Double substitution reactions between two salt solutions are accompanied by the formation of……………..

• A metal

• a precipitate

• an oxide

• a non metal

Carbon dioxide gas evolves during thermal decomposition of……………….. Compound

•   CuSO₄        

• CuCO₃   

• Cu(OH)₂

• HgO

 

Active metals react with water as they substitute hydrogen of water forming …………… and hydrogen gas evolves

• metal oxide

• metal nitrate

• metal hydroxide

• metal nitrite

 

Aluminium practically delays in its reaction with hydrochloric acid due to the presence of…………………….. Layer

• Aluminium chloride

• aluminium oxide

• aluminium hydroxide

• aluminium sulphate

 

All of the following represents reduction process except:……………..

• Decreasing oxygen

• gains electrons

• combination with hydrogen

• losing electrons

 

Clear lime water turbidss on passing………………. gas through it.

• nitrogen dioxide

• sulphur dioxide

• carbon dioxide

• oxygen

 

in the reaction : Mg + 2HCl  ----------->  Mg Cl₂ + H₂

the oxidizing agent is ……………

• Magnesium           

•  hydrogen            

• chlorine

Na₂CO₃ + ................... -------------->2Na Cl + H₂O + CO₂

• HCl

• H₂O

• Ag Cl

• H₂SO₄

Illustrate by balancing chemical equation the effect of heat on copper carbonate

..................................Gas evolves when sodium reacts with water while on heating blue copper sulphate……………….. Gas evolves

• O_{2 -} H₂

• H_{2 -} SO₃

• H_{2 -} O₂

• O_{2 -} SO₃