question_answer 1)

  A substance which gives brick red flame and breaks down on heating to give oxygen and a brown gas is: (a) magnesium nitrate   (b) calcium nitrate           (c) barium nitrate             (d) strontium nitrate

Answer:

  (b) Calcium nitrate on heating breaks up to give oxygen and nitrogen dioxide (a brown coloured gas). It gives brick red colour to the flame. \[Ca{{(N{{O}_{3}})}_{2}}\to CaO+2N{{O}_{2}}+\frac{1}{2}{{O}_{2}}\]