-
Calculate the mass of glucose molecule
\[({{C}_{6}}{{H}_{12}}{{O}_{6}})\].
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-
Calculate the amount of water produced by the combustion of
16 g of methane.
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-
A compound contains 4.07% hydrogen,
24.27% carbon and 71.65% chlorine. Its molecular mass is 98.96.
What are its empirical and molecular formula?
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-
How many moles of methane are required to produce \[22g\,\,C{{O}_{2}}\]
after combustion?
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-
\[50kg\,{{N}_{2}}(g)\] and \[10kg\]of \[{{H}_{2}}(g)\] are
mixed to produce \[N{{H}_{3}}(g)\]. Calculate the amount of \[N{{H}_{3}}(g)\]
formed. Identify the limiting reagent in the production of \[N{{H}_{3}}\] in
this situation.
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-
A solution is prepared by adding 2 g of a substance A to 18 g
of water. Calculate the mass percent of the solute.
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-
A solution of \[NaOH\] is prepared by dissolving 4g of it in
\[200c{{m}^{3}}\] of the solution. Calculate the molarity of the solution.
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-
The density of 3M solution of \[\text{NaCl}\] is \[1.25g\,m{{L}^{-1}}\]Calculate
the molality of solution.
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-
Give molecular mass
of the following compounds:
(i) \[{{H}_{2}}O\] (ii)
\[C{{O}_{2}}\] (iii) \[C{{H}_{4}}\]
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-
Calculate the percentage composition of each element in
Sodium sulphate \[N{{a}_{2}}S{{O}_{4}}.\]
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-
Determine the molecular formula of an oxide of iron in which
the mass percentage of iron and oxygen are 69.9 and 30.1 respectively.
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-
Calculate the amount of carbon
dioxide that could be produced when:
(i) 1 mole of carbon
is burnt in air.
(ii) 1 mole of
carbon is burnt in 16 g of dioxygen.
(iii) 2 moles of carbon are burnt in 16 g of dioxygen.
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-
Calculate the mass
of sodium acetate \[(C{{H}_{3}}COONa)\] required to make 500 mL of 0.315 M
solution. Given that the molar mass of sodium acetate is 82.
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-
Calculate the concentration of nitric acid in moles per
litre in a sample which has density, \[1.41g\,m{{L}^{-1}}\] and has mass per
cent of nitric acid in it being 69%.
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-
How much copper can be obtained from 100 g of copper sulphate?
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-
Determine the molecular formula of an oxide of iron in which
the mass per cent of iron and oxygen are 69.9 and 30.1 respectively.
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-
Calculate the atomic
mass (average) of chlorine using the following data:
% Natural Abundance Molar mass
\[^{35}Cl\]
75.77 34.9689
\[^{37}Cl\]
24.23 36.9659
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In three moles of
ethane \[({{C}_{2}}{{H}_{6}}),\] calculate the fallowing:
(i) No. of
moles of carbon atoms
(ii) No. of
moles of hydrogen atoms
(iii) No. of
molecules of ethane
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What is the
concentration of sugar \[({{C}_{12}}{{H}_{22}}{{O}_{11}})\] in \[mol\,{{L}^{-1}}\]
if its 20 g are dissolved in enough water to make a final volume upto \[2L?\]
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If the density of methanol is \[0.793\,\,kg\,\,{{L}^{-1}}\].
What is its volume needed for making 2.5L of its 0.25M solution?
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-
Pressure is
determined as force per unit area of the surface. The S.I. unit of pressure,
pascal is as shown below:
\[1\,Pa=1N{{m}^{-2}}\]
If mass of air at
sea level is 1034 g\[c{{m}^{-2}}\], calculate the pressure in pascal.
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-
What is S.I. unit of mass? How is it defined?
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-
Match the following
prefixes with their multiples:
(i)
micro
\[{{10}^{6}}\]
(ii)
deca
\[{{10}^{9}}\]
(iii)
mega
\[{{10}^{-6}}\]
(iv)
giga
\[{{10}^{-15}}\]
(v)
femto
10
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-
What do you mean by significant figures?
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-
A sample of drinking
water was found to be severely contaminated with chloroform, \[CHC{{l}_{3}}\], supposed
to be carcinogenic in nature. The level of contamination was 15 ppm (by mass):
(i) Express
this in per cent by mass.
