I already have the first two answers I'm just stuck with the last two. A student demonstrates the reaction by mixing 25.00 g of H2SO4 with 25.00 g of CaCO3. a. How many moles of each reactant does the student mix? 2.55 x 10^-1 mol H2SO4 Approx. 2.5 x 10^-1 mol CaCO3 b. Identify the limiting reactant. Explain how you know this. CaCO3 c. Calculate the theoretical mass of the excess reactant. d. Soon after mixing the reactants, the student determines that 33.17 g of CaSO4 was produced by the reaction. Is this a reasonable result? Show calculations to defend your answer.

1. b

2. c

3. a

Explanation: A chemical reaction in equilibrium is actually in a dynamic euqilibrium, which means that changing a condition will make the equilibrium move to counteract the action and reestate the equilibrium.

For example, in the reaction:

N2(g) + 3H2(g) ⇄ 2NH3(g)

1. Adding H2: if you add the reagent, to reestate the equilibrium, the reaction will produce more products so, it will move to the right;

2. A catalyst doesn't interfere in the equilibrium, because it moves to the right and to the left at the same extent. Therefore, there is no effect.

3. Decrease the pressure: when you decrease the pressure of a reaction, the equilibrium will make the pressure increase again by moving towards the side of the reaction which has more molecules, so, it shifts to the left;