A mixture of gases contains H2 and O2 gases in the ratio of 1:4 (w/w). What is the molar ratio of the two gases in the mixture?

(a) 1:4              (b) 4:1              (c) 16:1               (d) 2:1

Concept Questions :-

Moles, Atoms & Electrons
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

If Avogadro number NA, is changed from 6.022 x 1023 mol-1 to 6.022 x 1020 mol-1 this would change

(a) the definition of mass in units of grams

(b) the mass of one mole of carbon

(c) the ratio of chemical species to each other in a balanced equation

(d) the ratio of elements to each other in a compound

Concept Questions :-

Moles, Atoms & Electrons
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

20.0 g of a magnesium carbonate sample decomposes on heating to give carbon dioxide and 8.0 g magnesium oxide. What will be the percentage purity of magnesium carbonate in the sample? (Atomic weight of Mg = 24)

(a) 75

(b) 96

(c) 60

(d) 84

Concept Questions :-

Equation Based Problem
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

What is the mass of precipitate formed when 50 mL of 16.9% solution of AgNO3 is mixed with 50 mL of 5.8% NaCl solution?

(Ag = 107.8, N = 14, O = 16, Na= 23,Cl=35.5)

(a) 28 g

(b) 3.5 g

(c) 7 g

(d) 14 g

Concept Questions :-

Equation Based Problem
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The number of water molecules is maximum in

(a) 18 molecules of water

(b) 1.8 g of water

(c) 18 g of water

(d) 18 moles of water

Concept Questions :-

Moles, Atoms & Electrons
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Mole fraction of the solute in a 1.00 molal aqueous solution is

(a) 0.0177                    (b) 0.0344

(c) 1.7700                    (d) 0.1770

High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

25.3 g of Sodium carbonate Na2CO3 is dissolved in enough water to make 250 mL of solution. If sodium carbonate dissociates completely, molar concentration of sodium ion, Na+ and carbonate ion ${\mathrm{CO}}_{3}^{2-}$ are respectively (Molar mass of Na2CO3 = 106 g mol-1)

(a) 0.955 M and 1.910 M

(b) 1.910 M and 0.955 M

(c) 1.90 M and 1.910 M

(d) 0.477 M and 0.477 M

Concept Questions :-

Concentration Based Problem
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

The number of atoms in 0.1 mole of a triatomic gas is (NA=6.02 x1023mol-1)
(a) 6.026 x 1022

(b) 1.806x1023

(c) 3.600 x 1023

(d) 1.800 x 1022

Concept Questions :-

Moles, Atoms & Electrons
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

What is the [OH-] in the final solution prepared by mixing 20.0 mL of 0.050 M HCl with 30.0 mL of 0.10 M Ba(OH)2?
(a) 0.10 M
(b) 0.40 M
(c) 0.0050 M
(d) 0.12 M

Concept Questions :-

Concentration Based Problem
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

10 g of hydroen and 64g of oxygen were filled in a steel vessel and exploded. Amount of water produced in this reaction will be
(a) 2 mol
(b) 3 mol
(c) 4 mol
(d) 1 mol

Concept Questions :-

Equation Based Problem