Question

14. Assertion: Rusting of iron is a chemical change.
The chemical properties of hydrated Fe2O3 are different from
iron and oxygen.
15. Why do we store silver chloride in dark coloured bottle?
16. A metal when exposed to air forms black coating over it. Name the process
and the metal compound formed by the process.
17. Potato chips manufacturers fill the packet of chips with nitrogen gas. Give
reason.
18.. When barium hydroxide is mixed with ammonium chloride, a fall in
temperature is observed. Why?
(3 Mark Questions)
1. Write the chemical equation of the reaction with an example each in which the
following change has taken place.
a) change in temperature
b) evolution of gas
c) formation of precipitate
2. A white salt on heating decomposes to give brown fumes and yellow residue is
left behind. Name the salt. Write the reaction involved and identify the type of
reaction.
3. In a test tube, hydrochloric acid is poured over a few zinc granules. List two
observations that suggest that a chemical reaction has ocured. Write the
balanced chemical equation.
4.
What is observed when a solution of potassium iodide is added to a solution
of lead nitrate taken in a test tube? Write a balanced chemical equation to
represent the above reaction and identify the type of reaction.
5.
Name the type of reactions that take place during the process of
digestion of food. How do they occur in our body?​

Answer 1

Answer:

14. Assertion: Rusting of iron is a chemical change.

The chemical properties of hydrated Fe2O3 are different from

iron and oxygen.

15. Why do we store silver chloride in dark coloured bottle?

16. A metal when exposed to air forms black coating over it. Name the process

and the metal compound formed by the process.

17. Potato chips manufacturers fill the packet of chips with nitrogen gas. Give

reason.

18.. When barium hydroxide is mixed with ammonium chloride, a fall in

temperature is observed. Why?

(3 Mark Questions)

1. Write the chemical equation of the reaction with an example each in which the

following change has taken place.

a) change in temperature

b) evolution of gas

c) formation of precipitate

2. A white salt on heating decomposes to give brown fumes and yellow residue is

left behind. Name the salt. Write the reaction involved and identify the type of

reaction.

3. In a test tube, hydrochloric acid is poured over a few zinc granules. List two

observations that suggest that a chemical reaction has ocured. Write the

balanced chemical equation.

4.

What is observed when a solution of potassium iodide is added to a solution

of lead nitrate taken in a test tube? Write a balanced chemical equation to

represent the above reaction and identify the type of reaction.

5.

Name the type of reactions that take place during the process of

digestion of food. How do they occur in our body?