Question

1.   When crystals of lead nitrate are heated strongly in a

dry test tube :

      (a)  crystals immediately melt

(b)  a brown residue is left

      (c)  white fumes appear in the tube

(d)  a yellow residue is left

2. Dilute hydrochloric acid is added to granulated zinc

taken in a test tube. The following observations are

recorded. Point out the correct observation.

      (a)  The surface of metal becomes shining

      (b)  The reaction mixture turns milky

      (c)  Odour of a pungent smelling gas is recorded

      (d)  A colourless and odourless gas is evolved

3.   When carbon dioxide is passed through lime water :

      (a)  calcium hydroxide is formed

(b)  white precipitate of CaO is formed

      (c)  lime water turns milky

(d)  colour of lime water disappears.

4.  When a magnesium ribbon is burnt in air, the ash

formed is :

     (a)  black (b)  white

(c)  yellow (d)  pink

5.   In which of the following, heat energy will be evolved?

      (a)  Electrolysis of water

      (b)  Dissolution of NH4Cl in water

      (c)  Burning of L.P.G.

      (d)  Decomposition of AgBr in the presence of sunlight

6.   Rancidity can be prevented by :

      (a)  adding antioxidants

(b)  storing food away from light

      (c)  keeping food in refrigerator

(d)  all of these

Topic : - CHEMICAL REACTION & EQUATION

P. P. SAVANI CENTRE

FOR EXCELLENCE

JEE/NEET/FOUNDATION

Class: 10th

DPP NO. (02)

Date : 29-04-2020

Subject : CHEMISTRY

7.   The reaction of H2

 gas with oxygen gas to form water is

an example of :

      (a)  combination reaction

(b)  redox reaction

(c)  exothermic reaction

(d)  all of these reactions

8.   The reaction in which two compound exchange their

ions to form two new compounds is called :

      (a)  displacement reaction

(b)  combination reaction

      (c)  double displacement reaction

(d)  redox reaction

9.   On immersing an iron nail in CuSO4

 solution for few

minutes, you will observe :

      (a)  no reaction takes place

     (b)  thecolour of solution fades away

     (c)  the surface of iron nails acquire a black coating

      (d)  thecolour of solution changes to green

10. An element X on exposure to moist air turns re

dish-brown and a new compound Y is formed.

The substance X and Y are :

      (a)  X = Fe, Y = Fe2

O3

(b)  X = Ag, Y = Ag2

S

(c)  X = Cu, Y = CuO

(d)  X = Al, Y = Al2

O3​

Answer 1

Answer:

1.a

2.d

3.b

4.c

5.d

7.c

8.a

9.b

10.d