Question

sheila went shopping to the supermarket and picked a bottle each of common salt,bakingsoda and a packet of white packet of white powder whose name tag got misplaced . she added a little water to the powder and found brisk effervesence of gas that put out a burning candle

Answer 1

Answer:

The white powder that Sheila picked is also baking powder, NaHCO₃.

The gas that puts out a burning candle is Carbon dioxide, CO₂

Explanation:

When water reacts baking powder, there is effervescence due to the production of a gas. The gas is carbon dioxide, since with a flame test, it puts out the flame/ the burning candle.

Reaction of water and baking powder liberates carbon dioxide, which puts of the  burning candle that Sheila tested the gas with.

Here is the equation for the reaction between water (H₂O) and baking soda (NaHCO₃):

                 2NaHCO3 + H2O ⇒ 2CO2 + 2NaOH + H20

Therefore the white powder in the white packet is baking powder, NaHCO₃ and the gas liberated when water is added is carbon dioxide (CO₂)