Question

A 0.005 mol sample of anhydrous calcium carbonate was completely thermally decomposed to give 100 cm3 of gas measured at a certain temperature and pressure.
In a separate experiment carried out at the same temperature and pressure, a 0.005 mol sample of anhydrous calcium nitrate was completely thermally decomposed. The volume of gaseous products was measured.
What total volume of gaseous products was produced from the calcium nitrate?

Answer 1

Answer: 250cm^3

Explanation:

Ca(NO3)2→ CaO + 2NO2 + 1/2O2

1                              (2+1/2)=2.5

1 : 2.5(NO2+O2)

1 mol→100cm^3

2.5mol→(2.5×100)=250cm^3

Answer 2

Answer:

The volume of the gaseous products was produced from the thermal decomposition of calcium nitrate is equal to 250cm³.

Explanation:

The balanced chemical reaction of the thermal decomposition of calcium carbonate:

$CaCO_{3}\; \longrightarrow CaO(s)\; \; +\; \; CO_{2}\;(g)$

1mole of  calcium carbonate produced = 1mole carbon dioxide

0.005mol of CaCO₃ produced $=0.005mol$ CO₂

Given, the volume of gaseous products i.e. CO₂ = 100cm³

Thermal decomposition of calcium nitrate:

$Ca(NO_{3})_{2}\; \; {\longrightarrow}\; CaO(s)\; \; + 2NO_{2}(g)\; \; + \; \; \frac{1}{2} O_{2}(g)$

1 mole of calcium nitrate gives gaseous products $=\frac{1}{2} +2=2.5mol$

0.005mol of  calcium nitrate will give gaseous products $= 0.005*2.5$

                                                                                             $=0.0125mol$

Now the volume of 0.005mol of gaseous products $= 100cm^{3}$

The volume of 0.0125mol of gaseous products $= 100*(\frac{0.0125}{0.005} )=250cm^{3}$

Therefore, the volume of gaseous products formed on the decomposition of calcium nitrate is 250cm³.