Basic concepts
NoQuestionsHelp
1The percentage of oxygen in NaOH is( )40
( )10
( )8
( )60
Single Answer
2What quantity of limestone (CaCO3) on heating will give 56 kg of CaO( )1000 kg
( )44 kg
( )100 kg
( )56 kg
Single Answer
3Which of the following has least mass( )3 x 10^23 atoms of C
( )7.0 g of Ag
( )1 mole of S
( )2 gram atom of nitrogen
Single Answer
41 mole of CH4 contains ( )3.0 g of carbon
( )1.81 x 10^23 molecules of CH4
( )6.02 x 10^23 atoms of H
( )4 g-atom of hydrogen
Single Answer
5How many moles of Helium gas occupy 22.4 L at 0 degree Celcius and 1 atm pressure( )0.90
( )1.0
( )0.11
( )1.11
Single Answer
6The number of atoms contained in 11.2 L of SO2 at S.T.P. are( )3/2 x 6.02 x 10^23
( )2 x 6.02 x 10^23
( )6.02 x 10^23
( )4 x 6.02 x 10^23
Single Answer
7The number of oxygen atoms in 4.4 g of CO2 is approximately( )6 x 10^23
( )1.2 x 10^23
( )12 x 10^23
( )6 x 10^23
Single Answer
8The total number of protons in 10 g of calcium carbonate is (No=6.023 x 10^23)( )1.5057 x 10^24
( )2.0478 x 10^24
( )3.0115 x 10^24
( )4.0956 x 10^24
Single Answer
92 g of oxygen contains number of atoms equal to that in( )7 g of nitrogen
( )0.5 g of hydrogen
( )2.3 g of sodium
( )4 g of sulphur
Single Answer
10If N(A) is avogadro's number, then number of valence electrons in 4.2 g of nitride ions N^3- is( )4.2 N(A)
( )1.6 N(A)
( )3.2 N(A)
( )2.4 N(A)
Single Answer
11The hydrogen phosphate of certain metal has formula MHPO4. The formula of metal chloride would be( )M2Cl2
( )MCl3
( )MCl2
( )MCl
Single Answer
12The number of atoms in 4.25 g of NH3 is approximately( )1 x 10^23
( )1.5 x 10^23
( )2 x 10^23
( )6 x 10^23
Single Answer
13The maximum amount of BaSO4 precipitate on mixing BaCl2 (0.5 M) with H2SO4 (1 M) will correspond to( )1.0 M
( )1.5 M
( )2.0 M
( )0.5 M
Single Answer
14The largest no. of molecules is in( )54 g of N2O5
( )46 g of CH3OH
( )28 g of CO2
( )34 g of water
Single Answer
15Assuming full decomposition the volume of CO2 released at STP on heating 9.85 g of BaCO3 (At. Mass Ba=197) will be( )1.12 L
( )0.84 L
( )4.06 L
( )0.24 L
Single Answer
16In a mole of water vapours ar STP the volume actually occupied or taken by the molecules (i.e. avogadro's no. x volume of one molecule) is( )Zero
( )1% to 2% of 22.4 L
( )About 10% of the volume of container
( )Less than 1% of 22.4 L
Single Answer
17Vapour density of a gas is 22. What is its molecular mass( )22
( )44
( )11
( )33
Single Answer
181.5 mol of O2 combine with Mg to form oxide MgO. The mass of Mg( at.mass 24) that has combined is( )72 g
( )36 g
( )24 g
( )48 g
Single Answer
19The volume of water to be added to 100 cm3 of 0.5 N H2SO4 to get concentrated is( )500 cm3
( )450 cm3
( )100 cm3
( )400 cm3
Single Answer
20Among the following pairs, the one which illustrates the law of multiple proportion is( )CuO, Cu2O
( )H2S, SO2
( )NH3, HCl
( )CS2, FeSO4
Single Answer
21The set of numerical coefficients that balances the chemical equation K2CrO4 + HCl------->K2Cr2O7 + KCl + H2O( )2,2,1,2,1
( )1,1,2,2,1
( )2,1,1,2,1
( )2,2,1,1,1
Single Answer
22The prefix 10^18 is( )Exa
( )Kilo
( )Giga
( )Nano
Single Answer
23Difference in density is the basis of( )Molecular attraction
( )Ultrafiltration
( )Gravity separation
( )Molecular sieving
Single Answer
24Irrespective of the source, pure sample of water always yields 88.89 % mass of oxygen and 11.11% mass of hydrogen. This is explained by the law of( )Multiple proportions
( )Definite proportions
( )Constant volume
( )Conservation of mass
Single Answer
25The weight of one molecule of a compound C60H122 is( )1.3 x 10^-20 g
( )3.72 x 10^23 g
( )5.01 x 10^-21 g
