Basic Concepts of Chemistry Practice Questions - DPP for JEE

 Page 1


PART-I (Single Correct MCQs)
1. The weight of NaCl decomposed by 4.9g of H
2
SO
4
, if 6 g of sodium
hydrogen sulphate and 1.825 g of HCl, were produced in the reaction is:
(a) 6.921 g
(b) 4.65 g
(c) 2.925 g
(d) 1.4 g
2. 6.02 × 10
20
 molecules of urea are present in 100 ml of its solution. The
concentration of urea solution is
(a) 0.02 M
(b) 0.01 M
(c) 0.001 M
(d) 0.1 M
(Avogadro constant, N
A
 = 6.02 × 10
23
 mol
–1
)
Page 2


PART-I (Single Correct MCQs)
1. The weight of NaCl decomposed by 4.9g of H
2
SO
4
, if 6 g of sodium
hydrogen sulphate and 1.825 g of HCl, were produced in the reaction is:
(a) 6.921 g
(b) 4.65 g
(c) 2.925 g
(d) 1.4 g
2. 6.02 × 10
20
 molecules of urea are present in 100 ml of its solution. The
concentration of urea solution is
(a) 0.02 M
(b) 0.01 M
(c) 0.001 M
(d) 0.1 M
(Avogadro constant, N
A
 = 6.02 × 10
23
 mol
–1
)
3. If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to
be the relative atomic mass unit, the mass of one mole of the substance
will
(a) be a function of the molecular mass of the substance
(b) remain unchanged
(c) increase two fold
(d) decrease twice
4. How many moles of magnesium phosphate, Mg
3
(PO
4
)
2
 will contain
0.25 mole of oxygen atoms?
(a) 1.25 × 10
–2
(b) 2.5 × 10
–2
(c) 0.02
(d) 3.125 × 10
–2
5. A gas occupies a volume of 300 cc at 27°C and 620 mm pressure. The
volume of gas at 47°C  and 640 mm pressure is:
(a) 260 cc
(b) 310 cc
(c) 390 cc
(d) 450 cc
6. Haemoglobin contains 0.33% of iron by weight. The molecular weight
of haemoglobin is approximately 67200. The number of iron atoms (at.
wt. of Fe = 56) present in one molecule of haemoglobin is
(a) 6
(b) 1
(c) 2
Page 3


PART-I (Single Correct MCQs)
1. The weight of NaCl decomposed by 4.9g of H
2
SO
4
, if 6 g of sodium
hydrogen sulphate and 1.825 g of HCl, were produced in the reaction is:
(a) 6.921 g
(b) 4.65 g
(c) 2.925 g
(d) 1.4 g
2. 6.02 × 10
20
 molecules of urea are present in 100 ml of its solution. The
concentration of urea solution is
(a) 0.02 M
(b) 0.01 M
(c) 0.001 M
(d) 0.1 M
(Avogadro constant, N
A
 = 6.02 × 10
23
 mol
–1
)
3. If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to
be the relative atomic mass unit, the mass of one mole of the substance
will
(a) be a function of the molecular mass of the substance
(b) remain unchanged
(c) increase two fold
(d) decrease twice
4. How many moles of magnesium phosphate, Mg
3
(PO
4
)
2
 will contain
0.25 mole of oxygen atoms?
(a) 1.25 × 10
–2
(b) 2.5 × 10
–2
(c) 0.02
(d) 3.125 × 10
–2
5. A gas occupies a volume of 300 cc at 27°C and 620 mm pressure. The
volume of gas at 47°C  and 640 mm pressure is:
(a) 260 cc
(b) 310 cc
(c) 390 cc
(d) 450 cc
6. Haemoglobin contains 0.33% of iron by weight. The molecular weight
of haemoglobin is approximately 67200. The number of iron atoms (at.
wt. of Fe = 56) present in one molecule of haemoglobin is
(a) 6
(b) 1
(c) 2
(d) 4
7. In the reaction,
 
(a) 11.2 L H
2
(g) at STP is produced for every mole HCl(aq) consumed
(b) 6 L HCl(aq) is consumed for every 3 L H
2
(g) produced
(c) 33.6 L H
2
(g) is produced regardless of temperature and pressure for
every mole Al that reacts
(d) 67.2 H
2
(g) at STP is produced for every mole Al that reacts.
8. The concentrated sulphuric acid that is peddled commercial is 95%
H
2
SO
4
 by weight. If the density of this commercial acid is 1.834 g cm
–3
,
then find the molarity of this solution.
(a) 17.8 M
(b) 12.0 M
(c) 10.5 M
(d) 15.7 M
9. What is the mass of precipitate formed when 50 mL of 16.9% solution of
AgNO
3
 is mixed with 50 mL of 5.8% NaCl solution ?
(Ag = 107.8, N = 14, O = 16, Na = 23, Cl = 35.5)
(a) 28 g
(b) 3.5 g
(c) 7 g
(d) 14 g
10. Number of valence electrons in 4.2 gram of N
3
? –
 ion is
(a) 4.2 N
A
Page 4


