Waec Chemistry Past Questions For Year 2016

Question 21

How many moles of oxygen would contain 1.204 x 10²⁴ molecules?

[Avogadro's constant (NA) = 6.02 x 10²³]

waec 2016

• A. 1
• B. 2
• C. 3
• D. 4

Question 22

The pH of four solutions M,N,Q and R are 2,6,8 and 11 respectively.

Which of the following deductions about the solutions is correct?

waec 2016

• A. The pH of N is increased when the solution is diluted
• B. The pH of Q is increased when the solution is evaporated
• C. M is the most alkaline solution
• D. R is the most acidic solution

Question 23

When NH₄Cl_(s) is dissolved in water, the container feels cold to touch. This implies

waec 2016

• A. The process is endothermic
• B. The process is exothermic
• C. NH₄Cl forms a saturated solution
• D. NH₄Cl is highly soluble in water

Question 24

An aqueous solution of (NH4)2 SO4 is

waec 2016

• A. Acidic
• B. Alkaline
• C. Amphoteric
• D. Neutral

Question 25

The energy which accompanies the addition of an electron to an isolated gaseous atom is

waec 2016

• A. Atomization
• B. Electronegativity
• C. Electron affinity
• D. Ionization