ICSE ICSE Class 8 - CISCE Question Bank Solutions

 Fill in the blank.
 The formation of gas bubbles in a liquid during a reaction is called ......................

Fill in the blank.

The reaction between an acid and a base is called ..................

Fill in the blank

 A catalyst either ................or ............... the rate of a chemical change but itself remains ............... at the end of the reaction.

Water is used as a cooling agent.

Give reason of Water pipes burst in severe winter.

Give reason of Ice floats on water.

 Give reason for Sea water does not freeze at 0°C.

How does the anomalous expansion of water help aquatic organisms in cold climates?

Classify the following reaction as combination, decomposition, displacement, precipitation and neutralization. Also balance the equation.

\[\ce{NH3_{(g)} + HCl_{(g)} -> NH4Cl_{(s)}}\]

Classify the following reaction as combination, decomposition, displacement, precipitation and neutralization. Also balance the equation.

\[\ce{CuSO4_{(aq)} + H2S_{(s)} -> CuS_{(s)} + H2SO4_{(l)}}\]

Define precipitation reaction.

Define neutralization.

Write the missing reactants and products and balance the equations.

NaOH + ............... `→` NaCI + ...................

Write the missing reactants and products and balance the equations.

\[\ce{KClO3 ->[heat]}\] ___________+ ____________

Write the missing reactants and products and balance the equations.

................+ HCI `→` NaCI + `"H"_2"O"` + .........................

What do you observe when Iron nail is kept in copper sulphate solution for sometime.

Give reason .

A person suffering from acidity is advised to take an antacid.

Give reason.

Acidic soil is treated with quick lime.

Give a reason.

Wasp sting is treated with vinegar.

What are oxides ?