Question

Use the periodic table to answer this question. Decomposing calcium carbonate yields calcium oxide and carbon dioxide. What information is needed to calculate the mass of calcium oxide that can be produced from 4.7 kg of calcium carbonate?

Answer 1

Answer : The mass of calcium oxide produced is, 2632 g

Solution : Given,

Mass of calcium carbonate = 4.7 Kg = 4700 g      (1 Kg = 1000 g)

Molar mass of calcium carbonate = 100 g/mole

Molar mass of calcium oxide = 56 g/mole

First we have to calculate the moles of calcium carbonate.

$\text{Moles of }CaCO_3=\frac{\text{Mass of }CaCO_3}{\text{Molar mass of }CaCO_3}=\frac{4700g}{100g/mole}=47moles$

Now we have to calculate the moles of calcium oxide.

The balanced decomposition reaction will be,

$CaCO_3\rightarrow CaO+CO_2$

From the balanced reaction we conclude that,

As, 1 mole of calcium carbonate decompose to give 1 mole of calcium oxide

So, 47 moles of calcium carbonate decompose to give 47 moles of calcium oxide

Now we have to calculate the mass of calcium oxide.

$\text{Mass of }CaO=\text{Moles of }CaO\times \text{Molar mass of }CaO$

$\text{Mass of }CaO=(47moles)\times (56g/mole)=2632g$

Therefore, the mass of calcium oxide produced is, 2632 g

Answer 2

This may help you

First write and balance the equation, being: CaCO3 - CaO + CO2 Then, using the periodic table, find the molecular masses of CaCO3 and of CaO, finding their ratio. That will be 100g:56g or 0.1kg:0.056kg. Since you have 4.7kg of CaCO3, it corresponds to Xkg of CaO. Making x the subject, it should be X= 4.7*0.056/100=0,002632