Ca}_2 \mathrm{C}_2 \mathrm{H}_3 \mathrm{O}_2$

(C) $\mathrm{Ca}\left(\mathrm{C}_2 \mathrm{H}_3 \mathrm{O}_2\right)_2$

(D) $\mathrm{C}_2 \mathrm{H}_3 \mathrm{O}_2 \mathrm{Ca}$

How does the rule of zero charge help you predict the formula of an ionic compound?

Describe a way to determine whether a substance conducts electricity.

Name the four models of bonding and explain them in your own words. Be specific about the location of the valence electrons.