Chemical Reactions

The substances that undergo change in a chemical reaction are called

• reactants.

• products.

• coefficients.

• elements.

Which of the following does NOT state what the arrow means in a chemical equation?

• forms

• produces

• conserves

• yields

Which of the following is a balanced chemical equation for the synthesis of NaBr from Na and Br?

• A

• B

• C

• D

Which of the following is NOT always true about a synthesis reaction?

• One product is formed.

• There is only one reactant.

• The general formula is A + B → C.

• A reactant might be a compound, or it might be an element.

Aluminum and copper (II) chloride react to form copper and aluminum chloride. Which list correctly identifies the reactants and products of this reaction?

• Al, CuCI2, Cu, and AICI3 are all ionic solids

• Al and Cu are metals, CuCI2, and AICI3 are ionic solids

• AI and CuCl2 are ions, Cu and AICl3 are ionic solids

• Al and Cu are ions, CuCl2 and AlCl3 are metals

In aqueous solution, sodium chloride (NaCl) shows that it is made of sodium ions (Na+) and chloride ions (Cl-). Which statement explains the formation of ions when sodium chloride is formed from sodium and chlorine?

• The sodium atoms each lose an electron and the chlorine atoms each gain an electron.

• The sodium atoms each gain an electron and the chlorine atoms each lose an electron.

• Both the sodium atoms and the chlorine atoms gain one electron each.

• Both the sodium atoms and the chlorine atoms lose one electron each.

Calcium fluoride (CaF2) is an ionic solid that is a natural source of fluorine for the chemical industry. What is the charge on the calcium ion in calcium fluoride?

• -2

• -1

• +1

• +2

DeWayne has these Australian coins in his collection. The penny is composed of pure lead, and the shilling is composed of sterling silver, an alloy of silver and copper. Which statement correctly identifies the type of matter for both coins?

• Both coins are compounds because they are both made of metal.

• Both coins are mixtures because they are both made of metal.

• The penny is made of an element because it is pure lead, and the shilling is a compound because it is made of more than one metal.

• The penny is made of an element because it is pure lead, and the shilling is a mixture because it is an alloy.

Which element, represented by X, would have the valence electron configuration shown in the diagram?

• lithium (Li)

• boron (B)

• sodium (Na)

• phosphorus (P)

All of these atoms lend electrons and form positive ions EXCEPT

• A

• B

• C

• D