( )1.4 x 10^-21 g
Single Answer
26Number of atoms in 558.5 g of Fe (At.mass of Fe=55.85 g/mol) is( )Twice that in 60 g carbon
( )Half that in 8 g of He
( )558.5 x 6.022 x 10^23
( )6.022 x 10^22
Single Answer
27To differentiate between C-12, C-13 and C-14, the instrument that you would use is( )Ultravoilet spectrometer
( )Mass spectrometer
( )Infra-red spectrometer
( )Atomic absorption spectrometer
Single Answer
280.56 g of a gas occupies 280 cm3 at N.T.P, then its molecular mass is( )4.8
( )22.4
( )2
( )44.8
Single Answer
29Which one of the following is ambiguous( )A mole of potassium ions
( )A mole of electrons
( )A mole of sodium atoms
( )A mole of hydrogen
Single Answer
30X litres of carbon monoxide is present at S.T.P. It is completely oxidized to CO2. The volume of CO2 formed is 11.207 L at S.T.P. What is the value of X in litres( )22.414 L
( )11.207 L
( )5.6035 L
( )44.828 L
Single Answer
310.078 g of a hydrocarbon occupy 22.414 mL of volume at S.T.P. The empirical formula of the hydrocarbon is CH. The molecular formula of hydrocarbon is( )C6H6
( )C8H8
( )C4H4
( )C2H2
Single Answer
32In Haber process 30 L of dihydrogen and 30 L of dinitrogen were taken for reaction which yielded only 50% of the expected product. What will be the composition of gaseous mixture under the aforesaid conditions in the end( )20 L of ammonia, 20 L of nitrogen, 20 L of hydrogen
( )20 L of ammonia, 25 L of nitrogen, 15 L of hydrogen
( )10 L of ammonia, 25 L of nutrogen, 15 L of hydrogen
( )20 L of ammonia, 10 L of nitrogen, 30 L of hydrogen
Single Answer
33What volume of hydrogen gas at 273 K and 1 atm pressure will be consumed in obtaining 21.6 g of elemental boron (at.mass=10.8) from the reduction of boron trichloride by hydrogen( )67.2 L
( )89.6 L
( )22.4 L
( )44.8 L
Single Answer
34The equivalent weight of a certain trivalent element is 20. Molecular weight of its oxide is( )168
( )152
( )56
( )68
Single Answer
35There are two isotopes of an element with atomic mass z. Heavier one has atomic mass z+2 and lighter one has z-1, then abundance of lighter one is( )33.3%
( )96.7%
( )66.6%
( )6.67%
Single Answer
36In an acidic medium dichromate ion oxidizes ferrous ion to ferric ion. If the gram molecular mass of potassium dichromate is 294 g, its gram equivalent mass is ______grams( )49
( )294
( )24.5
( )127
Single Answer
37The empirical formula of a compound is CH2O and its molecular mass is 120. The molecular formula of the compound is( )C4H8O4
( )CH2O
( )C2H4O2
( )C3H6O3
Single Answer
382g of aluminium is treated, separately with excess of dilute H2SO4 and excess of NaOH the ratio of volumes of hydrogen evolved is( )1:2
( )1:1
( )2:1
( )2:3
Single Answer
39The numerical value of N/n (where N is the number of molecules in a given sample of gas and n is the number of moles of the gas) is( )8.314
( )6.02 x 10^23
( )1.66 x 10^-19
( )1.62 x 10^-24
Single Answer
40A sample of phosphorus trichloride (PCl3) contains 1.4 moles of the subtance. How many atoms are there in the sample?( )5.6
( )8.431 x 10^23
( )4
( )3.372 x 10^24
Single Answer
41A gaseous mixture contains 50% helium and 50% methane by volume. What is the percent by weight of methane in the mixture?( )80.03%
( )50%
( )10.05%
( )19.97%
Single Answer
42How will you separate a mixture of two gases( )Osmosis
( )Chromatography
( )Fractional distillation technique
( )Graham's law of diffusion technique
Single Answer
43What is the net charge on ferous ion( )+2
( )+5
( )+4
( )+3
Single Answer
446.0 x 10^20 molecules of urea are present in 100 mL of its solution. The concentration of urea solution is( )0.02 M
( )0.1 M
