Download Mole Concept - Shailendra Kumar Chemistry

PHYSICAL CHEMISTRY
By: Shailendra Kumar
PHYSICAL CHEMISTRY
by: SHAILENDRA KR.
Classes at: -
Meq. Approach
SCIENCE TUTORIALS; Opp. Khuda Baksh Library, Ashok Rajpath, Patna
PIN POINT STUDY CIRCLE; House No. 5A/65, Opp. Mahual Kothi, Alpana Market, Patna
Topic: Mole Concept & Equivalent Concept
01.
The formula weight of an acid is 82.0. 100 cm3 of a solution of this acid containing 39.0 g of the
acid per litre were completely neutralized by 95.0 cm3 of aqueous NaOH containing 40.0 g of
NaOH per litre. What is the basicity of the acid ?
Ans:
n=2
02.
How many millilitre of 0.5 M H2SO4 are needed to dissolve 0.5 g of copper II carbonate ?
Ans:
V = 8.097 mL
03.
Calculate the amount of calcium oxide required when it reacts with 852 g of P4O10.
Ans:
1008 g
04.
Find the normality of H2SO4 having 50 milliequivalents in 2 litre.
Ans:
0.025
05.
Find the weight of NaOH in its 50 milli equivalents.
Ans:
2g
06.
Find the milli equivalent of:
Ans:
(a)
Ca(OH)2 in 74 g.
(b)
NaOH in 20 g.
(c)
H2SO4 in 2.45 g.
(a)
2000
(b)
500
(c)
50
07.
1.35 g of pure Ca metal was quantitatively converted in to 1.88 g of pure CaO. What is atomic
weight of Ca?
Ans:
40.75
08.
1.0 g of metal nitrate gave 0.86 g of metal sulphate. Calculate equivalent weight of metal.
Ans:
38
1.
2.
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House no. 5A/65, Opp. Mahual Kothi, Alpana Market, Patna
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PHYSICAL CHEMISTRY
By: Shailendra Kumar
09.
1.60 g of a metal were dissolved in HNO3 to prepare its nitrate. The nitrate was strongly heated
to give 2 g oxide. Calculate equivalent weight of metal.
Ans:
32
10.
Assume that the nucleus of the F atom is a sphere of radius 5 × 10–13 cm. Calculate the density
of matter in F nucleus.
Ans:
6 × 1013 g mL –1
11.
Calculate the weight of FeO produced from 2 g VO and 5.75 g of Fe2O3. Also report the limiting
reagent.
VO + Fe2O3 ––––→ FeO + V2O5
Ans:
5.17 g, The limiting reagent is one which is used completely i.e., Fe2O3 here
12.
Calculate the volume of O2 and volume of air needed for combustion of 1 kg carbon at STP.
Ans:
9333.35 litre
13.
Copper forms two oxides. For the same amount of copper, twice as much oxygen was used to
form first oxide than to form second one. What is the ratio of the valencies of copper in first and
second oxides ?
Ans:
Valency of Cu in I and II oxides are in the ratio 2:1
14.
Calculate the weight of iron which will be converted into its oxide by the action of 18 g of steam.
Ans:
42 g
15.
Calculate the residue obtained on strongly heating 2.76 g Ag2CO3.
Ans:
2.16 g
16.
A compound contains 28% N and 72% of a metal by weight. Three atoms of metal combine
with two atoms of N. Find the atomic weight of metal.
Ans:
24
17.
The vapour density of a mixture containing NO2 and N2O4 is 38.3 at 27ºC. Calculate the mole of
NO2 in 100 mole mixture.
Ans:
33.48 mole
18.
The vapour density of a mixture containing NO2 and N2O4 is 38.3 at 27ºC. Calculate the mole of
NO2 in 100 g mixture.
Ans:
0.437
19.
A plant virus is found to consist of uniform cylindrical particles of 150 Å in diameter and 5000 Å
long. The specific volume of the virus is 0.75 cm3/g. If the virus is considered to be a single
particle, find its molecular weight.
Ans:
7.095 × 107
1.
2.
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House no. 5A/65, Opp. Mahual Kothi, Alpana Market, Patna
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