Question

A substance 'x' burns in air with white dazzling light and forms a powder y. This powder 'y' when mixed with water and tested with red litmus, turned it blue. Ne

Answer 1

your answer ↓

White dazzling light(magnesium) from this we can conclude that when magnesium burns in air it gives white dazzling light and forms a powder

2Mg+o2→2Mgo

when mixed with water it forms magnesium hydroxide and hence turns litmus paper

Answer 2

Answer:

Substance 'X' is magnesium ribbon and powder 'y' is magnesium oxide (MgO).

Explanation:

• When the magnesium ribbon burns, it reacts with the oxygen that is found in air.  Thus, it forms a white powdery compound named magnesium oxide (MgO) with white dazzling light .
• In this chemical reaction, release of energy (heat). So, it is an exothermic reaction.
• The chemical reaction can be written as:

       2Mg (s)  +   O₂ (g)  $\longrightarrow$  2MgO (s)   + energy

• When powder of magnesium oxide is dissolved in water, then magnesium hydroxide is formed.

        MgO (s)  +   H₂O    $\longrightarrow$   Mg(OH)₂

Therefore, magnesium hydroxide is basic in nature, which turns the red litmus paper into blue.