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3 years ago

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Given the equation Ca + H2O --> Ca(OH)2 + H2 how many grams of calcium will react completely with 10.0 grams of water? *

1 answer:

Yuki888 [10]3 years ago

3 0

Answer: 11.0 g of calcium will react with 10.0 grams of water.

Explanation:

To calculate the moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}$

moles of $H_2O$

$\text{Number of moles}=\frac{10.0g}{18g/mol}=0.55moles$

The balanced chemical equation is:

$Ca+2H_2O\rightarrow Ca(OH)_2+H_2$

According to stoichiometry :

2 moles of $H_2O$ require = 1 mole of $Ca$

Thus 0.55 moles of $H_2O$ require= $\frac{1}{2}\times 0.55=0.275moles$ of $Ca$

Mass of $Ca=moles\times {\text {Molar mass}}=0.275moles\times 40g/mol=11g$

Thus 11.0 g of calcium will react with 10.0 grams of water.

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Purification of copper can be achieved by electrorefining copper from an impure copper anode onto a pure copper cathode in an el

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According to mole concept:

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To calculate the time required, we use the equation:

$I=\frac{q}{t}$

where,

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t = time required = ?

Putting values in above equation, we get:

$40.0=\frac{42551181 C}{t}\\\\t=1063779sec$

Converting this into hours, we use the conversion factor:

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3 years ago

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Explanation:

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