For each reaction, write the chemical formulae of the oxidized reactants in the space provided. Write the chemical formulae of the reduced reactants in the space provided.

Explanation:

First Reaction;

Ca + ZnCl2 --> CaCl2 + Zn

Oxidized Reactant: Ca. There is increase in oxidation number from 0 to +2

Reduced Reactant: Zn. There is decrease in  oxidation number form +2 to 0

Second Reaction:

FeI2 + Mg --> Fe + MgI2

Oxidized Reactant: Mg. There is increase in oxidation number from 0 to +2

Reduced Reactant: Fe. There is decrease in  oxidation number form +2 to 0

Third Reaction;

Mg + 2AgNO3 --> Mg(NO3)2 + Ag

Oxidized Reactant: Mg. There is increase in oxidation number from 0 to +2

Reduced Reactant: Ag. There is decrease in  oxidation number form +1 to 0

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e