Chemistry
Describe the two colour changes that take place when moist blue litmus is placed in a gas jar of chlorine. What are these colour changes that take place when chlorine water is exposed to sunlight?
Answer
Chlorine turns moist blue litmus red and finally bleaches it i.e., decolourizes it.
When chlorine water is exposed to sunlight, it changes to colourless from greenish yellow. This colour change happens because chlorine reacts with water to form hypochlorous acid which further breaks to form hydrochloric acid and oxygen gas.
Cl2 + H2O ⟶ HClO + HCl
HClO ⟶ HCl + [O]
[O] + colouring matter ⟶ bleached product
Related Questions
State what you observe when a piece of moist blue litmus paper is placed in a gas jar of chlorine.
For the elements sodium and phosphorous, state the following
(a) the formula of the chloride of each element,
(b) the physical state of each chloride at room temperature (i.e., solid, liquid or gas), and
(c) the nature of bonding of each chloride (i.e., ionic or covalent)
Write correctly a balanced equation for the following 'word equation':
Calcium carbonate + Hydrochloric acid ⟶ Calcium chloride + water + Carbon dioxide
In each case, describe one chemical test applied to the following substances, which would enable you to distinguish between them : carbon dioxide gas and hydrogen chloride gas