English Medium कक्षा १० - CBSE Question Bank Solutions for Science

State and explain Fleming's right hand rule.

Name and state the rule to find the direction of current induced in a coil due to its rotation in a magnetic field.

State two characteristics of the chemical reaction which takes place when dilute sulphuric acid is poured over zinc granules.

Why does the colour of copper sulphate solution change when an iron nail is kept immersed in it?

What type of chemical reaction is represented by the following equation?

\[\ce{A + BC -> AC + B}\]

What type of chemical reaction is represented by the following equation?

\[\ce{A2O3 + 2B -> B2O3 + 2A}\]

Which of the following is a combination and which is a displacement reaction?

1. \[\ce{Cl2 + 2KI -> 2KCl + I2}\]
2. \[\ce{2K + Cl2 -> 2KCl}\]

What type of reaction is represented by the following equation?

\[\ce{2Na + 2H2O -> 2NaOH + H2}\]

What type of reaction is represented by the following equation?

\[\ce{Mg + CuSO4 -> MgSO4 + Cu}\]

What is meant by a displacement reaction? Explain with the help of one example.

What happens when a piece of iron metal is placed in copper sulphate solution? Name the type of reaction involved.

What happens when a zinc strip is dipped into a copper sulphate solution?

1. Write the equation for the reaction that takes place.
2. Name the type of reaction involved.

What happens when a zinc strip is dipped into a copper sulphate solution?
Name the type of reaction involved.

A strip of metal X is dipped in a blue coloured salt solution YSO₄. After some time, a layer of metal Y from the salt solution is formed on the surface of metal strip X. Metal X is used in galvanisation whereas metal Y is used in making electric wires. Metal X and metal Y together form an alloy Z.

1. What could metal X be?
2. What could metal Y be?
3. Name the metal salt YSO₄.
4. What type of chemical reaction takes place when metal X reacts with salt solution YSO₄? Write the equation of the chemical reaction involved.
5. Name the alloy Z.

When a black metal compound XO is heated with a colourless gas Y₂, then metal X and another compound Y₂O are formed. Metal X is red-brown in colour which does not react with dilute acids at all. Gas Y₂ can be prepared by the action of a dilute acid on any active metal. The compound Y₂O is a liquid at room temperature which can turn anhydrous copper sulphate blue.

1. What do you think is metal X?
2. What could be gas Y₂?
3. What is compound XO?
4. What is compound Y₂O?
5. Write the chemical equation of the reaction which takes place on heating XO with Y₂.
6. What type of chemical reaction is illustrated in the above equation?

When a strip of red-brown metal X is placed in a colourless salt solution YNO₃ then metal Y is set free and a blue coloured salt solution X(NO₃)₂ is formed. The liberated metal Y forms a shining white deposit on the strip of metal Х.

1. What do you think metal X is?
2. Name the salt YNO₃.
3. What could be metal Y?
4. Name the salt X(NO₃)₂.
5. What type of reaction takes place between metal X and salt solution YNO₃?

The colour of an aqueous solution of zinc sulphate as observed in the laboratory is:

(1) Green 

(2) Yellow 

(3) Blue 

(4) Colourless

To show that zinc is a more active metal than copper, the correct procedure is to: 

(1) add dilute nitric acid on strips of both the metals. 

(2) observe transmission of heat through strips of zinc and copper. 

(3) prepare solution of zinc sulphate and hang strip of copper into it. 

(4) prepare solution of copper sulphate and hang strip of zinc into it. 

What is observed after about 1 hour of adding the strips of copper and aluminium separately to the ferrous sulphate solution filled in two beakers? Name the reaction if any change in colour is noticed. Also, write a chemical equation for the reaction.

Identify the type of reaction taking place in the following case and write the balanced chemical equation for the reaction.
Zinc reacts with silver nitrate to produce zinc nitrate and silver.