ICSE ICSE Class 7 - CISCE Question Bank Solutions

What are noble gases? Name all in the order of their increasing density.   

State one use  of helium  

State one use of argon    

State the composition and two uses of given alloy:

Stainless steel

State the composition and two uses of given alloy:

Duralumin

What are oxides ? 

Give two examples of metallic oxides.

What do you observe when Sulphur is heated and then tested with moist blue and red litmus – paper?

Complete and balance the following chemical equation.

\[\ce{KClO3 ->[heat]  ??   + O2}\]

Which one of the following is most likely to be corroded?

What happens when the mercuric oxide is heated?

Classify Copper oxide. Also give a balanced equation to prepare it.

Classify Sulphur dioxide. Also give a balanced equation to prepare it.

Classify Magnesium oxide. Also give a balanced equation to prepare it.

How will you prove that oxide formed by sulphur is acidic in nature?

Write word equation for the following molecular equation:

CuCo₃ → CuO + CO₂ [g]

Word equation:

State the characteristics or indications occurring in the above reaction.

Write word equation for the following molecular equation:

\[\ce{CaCO3 + 2HCl ->[\triangle] CaCl2 + H2O + CO2 [g]}\]

Word equation:

State which characteristic does [g] in the above reaction indicate. The word equation of:

Write word equation for the following molecular equation:

\[\ce{NH3 [g] + HCl [g] ⇌ NH4Cl [s]}\]

Word equation:
State which characteristic is observed in the above reaction.

Give an-example of a similar above characteristic, seen between two other gaseous reactants.

Write word equation for the following molecular equation:

Na₂SO₃ + 2HCl [dil.] → 2NaCl + H₂O + SO₂ [g] 

Write word equation for the following molecular equation:

FeSO₄ + 2NaOH →Na₂SO₄ + Fe(OH)₂ ↓

Word equation:

State why [↓] indication is seen after Fe(OH)₂ and not after Na₂SO4