( )0.001 M
( )0.01 M
Single Answer
45Volume of 0.1 M K2Cr2O7 required to oxidise 35 mL of 0.5 M FeSO4 solution is ( )17.5 mL
( )175 mL
( )145 mL
( )29.2 mL
Single Answer
46For decolourizing 1 mole of KMnO4, in acidic medium the moles of H2O2 required is( )5/2
( )7/2
( )3/2
( )1/22KMnO4 + 5H2O2 + 3H2SO4 ---> 2MnSO4 + 5O2 + K2SO4 + 8H2O
Single Answer
474 g of copper was dissolved in conc.Nitric acid. The copper nitrate so obtained on strong heating gave 5 g of its oxide. The equivalent weight of copper is( )23
( )32
( )20
( )12
Single Answer
48In alkaline medium ClO2 oxidises H2O2 to O2 and itself gets reduced to Cl-. How many moles of H2O2 are oxidized by 1 mole ClO2( )1.5
( )1.0
( )3.5
( )2.5
Single Answer
49100 g of CaCO3 is treated with 1 L of 1 N HCl. What would be the weight of CO2 liberated after the completion of the raction( )33 g
( )11 g
( )22 g
( )5.5 g
Single Answer
50If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to be the realtive atomic mass unit, the mass of one mole of substance will( )Increase two fold
( )Decrease twice
( )Be a function of the molecular mass of substance
( )Remains unchanged
Single Answer
51If 30 mL of H2 and 20 mL of O2 reacts to form water, what is left at the end of the reaction( )10 mL of O2
( )10 mL of H2
( )5 mL of O2
( )5 mL of H2
Single Answer
52An alkaloid contains 17.28 % of nitrogen and its molecular mass is 162. The number of nitrogen atoms present in one molecule of alkaloid is( )Three
( )Two
( )Four
( )Five
Single Answer
53'x' grams of calcium carbonate was completely burnt in air. The weight of the solid residue formed is 28 g. What is the value of 'x' in grams( )150
( )50
( )44
( )200
Single Answer
54What is the concentration of nitrate ions, if equal volumes of 0.1 M AgNO3 and 0.1 M NaCl are mixed together( )0.1 M
( )0.25 M
( )0.2 M
( )0.05 M
Single Answer
55A solution of 10 mL of M/10 FeSO4 was titrated with KMnO4 solution in acidic medium, the amount of KMnO4 used will be( )10 mL of 0.5 M
( )5 mL of 0.1 M
( )10 mL of 0.1 M
( )10 mL of 0.02 M
Single Answer
56The volume in litres of CO2 liberated at STP when 10 grams of 90% pure limestone is heated completely is( )2.24
( )20.16
( )22.4
( )2.016
Single Answer
57An organic compound contains 49.3% carbon, 6.84% hydrogen and its vapour density is 73. Molecular formula of compound is( )C4H10O2
( )C3H5O2
( )C3H10O2
( )C6H10O4
Single Answer
58"A piece of iron was placed in a china dish. After a month Dr.Khan found it rusted. He thought that air must be responsible for rusting of iron." This statement is consist of( )Observation and conclusion
( )Observation and hypothesis
( )Idea and data
( )Idea and hypothesis
Single Answer
59During chemical analysis of a compound containing carbon, hydrogen and oxygen, H2O produced is absorbed by( )NaOH
( )Mg(OH)2
( )Mg(ClO4)2
( )CaCO3
Single Answer
60Which of the following represents 1 mol of the substance( )6.022 x 10^24 molecules of NH3
( )4 g of helium
( )40 g calcium chloride
( )6.022 x 10^-24 molecules of CO2
Single Answer
61Urea (NH2)2CO is used as fertilizer. If 2 moles of urea are present in a container than mass of nitrogen in the compound will be( )14 g
( )28 g
( )56 g
( )42 g
Single Answer
628 g of methane contains( )4 x 6.022 x 10^23 hydrogen atoms
( )4 hydrogen atoms
( )6.022 x 10^23 carbon atoms
( )0.5 mol of carbon atoms
Single Answer
63A beaker has 180 g of water in it. Number of moles of oxygen atoms in it will be( )18
( )10
( )180
( )20
Single Answer
6423.5 g of N2 contain as much atoms as in( )23.5 g of Cl2
( )23.5 g of H2
( )23.5 g of CO
( )23.5 g of O2
Single Answer