(ii) Determine the
molality of chloroform in the water sample.
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Express the
following into scientific notation:
(i) 0.0048
(ii) 234000
(iii)
8008 (iv) 500.0
(v) 6.0012
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-
How many significant
figures are present in the following?
(i)
0.0025 (ii) 208
(iii)
5005 (iv) 126000
(v) 500.0 (vi)
2.0034
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-
Round up the fallowing
upto three significant figures:
(i)
34.216 (ii) 10.4107
(iii) 0.04597 (iv)
2808
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The following data
are obtained when dinitrogen and dioxygen react together to form defferent
compounds :
Mass dinitrogen
Mass of dioxygen
(i)
14 g
16 g
(ii)
14 g
32 g
(iii)
28 g
32 g
(iv)
28 g
80 g.
(a) Which
law of chemical combination is obeyed by the above experimental data?
Given its
statement,
(b) Fill in
the blanks in the following conversions:
(i) 1 km =..
mm =..... pm
(ii) 1 mg = .....
kg = ..... ng
(iii) 1 mL =..... L =.....
\[d{{m}^{3}}\]
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-
If the speed of light is \[3\times {{10}^{8}}m{{s}^{-1}}\], calculate
the distance covered by light in 2.00 ns.
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-
In a reaction,
\[A+{{B}_{2}}\to A{{B}_{2}}\]
Identify the
limiting reagent, if any, in the following reaction mixtures
(i) 300 atoms
of A + 200 molecules of \[{{B}_{2}}\]
(ii) \[\text{2
mol A + 3 mol }{{\text{B}}_{\text{2}}}\]
(iii) \[100\,\,atoms\,of\,A+100\,molecules\,of\,{{B}_{2}}\]
(iv) \[5molA+2.5mol{{B}_{2}}\]
(v) \[2.5molA+5mol{{B}_{2}}\]
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Dinitrogen and
dihydrogen react with each other to produce ammonia according to the following
chemical equation :
\[{{N}_{2}}(g)+3{{H}_{2}}(g)\to 2N{{H}_{3}}(g)\]
(i) Calculate
the mass of ammonia produced if \[2\times {{10}^{3}}g\] dinitrogen reacts with \[1\times
{{10}^{3}}g\] of dihydrogen.
(ii) Will any of the
two readouts remain unreacted?
(iii) If yes, which one and what would be its mass?
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How are 0.50 mol \[N{{a}_{2}}C{{O}_{3}}\] and 0.50 M \[N{{a}_{2}}C{{O}_{3}}\]
different?
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-
If ten volumes of dihydrogen gas reacts with five volumes dioxygen
gas, how many volumes of water vapour would be produced?
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-
Convert the following into
basic units:
(i) 28.7 pm (ii) 15.15 pm (iii) 25365 mg
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Which of the
following has largest number of atoms?
(i) 1 g of Au
(ii) 1 g of Na
(iii) 1 g of K (iv)
1 g of \[C{{l}_{2}}\]
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-
Calculate the molality of a solution of ethanol in water in which
the mole fraction of ethanol is 0.04.
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-
What will be the mass of one \[{{\,}^{12}}C\] atom in gram?
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-
How many significant
figures should be present in the answer of the following calculations?
(i) \[\frac{0.02856\times
298.15\times 0.112}{0.5785}\]
(ii) \[5\times
5.364\]
(iii) \[0.0125+0.7864+0.0215\]
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Use the data given
in the following table to calculate the molar mass of naturally occurring argon
isotopes:
Isotope
Isotopic
molar mass
Abundance
\[{{\,}^{36}}Ar\]
35.96755 g \[mo{{l}^{-1}}\]
0.337%
\[{{\,}^{38}}Ar\]
37.96272 g \[mo{{l}^{-1}}\]
0.063%
\[{{\,}^{40}}Ar\]
39.9624 g \[mo{{l}^{-1}}\]
99.6%
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Calculate the number
of atoms present in:
(i) 52 moles
of He
(ii) 52 amu
He
(iii) 52 g
He
(Atomic mass of
Helium is 4 amu).
