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Does anyone know the answer to these?

Does anyone know the answer to these?-example-1
User AlexOwl
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1 Answer

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Answer:

The answer to your question is below

Step-by-step explanation:

Data

mass of CaCO₃ = 155 g

mass of HCl = 250 g

mass of CaCl₂ = 142 g

reactants = CaCO₃ + HCl

products = CaCl₂ + CO₂ + H₂O

1.- Balanced chemical reaction

CaCO₃ + 2HCl ⇒ CaCl₂ + CO₂ + H₂O

2.- Limiting reactant

molar mass of CaCO₃ = 40 + 12 + 48 = 100 g

molar mass of HCl = 2[1 + 35.5 ] = 73 g

theoretical proportion CaCO₃ /HCl = 100 / 73 = 1.37

experimental proportion CaCO₃ /HCl = 155 / 250 = 0.62

As the experimental proportion was lower than the theoretical proportion the limiting reactant is CaCO₃

3.-

Calculate the molar mass of CaCl₂

CaCl₂ = 40 + 71 = 111 g

100 g of CaCO₃ ------------------ 111 g of CaCl₂

155 g of CaCO₃ ----------------- x

x = (155 x 111) / 100

x = 17205 / 100

x = 172.05 g of CaCl₂

4.- percent yield

Percent yield = 142 / 172.05 x 100 = 82.5 %

5.- Excess reactant

100 g of CaCO₃ -------------------- 73 g of HCl

155 g of caCO₃ ------------------- x

x = (155 x 73)/100

x = 133.15 g

Mass of HCl = 250 - 133.15

= 136.9 g

User Adrian Toman
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