# Which atoms will be found in the products of the following reactions?

## a. Mercury (II) oxide, $H g O$, is heated and decomposes. b. Limestone, $C a C {O}_{3}$, reacts with hydrochloric acid, $H C l$. c. Table sugar, ${C}_{12} {H}_{22} {O}_{11}$ burns in air to form caramel?

Jan 22, 2017

You will only find atoms that were originally present.

#### Explanation:

(a) $H g \mathmr{and} O$
The reaction is $2 H g O \to 2 H g + {O}_{2}$

(b) $C a , C , O , H \mathmr{and} C l$
The reaction is $C a C {O}_{3} + 2 H C l \to C a C {l}_{2} + C {O}_{2} + {H}_{2} O$

(c) $C , H \mathmr{and} O$
A simple reaction equation cannot be written, as much depends on the heating and the completeness of the burning.