Question 1 A hypothesis is a plausible explanation for a particular fact, observation, or process. Write a hypothesis

about how the various concentrations of acid will affect the amount of limestone that is dissolved from

each jar.

Hypothesis:

The amount of limestone that dissolves in the acid is directly proportional to the concentration of acid used.

Explanation:

Acids dissolve limestone according to the following general equation;

2HX(aq) + CaCO3(s) > CaX2(aq) + H2O (l) + CO2(g). Where HX represents any acid at all.

This dissolution process is a chemical reaction. It was experimentally observed that the amount of limestone that dissolved in acid depends on the concentration of acid. Various concentrations of acid were then prepared and a particular mass of limestone was dissolved in each concentration of acid. The amount of limestone dissolved in each case was carefully noted.

It was observed that as the concentration of acid increased, the amount of limestone dissolved increased also and vice versa, hence the hypothesis proposed above.

the current is 0.6

voltage ÷ resistance = current

so 12 ÷ 20 = 0.6