Free account: track your progress — Sign up free

WAEC Chemistry 2011 Objective — Question 14

Question 14 of 50 from the West African Examinations Council (WAEC) Chemistry 2011 Objective paper, with the correct answer and a full explanation.

Advertisement

When element ₂₀A combines with element ₈Y,

  • A. A. a covalent compound, AY is formed
  • B. B. an ionic compound, AY is formedCorrect
  • C. C. an ionic compound, A2Y is formed
  • D. D. a covalent compound, AY2 is formed

Explanation

20A = 2,8,8,2, so A has a combining power of 2 (loses two electrons). 8Y = 2,6, so Y also has a combining power of 2 (gains two electrons). Using the combining powers, A2+Y2- = A2Y2 = AY. Since electron transfer is involved, the compound formed is ionic.

Advertisement

Sign up free to unlock

  • Score tracking
  • Practice history
  • Saved questions
  • Progress dashboard
  • Personalized sessions
  • Weak-topic breakdown

…and/or go further with premium services and No Ads.