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A welding fuel gas contains carbon and hydrogen only burning
a sample of it in oxygen gives 3.38 g carbon dioxide, 0.69 g of water and no
other products. A volume of 10 L (measured at STP) of this welding gas is found
to weigh 11.6 g. Calculate: (i) Empirical formula (ii) Molar mass of the gas
(iii) Molecular formula.
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Calcium carbonate
reacts with aqueous \[HCl\] to give \[CaC{{l}_{2}}\] and \[C{{O}_{2}}\]
according to the reaction,
\[CaC{{O}_{3}}(s)+2HCl(aq)\to
\]
\[CaC{{l}_{2}}(aq)+C{{O}_{2}}(g)+{{H}_{2}}O(l)\]
What mass of \[CaC{{O}_{3}}\] is required to react completely
with 25 mL of 0.7 5 M HCl?
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Chlorine is prepared in the
laboratory by treating manganese dioxide (\[Mn{{O}_{2}}\]) with aqueous
hydrochloric acid according to the reaction:
\[4HCl(aq)+Mn{{O}_{2}}(s)\to MnC{{l}_{2}}(aq)\]
\[+2{{H}_{2}}O(l)+C{{l}_{2}}(g)\]
How many gram of HCl react with 5g of manganese dioxide?
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question_answer45)
In the following
questions only one option is correct.
Two students
performed the same experiment separately and each one of them recorded two
readings of mass which are given below. Correct reading of mass is 3.0 g. On
the basis of given data, mark the correct option out of the following
statements:
|
Student
|
Readings
|
|
|
|
(i)
|
(ii)
|
|
A
|
3.01
|
2.99
|
|
B
|
3.05
|
2.95
|
(a) Results of both
the students are neither accurate nor precise.
(b) Results
of student A are both precise and accurate.
(c) Results
of student B are neither precise nor accurate.
(d) Results
of student B are both precise and accurate.
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question_answer46)
A measured
temperature on Fahrenheit scale is \[{{200}^{{}^\circ }}F\]. What will this
reading be on Celsius scale?
(a) \[40{}^\circ
C\] (b) \[94{}^\circ C\]
(c) \[~93.3{}^\circ
C~~~~~~~~~~~~~~~~\] (d) \[30{}^\circ C\]
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question_answer47)
What will be
the molarity of a solution, which contains 5.85 g of \[NaCl(s)\] per 500 mL?
(a) \[4mol{{L}^{-1}}\]
(b) \[20\,mol\,{{L}^{-1}}\]
(c)
0 (d) \[2\,mol\,{{L}^{-1}}\]
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question_answer48)
If 500 mL of
a 5 M solution is diluted to 1500 mL, what will be the molarity of the solution
obtained?
(a) 1.5 M
(b) 1.66 M
(c) 0.017
M (d) 1.59 M
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question_answer49)
The number
of atoms present in one mole of an element is equal to Avogadro number. Which
of the following elements contains the greatest number of atoms?
(a) 4 g
He (b) 46 g Na
(c) 0.40 g Ca
(d) 12 g He
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question_answer50)
If the concentration
of glucose (\[{{C}_{6}}{{H}_{12}}{{O}_{6}}\]) in blood is 0.9 g \[{{L}^{-1}}\],
what will be the molarity of glucose in blood?
(a) 5
M (b) 50 M
(c) 0.005
M (d) 0.5 M
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question_answer51)
What will be
the molality of the solution containing 18.25 g of HCl gas in 500 g of water?
(a) 0.1 m
(b) 1 M
(c) 0.5 m
(d) 1 m
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question_answer52)
One mole of
any substance contains \[6.022\times {{10}^{23}}\] atoms/molecules. Number of
molecules of present in 100 mL of 0.02 M \[{{H}_{2}}S{{O}_{4}}\] solution is :
(a) \[12.044\times
{{10}^{20}}\] molecules
(b) \[6.022\times
{{10}^{23}}\] molecules
(c) \[1\times
{{10}^{23}}\] molecules
(d) \[12.044\times
{{10}^{23}}\] molecules
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question_answer53)
What is the
mass per cent of carbon in carbon dioxide?
(a)
0.034% (b) 27.27%
(c) 3.4%
(d) 28.7%
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question_answer54)
The
empirical formula and molecular mass of a compound are \[C{{H}_{2}}O\] and 180
g respectively. What will be the molecular formula of the compound?