PART-I (Single Correct MCQs)
1. The weight of NaCl decomposed by 4.9g of H
2
SO
4
, if 6 g of sodium
hydrogen sulphate and 1.825 g of HCl, were produced in the reaction is:
(a) 6.921 g
(b) 4.65 g
(c) 2.925 g
(d) 1.4 g
2. 6.02 × 10
20
 molecules of urea are present in 100 ml of its solution. The
concentration of urea solution is
(a) 0.02 M
(b) 0.01 M
(c) 0.001 M
(d) 0.1 M
(Avogadro constant, N
A
 = 6.02 × 10
23
 mol
–1
)
3. If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to
be the relative atomic mass unit, the mass of one mole of the substance
will
(a) be a function of the molecular mass of the substance
(b) remain unchanged
(c) increase two fold
(d) decrease twice
4. How many moles of magnesium phosphate, Mg
3
(PO
4
)
2
 will contain
0.25 mole of oxygen atoms?
(a) 1.25 × 10
–2
(b) 2.5 × 10
–2
(c) 0.02
(d) 3.125 × 10
–2
5. A gas occupies a volume of 300 cc at 27°C and 620 mm pressure. The
volume of gas at 47°C  and 640 mm pressure is:
(a) 260 cc
(b) 310 cc
(c) 390 cc
(d) 450 cc
6. Haemoglobin contains 0.33% of iron by weight. The molecular weight
of haemoglobin is approximately 67200. The number of iron atoms (at.
wt. of Fe = 56) present in one molecule of haemoglobin is
(a) 6
(b) 1
(c) 2
(d) 4
7. In the reaction,
 
(a) 11.2 L H
2
(g) at STP is produced for every mole HCl(aq) consumed
(b) 6 L HCl(aq) is consumed for every 3 L H
2
(g) produced
(c) 33.6 L H
2
(g) is produced regardless of temperature and pressure for
every mole Al that reacts
(d) 67.2 H
2
(g) at STP is produced for every mole Al that reacts.
8. The concentrated sulphuric acid that is peddled commercial is 95%
H
2
SO
4
 by weight. If the density of this commercial acid is 1.834 g cm
–3
,
then find the molarity of this solution.
(a) 17.8 M
(b) 12.0 M
(c) 10.5 M
(d) 15.7 M
9. What is the mass of precipitate formed when 50 mL of 16.9% solution of
AgNO
3
 is mixed with 50 mL of 5.8% NaCl solution ?
(Ag = 107.8, N = 14, O = 16, Na = 23, Cl = 35.5)
(a) 28 g
(b) 3.5 g
(c) 7 g
(d) 14 g
10. Number of valence electrons in 4.2 gram of N
3
? –
 ion is
(a) 4.2 N
A
Substance Molecular  Wt. Mass percent
Na
2
CO
3
106.0 84.8
NaHCO
3
  84.0  8.4
NaCl 58.5  6.8
(b) 0.1 N
A
(c) 1.6 N
A
(d) 3.2 N
A
11. A transition metal M forms a volatile chloride which has a vapour
density of 94.8. If it contains 74.75% of chlorine the formula of the
metal chloride will be
(a) MCl
3
(b) MCl
2
(c) MCl
4
(d) MCl
5
12. A gaseous hydrocarbon gives upon combustion 0.72 g of water and
3.08 g. of CO
2
. The empirical formula of the hydrocarbon is :
(a) C
2
H
4
(b) C
3
H
4
(c) C
6
H
5
(d) C
7
H
8
13. Following is the composition of a washing soda sample :
On complete reaction with excess HCl, one kilogram of the washing soda
will evolve:
(a) 9 mol of CO
2
Page 5


