English Medium कक्षा १० - CBSE Question Bank Solutions for Science

State whether the following statement is true or false:
Non-metals react with dilute acids to produce a gas which burns with a 'pop' sound.

From amongst the metals sodium, calcium aluminium, copper and magnesium, name the metal:
(i) which reacts with water only on boiling, and
(ii) another which does not react even with steam.

What changes in the colour of iron nails and copper sulphate solution do you observe after keeping the iron nails dipped in copper sulphate solution for about 30 minutes?

What name is given to those metal oxides which show basic as well as acidic behaviour?

Name two metals which form amphoteric oxides.

A copper coin is kept immersed in a solution of silver nitrate for some time. What will happen to the coin and the colour of the solution?

Name the metal which has been placed at the bottom of the reactivity series.

Name the metal which has been placed at the top of the reactivity series.

Name the metal which has been placed just below copper in the reactivity series.

Which of the two metals is more reactive: copper or silver?

Write equation for the reaction of sodium with oxygen.

Write equation for the reaction of magnesium with oxygen.

What will happen if a strip of zinc is immersed in a solution of copper sulphate?

What will happen if a strip of copper is kept immersed in a solution of silver nitrate (AgNO₃)?

How would you show that silver is chemically less reactive than copper?

Give reason for the following:
Blue colour of copper sulphate solution is destroyed when iron filings are added to it.

Explain why, the surface of some metals acquires a dull appearance when exposed to air for a long time.

Complete and balance the following equation:

Na  +  O₂ →

Complete and balance the following equation:

Na₂O  +  H₂O →

Complete and balance the following equation: