Stoichiometry - Jamb Chemistry Past Questions and Answers

Question 86:

• JAMB 2006

The volume of 2.5 moles of oxygen at s.t.p is
[Molar volume of a gas at s.t.p = 22.4 dm³]

A. 50.0 dm³
B. 84.0 dm³
C. 28.0 dm³
D. 56.0 dm³

Question 87:

• JAMB 2006

What is the molar mass of a substance, if 0.4 mole of the substance has a mass of 25.0g?

A. 62.5 g
B. 40.0 g
C. 6.3 g
D. 2.5 g

Question 88:

• JAMB 2006

2C₂H_2(g) + 5O_2(g) → 4CO_2(g) + 2H₂O_(g)
In the reaction above, the mass of carbon(IV)oxide produced on burning 78 g of ethyne is
[C =12, O = 16, H = 1]

A. 264 g
B. 39 g
C. 352 g
D. 156 g

Question 89:

• JAMB 2006

Na2CO3(g) + 2HCl(aq) → 2NaCl(aq) + H2O(l) + CO2(g)
How many moles of sodium trioxocarbonate (IV) are there in a 25 cm3 solution which required 10cm3 of 0.05 mol dm-3 hydrochloric acid solution to neutralize it?

A. 1.000 mole
B. 0.100 mole
C. 0.010 mole`
D. 0.111 mole

Question 90:

• JAMB 2007

Calculate the number of moles of HCl present in 20cm³ of a 0.75M solution of the acid

A. 0.015 mole
B. 0.038 mole
C. 3.800 moles
D. 1.500 moles