State PCS PYQPrelims 2022

BPSC – Combined Competitive Examination · প্রশ্ন 96

Which of the following is called 'quicklime'?

  1. CaCO₃
  2. Ca(OH)₂
  3. CaCl₂
  4. CaO
  5. None of the above / More than one of the above
উত্তর দেখান ও ব্যাখ্যা

উত্তর: (D) CaO

ব্যাখ্যা

Heating limestone gives quicklime (CaO); adding water gives slaked lime Ca(OH)₂.

  • (A) ভুল

    Wrong: limestone.

  • (B) ভুল

    Wrong: slaked lime.

  • (C) ভুল

    Wrong: calcium chloride.

  • (D) সঠিক

    Correct: calcium oxide is quicklime.

  • (E) ভুল

    Wrong: only one of the options A–D is correct.