Assertion –Reason type questions –
In the following questions, a statement of assertion followed by a statement of reason is given . Choose the correct answer out of the following choices :
11. ASSERTION : A single C12 atom has a mass exactly 12 amu and a mole of these atoms has a mass of exactly 12 grams.
Reason : A mole of atoms of any element has a mass in gram equal to its atomic mass.
12. ASSERTION : In a gaseous reaction , the ratio of volumes of the reactants and gaseous products is in agreement with their molar ratio.
Reason : Volume of gas is inversely proportional to its moles at particular temperature and
pressure.
13. ASSERTION : The standard unit for expressing the mass of atom is amu.
Reason : amu is also called avogram.
14. ASSERTION : Equal mole of different substances contain the same number of constituent
particles.
Reason : Equal weights of different substances contain the same number of constituent particles.
15. Empirical and molecular formula of Na2CO3 is same.
Reason : Na2CO3 does not not form hydrates.
16. How many moles of KI are required to produce 0.4 moles of K2HgI4 ?
a. 0.4 b. 0.8 c. 3.2 d. 1.6
17. Two grams of sulphur is completely burnt in oxygen to form SO2.In this reaction,what is volum
( in litres ) of oxygen consumed at STP?( At .wt. of sulphur & oxygen are 32 and 16 ) .
a. 16 / 22.414 b. 22.414 / 16 c. 22.414 / 32 d. 32 / 22.414
18. 3 gm of an oxide of metal is converted to chloride completely & it yielded 5 gm of chloride.The
equivalent weight of metal is :
a. 20 b. 12 c. 3.325 d. 33.25
19. The number of moles of hydroxide ( OH–) ions in 0.3 litre of 0.005 m solution of Ba (OH)2 is :
a. 0.005 b. 0.003 c. 0.0015 d. 0.007
20. Dulong & petit’s law is valid only for :
a. metals b. non-metals c. gaseous elements d. solid elements 1x 20
21. Calculate vol. of SO2 gas at STP which contain 3.01 x 1023 molecules.
22. What weight of H2S gas at STP occupy 112 c.c. vol.
23. Calculate the number of atoms of the constituent element in 53 gm. Of Na2CO3 . 2x3
24. Chlorophyll contain 2.68% of Mg by mass .Calculate number of Mg atom in 2..00gm of chlorophyll?
25. Find out Molarity of a solution 500 cc of which contains 2.45 g of H2SO4?
26.Find out number of atoms in 34 amu ofNH3 ?
27. A compound contain C = 41.37 % , H = 5.75 % ,N = 16.09 % ,V.D. = 43.3 .Calculate
Molecular formula .
28.Define –
(a) SI definition of 1 mole
(b) Low of constant composition
(c) Normality 3x 5