(a) \[{{C}_{9}}{{H}_{18}}{{O}_{9}}\]
(b) \[C{{H}_{2}}O\]
(c) \[{{C}_{6}}{{H}_{12}}{{O}_{6}}\]
(d) \[{{C}_{6}}{{H}_{4}}{{O}_{2}}\]
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question_answer55)
If the density
of a solution is \[3.12m{{L}^{-1}}\], the mass of 1.5 mL solution in
significant figures is:
(a) 4.7 g
(b) \[4680\times {{10}^{-3}}g\]
(c) 4.680
g (d) 46.80 g
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question_answer56)
Which of the
following statements about a compound is incorrect?
(a) A
molecule of a compound has atoms of different elements.
(b) A
compound cannot be separated into its constituent elements by physical methods
of separation.
(c) A
compound retains the physical properties of its constituent elements.
(d) The
ratio of atoms of different elements in a compound is fixed.
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question_answer57)
Which of the
following statements is correct about the reaction given below :
\[4Fe(s)+3{{O}_{2}}(g)\to 2F{{e}_{2}}{{O}_{3}}(g)\]
(a) Total
mass of iron and oxygen in reactants = total mass of iron and oxygen in product
therefore it follows law of conservation of mass.
(b) Total
mass of reactants = total mass of product; therefore, law of multiple
proportions is followed.
(c) Amount
of \[F{{e}_{2}}{{O}_{3}}\] can be increased by taking any one of the reactants
(iron or oxygen) in excess.
(d) Amount
of \[F{{e}_{2}}{{O}_{3}}\] produced will decrease if the amount of any one of
the reactants (iron or oxygen) is taken in excess.
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question_answer58)
Which of the
following reactions is not correct according to the law of conservation of
mass?
(a) \[2Mg(s)+{{O}_{2}}(g)\xrightarrow{{}}2MgO(s)\]
(b) \[{{C}_{3}}{{H}_{8}}(g)+{{O}_{2}}(g)\xrightarrow{{}}C{{O}_{2}}(g)+{{H}_{2}}O(g)\]
(c) \[{{P}_{4}}(s)+5{{O}_{2}}(g)\xrightarrow{{}}{{P}_{4}}{{O}_{10}}(s)\]
(d) \[C{{H}_{4}}(g)+2{{O}_{2}}(g)\xrightarrow{{}}C{{O}_{2}}(g)+2{{H}_{2}}O(g)\]
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question_answer59)
Which of the
following statements indicates that law of multiple proportion is being followed?
(a) Sample
of carbon dioxide taken from any source will always have carbon and oxygen in
the ratio 1 : 2.
(b) Carbon
forms two oxides namely \[C{{O}_{2}}\] and\[CO\], where masses of oxygen which
combine with fixed mass of carbon are in the simple ratio 2 : 1.
(c) When
magnesium bums in oxygen, the amount of magnesium taken for the reaction is
equal to the amount of magnesium in magnesium oxide formed.
(d) At constant
temperature and pressure 200 mL of hydrogen will combine with 100 mL oxygen to
produce 200 mL of water vapour.
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question_answer60)
One mole of oxygen
gas at STP is equal to:
(a) \[6.022\times
{{10}^{23}}\] molecules of oxygen
(b) \[6.022\times
{{10}^{23}}\] atoms of oxygen
(c) 16 g of
oxygen
(d) 32 g of
oxygen
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question_answer61)
Sulphuric
acid reacts with sodium hydroxide as follows :
\[{{H}_{2}}S{{O}_{4}}+2NaOH\to
N{{a}_{2}}S{{O}_{4}}+2{{H}_{2}}O\]
When 1 L of
0.1 M sulphuric acid solution is allowed to react with 1 L of 0.1 M sodium
hydroxide solution, the amount of sodium sulphate formed and its molarity in
the solution obtained is:
(a) \[0.1mol{{L}^{-1}}\]
(b) 7.10 g
(c) \[0.025mol{{L}^{-1}}\]
(d) 3.55 g
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question_answer62)
Which of the
following pairs have the same number of atoms?
