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3 years ago

HELP!!!

Chemistry

1 answer:

Helen [10]3 years ago

3 0

Answer:

The answer to your question is 8.1 g of ZnCl₂

Explanation:

Data

mass of ZnCl₂ = ?

mass of Zn = 7.0 g

mass of CuCl₂ = 8 g

Balanced chemical reaction

Zn + CuCl₂ ⇒ ZnCl₂ + Cu

Process

1.- Calculate the molar mass of the reactants

Zn = 65.4 g

CuCl₂ = 63.6 + (35.5 x 2) = 134.6 g

2.- Calculate the limiting reactant

theoretical yield CuCl₂ / Zn = 134.6/65.4 = 2.06

experimental yield CuCl₂ / Zn = 8/7 = 1.1

The limiting reactant is CuCl₂ because the experimental yield was lower than the theoretical yield.

3.- Use proportions to calculate the mass of ZnCl₂

molar mass of ZnCl₂ = 65.4 + (35.5 x 2) = 136.4 g

134.6 g of CuCl₂ ---------------- 136.4 g of ZnCl₂

8 g ---------------- x

x = (8 x 136.4) / 134.6

x = 8.1 g of ZnCl₂

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