Stoichiometry, Short Questions, Chemistry 11 … msa

Short Questions on Stoichiometry

This page consists of solutions of short questions included in the Stoichiometry course of First Year.

Question No

Statement of the question

Question 1

What is gram atom? Why the concept of gram atom is useful in chemistry? See Answer

Question 2

The mass of 5 moles of an element X is 60 g. Calculate the molar mass of this element. Name the element.

Question 3

Explain why balanced chemical equations are used in stoichiometric problems?

Question 4

How will you identify the limiting reagent in a reaction?

Question 5

Define molar volume of a gas. What will be the volume of 2.5 moles of H₂ gas and 60 g NH₃ at STP?

Question 6

Why the actual yield is usually less than the theoretical yield of a reaction?

Question 7

(a) What do you mean by percentage composition of a compound? How the percentage of an element is calculated in a compound?

(b) Calculate the percentage composition of each of the following compounds. (Given atomic weights of the elements).

(i) MgSO₄ (ii) C₃H₆O (iii) KMnO₄ (iv) C₆H₆ (v) NaAl(SO₄)₂ (vi) CaCO₃ (vii) CH₄

[Mg = 24, S = 32, O = 16, C = 12, K = 39, Na = 23, Mn = 55, Ca = 40, Al = 27, H = 1]

Question 8

(a) Differentiate between a “limiting reagent” and a “reagent in excess”. How will you identify the limiting reagent in a chemical reaction?

(b) How does a limiting reagent control the amount of the product formed? Give an example.

Question 9

A technician weighs 40 g of sodium. How many moles of formula units are in the sample?