Embibe Experts Solutions for Chapter: Chemical Calculations, Exercise 1: West Bengal Board-2020

If the vapour density of the carbon containing gaseous substance is $13$, which of the following is its molecular formula?

${\mathrm{SO}}_2$ required for industrial production of sulphuric acid is produced by burning iron pyrites in excess air current. The chemical equation of the current is given below:

How many grams of ${\mathrm{FeS}}_2$ is required for the production of $512\mathrm{g}$ of ${\mathrm{SO}}_2$? $\left[\mathrm{Fe}=56, \mathrm{S}=32, \mathrm{O}=16\right]$

By heating $200 \mathrm{g}$ of metal carbonate, $112 \mathrm{g}$ of metal oxide on a gaseous compound are produced. Vapour density of the gaseous compound is $22$. How many moles of gaseous compound is produced in the reaction?

How many grams of $\mathrm{Al}$ are required to prepare $558 \mathrm{g}$ of $\mathrm{Fe}$ by the reduction of ${\mathrm{Fe}}_2{\mathrm{O}}_3$, with $\mathrm{Al}$ at high temperature? How many moles of ${\mathrm{Fe}}_2{\mathrm{O}}_3$ will be required in the reaction? $(\mathrm{Fe}=55.8, \mathrm{Al}=27, \mathrm{O}=16)$

By heating $32.1 \mathrm{g}$ ammonium chloride with calcium hydroxide $10.2 \mathrm{g} {\mathrm{NH}}_3$ , $33.3 \mathrm{g} {\mathrm{CaCl}}_3$  and $10.8 \mathrm{g} {\mathrm{H}}_2\mathrm{O}$ are obtained. How many grams of calcium hydroxide take part in the reaction? How many moles of ${\mathrm{NH}}_3$ and how many litres of ${\mathrm{NH}}_3$, at STP is formed at the reaction? 

According to the following chemical equation,

${\mathrm{CH}}_4+2{\mathrm{O}}_2\to {\mathrm{CO}}_2+2{\mathrm{H}}_2\mathrm{O}$

what volume of ${\mathrm{O}}_2$ will be required to burn $10$ mole of ${\mathrm{CH}}_4$ at STP?

A and B react to produce C according to the following chemical equation 
$2\mathrm{A} + \mathrm{B} \to 2\mathrm{C}$

A, B and C are the formulas for three gaseous substances. The vapour densities of A and B are 32 and 16 respectively. Find out the vapour density of C. 

According to the following chemical equation:

$2\mathrm{ZnS} + 3{\mathrm{O}}_2 \to 2\mathrm{ZnO} + 2 {\mathrm{SO}}_2$

from 100 mole of $\mathrm{ZnS}$

(i) how many gram of $\mathrm{ZnO}$, and

(ii) how many mole of ${\mathrm{SO}}_2$, will be produced ? 
($\mathrm{Zn}=65.5, \mathrm{S} = 32, 0 = 16$)