65Sample containing maximum number of atoms among the following is( )6 g of He
( )28 g N2
( )4 g H2
( )48 of O2
Single Answer
66An unknown compound was analyzed. The result relealed that it contain 80% carbon and 20% hydrogen. On the basis of the available data, empirical formula of the compound must be( )CH
( )CH2
( )C2H5
( )CH3
Single Answer
67All of the following compounds can be analyzed by combustion analysis except( )C12H22O11
( )C6H6
( )H2O2
( )C2H2
Single Answer
68If a piece of 4 mol of lithium is dropped in 72 g of water in a container then( )2 mol of water is left unreacted
( )2.5 mol of lithium is left unreacted
( )2 mol of lithium is left unreacted
( )None of the reactants is left unreacted
Single Answer
69If sulphur is in excess then production of 2 mol of ferrous sulfide requires( )4 mol of iron
( )56 g of iron
( )2 mol of iron
( )28 g of iron
Single Answer
70If theoritical and percentage yields of a product are 50 g and 90 g respectively, then actual yield of the product will be( )70 g
( )80 g
( )45 g
( )35 g
Single Answer
71All of the following may not be the average atomic masses except( )30.03
( )32
( )12
( )2
Single Answer
72Dr.Khan has discovered two isotopes of an element with atomic number 119. The relative abundance of isotopes 119Uue300 and 119Uee305 is 70% and 30% respectively. The average atomic mass of Uue is( )301.5 a.m.u
( )303.5 a.m.u
( )302.5 a.m.u
( )304.5 a.m.u
Single Answer
73DDT is widely used as an isecticide. Its molar mass is 354.5 g/mol. When DDT was analyzed by a chemist he found that it contains 47.4% carbon. How many carbon atoms are there in each DDT molecule( )10
( )14
( )12
( )16
Single Answer
74The mass of 2 moles of sodium hydroxide will be( )20 g
( )2 g
( )80 g
( )40 g
Single Answer
75A compound contains two elements X and Y. Percentage of X is 20% (At.wt=40) and that of Y is 80% (At.wt=80). The empirical formula of the compound is( )XY2
( )X3Y
( )XY
( )X2Y
Single Answer
76A piece of paper is burnt in air, the gas produced is passed through distilled water. The pH of water solution will be( )1
( )2.1
( )7
( )6.7
Single Answer
77Ozone filters the cosmic rays if sunlight. How many oxygen atoms are there in 0.2 mol of ozone (O3 molar mass=48.0g/mol)( )6.02 x 10^22
( )3.61 x 10^23
( )6.02 x 10^23
( )6 x 10^23
Single Answer
78FeSO4.xH2O loses its water of crystallization upon heating. In an experiment 2.1 mole of water is obtained by heating 0.3 mole of the hydrated salt. Chemical formula of FeSO4.xH2O is( )FeSO4.6H2O
( )FeSO4.7H2O
( )FeSO4.8H2O
( )FeSO4.5H2O
Single Answer
79Tobacco contains a poisonous alkaloid called Nicotine. The molecular formula of nicotine is C10H14N2 (molar mass=162.23 g). The mass percentage of nitrogen in nicotine is?( )17.3%
( )12.4%
( )4.32%
( )8.23%
Single Answer
80A sample of an ionic compound contains 2.82 g Na, 4.35 g Cl and 7.83 g O. The empirical formula of this compound is( )NaClO4
( )NaClO2
( )NaClO3
( )NaClO
Single Answer
81Verbal or mathematical relationship between phenomenon is called( )Observation
( )Law
( )Conclusion
( )Data
Single Answer
82The statement that "the composition of a particular compound always remains constant" is a( )Law
( )Hypothesis
( )Fact
( )Theory
Single Answer
83"Solid potassium bromide was mixed with solid silver nitrate". The expectation of a chemist will be( )Silver bromide will be produced
( )Potassium nitrate and silver bromide will be produced
( )No chemical reaction will occur
( )Potassium nitrate will be produced
Single Answer
84All of the following are pure substances except( )Diamond
( )Alumina
( )Graphite
( )Sea water
Single Answer
