Subject: Chemistry Class: 10th

Time: 2 hours             Total Marks: 60
Name: _____________                      Date: ___________
Subject: Chemistry                                                           Class:  10th
Questions
1 2 3 4 5 6 Total Marks
Marks Obtained
Note: You have four choices for each objective type question as A, B, C & D. The choice which you think is correct, encircle that option. Cutting or overwriting will result in zero mark.
Objective Part
Time Allowed: 15 minutes Total Marks: 12
Q.1. Select the best option and circle it.
i. Kc is called:
 Zero constant   b)  equilibrium constant    c)   reverse constant  d)  all of these
ii. At initial stage the rate of forward reaction is very _____.
 Low    b) speedy        c)  fast      d)  none of these
iii. Oxidation of alkenes produces:
glyoxal b)  glycol c) oxalic acid d) formic acid
iv. The order of reactivity of hydrogen halides with alkenes is:
    HI > HBr b) HBr > HI   
c)       HCl >HBr d) HBr < HCl
v. Which one of the followings is a substitution reaction?
           a)  halogenations of alkynes 
  b) halogenations of alkenes
  c)  halogenations of alkanes
  d) brominating of alkenes
vi. Night blindness is because of deficiency of:
Vitamin A b)  vitamin E c) Vitamin C d) Vitamin D

vii. Which of the following is fat soluble vitamin?
A b) E c) K d) all of the given options
viii. The most important oligosaccharide is:
           a) sucrose 
  b) glucose
  c) fructose
  d) maltose
ix. Global warming causes rising of the sea level. The cause of global warming is:
CO2 gas
SO2 gas
NOx gas
O3 gas
x. Which gas protects the Earth’s surface from ultraviolet radiations?
CO2
CO
N2
O3 
For a reaction between PCl3 and Cl2 to form PCl5. The units of Kc are:
a. mol dm3    b. mol-1 dm3    c. mol-1 dm-3  d. mol dm-3
Acetic acid is used for:
a. medicine b. printing c. preserving food d. flavouring food









Subjective Part
Part-I
Time Allowed: 1 hr: 40 minutes Total marks: 48
Note: Provide the students with extra sheets to solve the subjective part.
Q.2. Attempt any five questions from the following. (5x2=10)
How ozone layer forms in stratosphere?
How acid rain increases the acidity of soil?
How waterborne diseases can be prevented?
Define molecular formula. Give two examples.
Define neutralization reaction and give two examples.
What is an active mass of a reaction?
Write a combination and decomposition reaction of calcium carbonate.
Differentiate between branched chain and straight chain compounds.
Q.3. Attempt any five questions from the following. (6x2=12)         
Prepare ammonia by the ‘Haber’s process’.
Write the formula of petrol and also write its carbon composition.
What is normal acid?
Define the phenomena of isomerism.
What is alkyl radical? Give two examples.
What is gypsum? Write its uses.
What is a weak acid? Give two examples.
State the major sources of CO and CO2 emission.
Give the effects of acid rain.
Q.4. Attempt any five questions from the following. (5x2=10)         
Define soft and hard water.
Explain the Clark’s method for removal of hardness in water.
How are alkyl halides reduced?
Why the alkanes are used as fuel?
Why hydrocarbons are soluble in organic solvents?
Calculate the pH of 0.1 M of KOH.
How is dynamic equilibrium established?
What are irreversible reactions?
Part-II
Note: Attempt any two questions. (2x9=18)
Q.5. (a). Give some disadvantages of hard water. (5)
        (b). Write a note on the treatment of sewage water.                                (4)
Q.6. (a) What are the uses of organic compounds? (5)
        (b) Explain the sources and uses of proteins. (4)
Q.7. (a). Describe the Ohm’s Law. (5)
        (b). What type of reactions are given by alkanes?
       Explain with reference to halogenation of alkanes. (4)

















Answer key
Q.1. Select the best option.
b
c
b
a
c
a
b
a
a
d
b
c