During an experiment, 102 grams of calcium carbonate react with an excess amount of hydrochloric acid. if the percent yield of the reaction was 85.15%, what was the amount of calcium chloride formed?

96.31 g.

Explanation:

CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O,

1.0 mole of CaCO₃ reacts with 2.0 moles of HCl to produce 1.0 mole of CaCl₂, 1.0 mole of CO₂, and 1.0 mole of H₂O.

no. of moles of CaCO₃ = mass/molar mass = (102 g)/(100.08 g/mol) = 1.019 mol.

Using cross multiplication:

1.0 mole of CaCO₃ produce → 1.0 mole of CaCl₂.

∴ 1.019 mole of CaCO₃ produce → 1.019 mole of CaCl₂.

∴ The amount of CaCl₂ produced = no. of moles x molar mass = (1.019 mol)(110.98 g/mol) = 113.1 g.

∵ percent yield of the reaction = [(actual yield)/(theoretical yield)] x 100.

Percent yield of the reaction = 85.15%, theoretical yield = 113.1 g.

∴ actual yield = [(percent yield of the reaction)(theoretical yield)]/100 = [(85.15%)(113.1 g)] / 100 = 96.31 g.

answer: - 3.) the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

solution: - as per the rules, oxidation number of oxygen in its compounds is -2. the sum of oxidation numbers of all the elements of a molecule or compound is zero.

also, the oxidation number in elemental form is zero.

in no, the oxidation number of o is -2 so the oxidation number of n is +2 so that the sum is zero.

similarly, the oxidation number of c in co is +2 and o is -2.

on product side the oxidation number of n is 0 as it is in the elemental form() .

oxidation number of c in carbon dioxide is +4 as there are two oxygen in it and we know that each oxygen is -2.

so, oxidation number of n is changing from +2 to 0 and the oxidation number of c is changing from +2 to +4.

since nitrogen is reduced and hence no is acting as an oxidizing agent. carbon is oxidized and so co is acting as a reducing agent.

so, the right choice is number 3.)the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.