85All of the following are not pure substances except( )Hard water
( )Tap water
( )Heavy water
( )Rain water
Single Answer
86All of the following are not molecule except( )H2O2
( )CaCl2
( )Na2O2
( )Al(NO3)3
Single Answer
87Which of the following is not related to a.m.u?( )Kilogram
( )Microgram
( )Gram/lit
( )Gram
Single Answer
88Copper(II) oxide is mixed with organic compound during combustion analysis. The purpose is( )To carry out complete combustion
( )To reduce the economy of the process
( )To reduce the time for completion of the reaction
( )All of the above
Single Answer
89The following statement contained in a student's laboratory report is a conclusion.( )The gas is chlorine
( )Color of the gas is greenish yellow
( )Oxide of the gas is strongly acidic
( )A gas is liberated
Single Answer
90One a.m.u is equal to( )1.661 x 10^-24 kg
( )1.661 x 10^-24 mg
( )1.661 x 10^-27 kg
( )1.661 x 10^-27 g
Single Answer
91Objects of the size of an atom can be observed in( )An x-ray spectrum
( )Atomic absorption spectrum
( )An electron microscope
( )A visible spectrum
Single Answer
92Which one of the following statements is not correct( )He is a molecule of helium
( )S8 is a molecule of sulphur
( )O3 is a molecule of oxygen
( )A molecule is the smallest particle of an element which can exist independently
Single Answer
93A molecule of hemoglobin is made up of nearly( )10,000 atoms
( )1500 atoms
( )2500 atoms
( )50,000 atoms
Single Answer
94Which of the following statement is correct. For a chemical reaction to occur molecules of substances must( )Collide with high frequency
( )Collide with energy more than activation energy
( )Collide with each other
( )Collide with energy less than activation enegy
Single Answer
95Al^3+ is a symbol for aluminium( )Atom
( )Cation
( )Anion
( )Ion
Single Answer
96Cr2O7^2- is a( )A complex anion
( )Double salt
( )A carbocation
( )A complex ion
Single Answer
97A molecular ion is formed by( )Passing electric current through molten salt
( )Dissolving a salt in dilute acid
( )Passing electricity through aqeous solutions
( )Passing a high energy electron beam through gaseous molecule
Single Answer
98Mass spectrometer mesures( )Exact mass of an element
( )Average mass of an element
( )The number of elements present in a molecule
( )M/e value of a positive ion
Single Answer
99Percentage of H is highest in( )NH3
( )CH4
( )C6H12O6
( )H2SO4
Single Answer
100Ascorbic acid contains 40.92% carbon, 4.58 % hydrogen and 54.5 % oxygen. The empirical formula is( )C2H4O3
( )C2H3O1
( )C3H4O3
( )C3H5O4
Single Answer
101The relative abundance of Pb isotopes is 1.5% Pb 204, 23.6% Pb 206, 22.6% Pb 207, 52.3% Pb 208. The relative atomic mass of Pb is( )206.94
( )207.94
( )207.24
( )208.24
Single Answer
102The pressure of vapours when sent to the ionization chamber in mass spectrometer is( )10^-6 to 10^-7 torr
( )10^-5 to 10^-6 torr
( )10^-3 to 10^-4 torr
( )10^-7 to 10^-8 torr
Single Answer
103The relative abundance of the ions with a definite m/e value is measured by( )Quantity of fast moving electrons
( )High pressure of vapours
( )Strength of electric current measured
( )Electron gas
Single Answer
104Which of the following statements is not true( )Isotopes with even atomic masses are comparatively abundant
( )Isotopes with even atomic masses and odd atomic numbers are comparitively abundant
( )Isotopes with even atomic masses and even atomic number are comparatively abundant
( )Isotopes with odd atomic masses are comparatively abundant
Single Answer
105Which of the following compounds contains the highest percentage by mass of nitrogen( )Ammonium carbonate, (NH4)2CO3
( )Ammonia, NH3