PART-I (Single Correct MCQs)
1. The weight of NaCl decomposed by 4.9g of H
2
SO
4
, if 6 g of sodium
hydrogen sulphate and 1.825 g of HCl, were produced in the reaction is:
(a) 6.921 g
(b) 4.65 g
(c) 2.925 g
(d) 1.4 g
2. 6.02 × 10
20
 molecules of urea are present in 100 ml of its solution. The
concentration of urea solution is
(a) 0.02 M
(b) 0.01 M
(c) 0.001 M
(d) 0.1 M
(Avogadro constant, N
A
 = 6.02 × 10
23
 mol
–1
)
3. If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to
be the relative atomic mass unit, the mass of one mole of the substance
will
(a) be a function of the molecular mass of the substance
(b) remain unchanged
(c) increase two fold
(d) decrease twice
4. How many moles of magnesium phosphate, Mg
3
(PO
4
)
2
 will contain
0.25 mole of oxygen atoms?
(a) 1.25 × 10
–2
(b) 2.5 × 10
–2
(c) 0.02
(d) 3.125 × 10
–2
5. A gas occupies a volume of 300 cc at 27°C and 620 mm pressure. The
volume of gas at 47°C  and 640 mm pressure is:
(a) 260 cc
(b) 310 cc
(c) 390 cc
(d) 450 cc
6. Haemoglobin contains 0.33% of iron by weight. The molecular weight
of haemoglobin is approximately 67200. The number of iron atoms (at.
wt. of Fe = 56) present in one molecule of haemoglobin is
(a) 6
(b) 1
(c) 2
(d) 4
7. In the reaction,
 
(a) 11.2 L H
2
(g) at STP is produced for every mole HCl(aq) consumed
(b) 6 L HCl(aq) is consumed for every 3 L H
2
(g) produced
(c) 33.6 L H
2
(g) is produced regardless of temperature and pressure for
every mole Al that reacts
(d) 67.2 H
2
(g) at STP is produced for every mole Al that reacts.
8. The concentrated sulphuric acid that is peddled commercial is 95%
H
2
SO
4
 by weight. If the density of this commercial acid is 1.834 g cm
–3
,
then find the molarity of this solution.
(a) 17.8 M
(b) 12.0 M
(c) 10.5 M
(d) 15.7 M
9. What is the mass of precipitate formed when 50 mL of 16.9% solution of
AgNO
3
 is mixed with 50 mL of 5.8% NaCl solution ?
(Ag = 107.8, N = 14, O = 16, Na = 23, Cl = 35.5)
(a) 28 g
(b) 3.5 g
(c) 7 g
(d) 14 g
10. Number of valence electrons in 4.2 gram of N
3
? –
 ion is
(a) 4.2 N
A
Substance Molecular  Wt. Mass percent
Na
2
CO
3
106.0 84.8
NaHCO
3
  84.0  8.4
NaCl 58.5  6.8
(b) 0.1 N
A
(c) 1.6 N
A
(d) 3.2 N
A
11. A transition metal M forms a volatile chloride which has a vapour
density of 94.8. If it contains 74.75% of chlorine the formula of the
metal chloride will be
(a) MCl
3
(b) MCl
2
(c) MCl
4
(d) MCl
5
12. A gaseous hydrocarbon gives upon combustion 0.72 g of water and
3.08 g. of CO
2
. The empirical formula of the hydrocarbon is :
(a) C
2
H
4
(b) C
3
H
4
(c) C
6
H
5
(d) C
7
H
8
13. Following is the composition of a washing soda sample :
On complete reaction with excess HCl, one kilogram of the washing soda
will evolve:
(a) 9 mol of CO
2
(b) 16 mol of CO
2
(c) 17 mol of CO
2
(d) 18 mol of CO
2
14. Arrange the numbers in increasing no. of significant figures.
0.002600, 2.6000, 2.6, 0.260
(a) 2.6 < 0.260 < 0.002600 < 2.6000
(b) 2.6000 < 2.6 < 0.002600 < 0.260
(c) 0.260 < 2.6 < 0.002600 < 2.6000
(d) 0.002600 < 0.260 <  2.6 < 2.6000
15. Dissolving 120 g of a compound (mol. wt. 60) in 1000 g of water gave
a solution of density 1.12 g/mL. The molarity of the solution is:
(a) 1.00 M
(b) 2.00 M
(c) 2.50 M
(d) 4.00 M
16. A gaseous compound of nitrogen and hydrogen contains 12.5% (by
mass) of hydrogen. The density of the compound relative to hydrogen is
16. The molecular formula of the compound is:
(a) NH
2
(b) N
3
H
(c) NH
3
(d) N
2
H
4
17. The amount of BaSO
4
 formed upon mixing 100 mL of 20.8% BaCl
2
solution with 50 mL of 9.8% H
2
SO
4
 solution with 50 mL of 9.8%
H
2
SO
4
 solution will be:
(Ba = 137, Cl = 35.5, S = 32, H = 1 and O = 16)