(a) \[16g\]of
\[{{O}_{2}}(g)\]and \[4\,g\]of \[{{H}_{2}}(g)\]
(b) \[16g\]of
\[{{\text{O}}_{2}}\]and \[44\,g\]of \[C{{O}_{2}}\]
(c) 28 g of \[{{N}_{2}}\]
and 32 g of \[{{O}_{2}}\]
(d) 12 g of C(s)
and 23 g of Na(s)
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question_answer63)
Which of the
following solutions have the same concentration?
(a) 20 g of \[NaOH\]
in 200 mL of solution
(b) 0.5 mol
of in 200 mL of solution
(c) 40 g of\[NaOH\]
in 100 mL of solution
(d) 20 g of \[KOH\]
in 200 mL of solution
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question_answer64)
16 g of
oxygen has same number of molecules as in :
(a) 16 g of \[CO\]
(b) 28 g of \[{{N}_{2}}\]
(c) 14 g of \[{{N}_{2}}\]
(d) 1.0 g of \[{{H}_{2}}\]
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question_answer65)
Which of the
following terms are unitless?
(a) Molality
(b) Molarity
(c) Mole
fraction (d) Mass per cent
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question_answer66)
One of the
statements of Dalton's atomic theory is given below:
"Compounds
are formed when atoms of different elements combine in a fixed ratio.
Which of the
following laws is not related to this statement?
(a) Law of
conservation of mass
(b) Law of
definite proportions
(c) Law of
multiple proportions
(d) Avogadro
law
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question_answer67)
What will be the
mass of one atom of C-12 in grams?
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question_answer68)
How many significant
figures should be present in the answer of the following calculation?
\[\frac{2.5\times
1,25\times 3.5}{2.01}\]
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question_answer69)
What is the symbol
for SI unit of mole? How is the mole defined?
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question_answer70)
What is the
difference between molality and molarity?
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question_answer71)
Calculate
the mass per cent of calcium, phosphorus and oxygen in calcium phosphate \[C{{a}_{3}}{{(P{{O}_{4}})}_{2}}.\]
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question_answer72)
45.4 L of dinitrogen
reacted with 22.7 L of dioxygen and 45.4 L of nitrous oxide was formed. The
reaction is given below :
\[2{{N}_{2}}(g)+{{O}_{2}}(g)\to
2{{N}_{2}}\text{O}(g)\]
Which law is being
obeyed in this experiment? Write the statement of the law.
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question_answer73)
If two elements can
combine to form more than one compound, the masses of one element that combine
with a fixed mass of the other element, are in whole number ratio.
(a) Is this
statement true?
(b) If yes,
according to which law?
(c) Give one
example related to this law.
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question_answer74)
Calculate the
average atomic mass of hydrogen using the following data :
|
Isotope
|
% Natural abundance
|
Molar mass
|
|
\[^{1}H\]
|
99.985
|
1
|
|
\[^{2}H\]
|
0.015
|
2
|
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question_answer75)
Hydrogen gas is
prepared in the laboratory by reacting dilute HCl with granulated zinc.
Following reaction takes place :
\[Zn+2HCl\to ZnC{{l}_{2}}+{{H}_{2}}\]
Calculate
the volume of hydrogen gas liberated at STP, when 32.65 g of zinc reacts with
HCl. 1 mol of a gas occupies 22.7 L volume at STP; atomic mass of \[Zn=65.3\,u\].
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question_answer76)
The density
of 3 molal solution of \[NaOH\] is \[1.110\,g\,m{{L}^{-1}}\].Calculate the
molarity of the solution.
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question_answer77)
Volume of a
solution changes with change in temperature then, will the molality of the
solution be affected by temperature? Give reason for your answer.
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question_answer78)
If 4 g of \[NaOH\]
dissolves in 36 g of \[{{H}_{2}}O\] calculate the mole fraction of each
component in the solution. Also, determine the molarity of solution (specific
gravity of solution is 1g\[m{{L}^{-1}}\]).
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question_answer79)
The reactant
which is entirely consumed in reaction is known as limiting reagent.
In the
reaction \[2A+4B\to 3C+4D\], when 5 moles of A react with 6 moles of B, then :
(a) which is
the limiting reagent?
(b) calculate
the amount of C formed.
