Chemical Reaction and Equation

When Lead Nitrate reacts with potassium iodide, Yellow precipitate of ............. is formed

• PbI₂

• KNO₃

• Pb(NO₃)₂

• PbIO₃

Which of the following is not a chemical reaction?

• Souring of milk

• Dissolution of sugar in water

• Rusting of iron

• Digestion of food in our body

Which of the following is not a thermal decomposition reaction

• 2FeSO₄ →Fe₂O₃ +SO₂ + SO₃

• 2H₂O→2H₂ + O₂

• ZnCO₃→ZnO + CO₂

• 2KClO₃→2KCl + 3 O₂

Combustion is an .................Process

• Endothermic

• Exothermic

• Both (a) and (b)

• None of the above

Which of the formula of rust is

• Fe₂O₃

• Fe₃O₄

• Fe₂O₃.nH₂O

• Fe₃O₄.nH₂O

Copper on exposure to air reacts with moisture and carbon dioxide to develop a green layer which is chemically

• Basic Copper carbonate

• Copper sulphate

• Copper Nitrate

• Copper Oxide

When dilute hydrochloric acid is added to granulated zinc placed in a test tube , the observation made is

• The surface of the metal turns shinning

• The reaction mixture turns milky

• Greenish yellow gas is evolved

• the colorless and odorless gas evolve

Which of the following is an example of displacement reaction?

• 2 KClO₃→KCl + O₂

• 2H₂ + O₂ →2 H₂O

• Zn + 2 HCl → ZnCl₂ + H₂

• N₂ + 3 H₂ → 2 NH₃

What will happen when we add iron nail into copper sulphate solution

• Blue color of the solution fades

• Reddish color appears on iron nail

• Color of the solution turns green after some time

• All of these

Burning of magnesium ribbon is a

• Chemical reaction

• Exothermic reaction

• A white color powder forms

• All of these