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question_answer80)
Match the following
:
|
(i) \[88\,g\,of\,C{{O}_{2}}\]
|
(a) \[0.25\,mol\]
|
|
(ii) \[6.022\times
{{10}^{23}}\]
Molecules of \[{{H}_{2}}O\]
|
(b) \[2\,mol\]
|
|
(iii) 5.6 litres of \[{{O}_{2}}\] at STP
|
(c) 1 mol
|
|
(iv) \[96\,g\]of \[{{O}_{2}}\]
|
(d) \[6.022\times {{10}^{23}}\]molecules
|
|
(v) \[1\,mol\]of any gas
|
(e) \[3\,mol\]
|
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question_answer81)
Match the following
physical quantities with units :
|
Physical quantity
|
Unit
|
|
(i) Molarity
|
(a) \[g\,m{{L}^{-1}}\]
|
|
(ii) Mole fraction
|
(b) mol
|
|
(iii) Mole
|
(c) pascal
|
|
(iv) Molality
|
(d) Unitless
|
|
(v) Pressure
|
(e) mol \[{{L}^{-1}}\]
|
|
(vi) Luminous intensity
|
(f) candela
|
|
(vii) Density
|
(g) mol \[k{{g}^{-1}}\]
|
|
(viii)Mass
|
(h) \[N\,\,{{m}^{-1}}\]
|
|
|
(i) kg
|
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question_answer82)
In the following
questions a statement of Assertion (A) followed by a statement of Reason (R) is
given. Choose the correct option out of the choices given below each question.
Assertion
(A): The empirical mass of ethene is half of its molecular mass.
Reason (R):
The empirical formula represents the simplest whole number ratio of various
atoms present in a compound.
(a) Both A
and R are true and R is the correct explanation of a.
(b) A is
true but R is false.
(c) A is
false but R is true.
(d) Both A
and R are false.
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question_answer83)
Assertion (A):
One atomic mass unit is defined as one twelfth of the mass of one carbon-12
atom.
Reason (R):
Carbon-12 isotope is the most abundant isotope of carbon and has been chosen as
standard.
(a) Both A
and R are true and R is the correct explanation of A.
(b)Both A
and R are true but R is not the correct explanation of A.
(c) A is
true but R is false.
(d) Both A
and R are false.
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question_answer84)
Assertion
(A): Significant figures for 0.200 is 3 whereas for 200 it is 1.
Reason (R):
Zero at the end or right of a number are significant provided they are not on
the right side of the decimal point.
(a) Both A
and R are true and R is the correct explanation of A.
(b)Both A
and R are true but R is not the correct explanation of A.
(c) A is
true but R is false.
(d) Both A
and R are false.
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question_answer85)
Assertion
(A): Combustion of 16 g of methane gives 18 g of water.
Reason (R):
In the combustion of methane, water is one of the products.
(a) Both A
and R are true but R is not the correct explanation of A.
(b) A is
true but R is false.
(c) A is
false but R is true.
(d) Both A
and R are false.
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question_answer86)
A vessel contains
1.6 g of dioxygen at STP (273.15 K. 1 atm pressure). The gas is now transferred
to another vessel at constant temperature, where pressure becomes half of the
original pressure. Calculate :
(a) volume
of the new vessel.
(b) number
of molecules of dioxygen.
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question_answer87)
Calcium
carbonate reacts with aqueous HCl to give \[CaC{{l}_{2}}\] and \[C{{O}_{2}}\]
according to the reaction given below :
\[CaC{{O}_{3}}(s)+2HCl(aq)\xrightarrow[{}]{{}}CaC{{l}_{2}}(aq)\]\[+C{{O}_{2}}(g)+{{H}_{2}}O(l)\]
What mass of
\[CaC{{l}_{2}}\] will be formed when 250 mL of 0.76 M HCl reacts with 1000 g of
\[CaC{{O}_{3}}\]? Name the limiting reagent. Calculate the number of moles of \[CaC{{l}_{2}}\]
formed in the reaction.
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question_answer88)
Define the
law of multiple proportions. Explain it with two examples. How does this law
point to the existence of atoms?
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question_answer89)
A box
contains some identical red coloured balls, labelled as A, each weighing 2
grams. Another box contains identical blue coloured balls, labelled as B, each
weighing 5 grams.
Consider the
combinations AB, \[A{{B}_{2}}\], \[{{A}_{2}}B\]and \[{{A}_{2}}{{B}_{3}}\] and show
that law of multiple proportions is applicable.
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