( )Hydrazine, N2H4
( )Ammonium carbamate, NH2CO2NH4
Single Answer
106Which one of the following compounds does not have the empirical formula CH2O( )Glucose, C6H12O6
( )Mthanal, HCHO
( )Ethanoic acid, CH3CO2H
( )Ethanol, CH3CH2OH
Single Answer
107The empirical formula of a liquid compound is known to be C2H4O. What other information is needed to work out its molecular formula( )The relative molecular mass of the compound
( )The volume occupied by one mole of the compound
( )The density of the compound
( )The percentage composition of the compound
Single Answer
108H2O produced during combustion of an organic compound is absorbed in( )Mg(ClO4)2
( )50% KOH
( )Conc.H2SO4
( )Al2O3
Single Answer
109The percentage of which element in the organic compound is determined by the difference method( )Carbon
( )Hydrogen
( )Nitrogen
( )Oxygen
Single Answer
110A compound contains one atom of oxygen and % of O 34.78, then molecular mass of the compound is( )46
( )78
( )180
( )110
Single Answer
111A compound having empirical formula C3H3O and its molecular mass is 110.02. Its molecular formula is( )C6H6O2
( )C9H9O3
( )C3H3O
( )C3H6O2
Single Answer
112Which has greater number of moles( )6.02 x 10^20 atoms of magnesium
( )20 cm3 0.1 mole per dm3 of NaOH
( )0.1 g sodium
( )12.2 dm3 of nitrogen at standard, temperature and pressure [Ar Na=23, Mg=24, O=16]
Single Answer
113One mole of ethanol and one mole of ethane have an equal( )Number of molecules
( )Number of electrons
( )Mass
( )Number of atoms
Single Answer
114A compound X contains 50% sulphur and 50% oxygen by mass. What is the empirical (simplest) formula of compound X( )SO
( )SO2
( )SO3
( )SO4
Single Answer
115Two different hydrocarbon each contain the same percentage by mass of hydrogen. It follows that they have the same( )Relative molecular mass
( )Number of atoms in a molecules
( )Number of isomers
( )Empirical formula
Single Answer
116A compound contains 75% carbon and 25% hydrogen, by mass. What is the molecular formula of the compound( )C3H8
( )CH4
( )C2H4
( )C2H6
Single Answer
117How many moles of hydrogen atoms does 3.2 g of methane, CH4 contain( )0.4
( )0.8
( )0.02
( )0.2
Single Answer
118A balloon contains 0.02 g of He gas, it contains He molecules( )3.01 x 10^22
( )6.02 x 10^23
( )6.02 x 10^21
( )3.01 x 10^21
Single Answer
119One mole of C2H5OH contains the number of H-atoms( )6.02 x 10^23
( )6.02 x 10^24
( )3.61 x 10^24
( )1.81 x 10^24
Single Answer
120A ring contains 3 grams diamond. The number of C-atoms which a ring contains is( )3.01 x 10^24
( )3.01 x 10^23
( )1.5 x 10^23
( )6.02 x 10^24
Single Answer
121When nitrogen is 5.6 grams in NO2, then number of moles of NO2 is( )0.05
( )0.5
( )0.04
( )0.4
Single Answer
1223.01 x 10^22 Ag^+ ions is present in( )8.5 g AgNO3
( )85 grams AgNO3
( )0.85 g AgNO3
( )18.5 g AgNO3
Single Answer
123One mole of SO2 contains( )6.02 x 10^23 atoms of sulphur
( )4 gram atoms of SO2
( )6.02 x 10^23 atoms of oxygen
( )18.1 x 10^23 molecules of SO2
Single Answer
124The largest number molecules are present in( )2.8 g of CO
( )4.8 g of C2H5OH
( )3.6 g of H2O
( )5.4 g of N2O5
Single Answer
125The mass of one mole of proton is( )1.008 mg
( )1.008 g
( )1.673 g
( )0.184 g
Single Answer
12610 cm3 of Cl2 gas at STP has molecules( )1.003 x 10^22
( )1.003 x 10^23
( )2.7 x 10^20
( )2.7 x 10^21
Single Answer
1274.6 grams of C2H5OH and 6 grams of C2H6 have( )C2H5OH has greater number of molecules
( )C2H6 has greater number of molecules
( )Equal number of molecules
( )C2H6 has less mass of carbon
Single Answer
128The volume occupied by 1.4 g of N2 at STP is( )1.12 dm3
( )112 cm3
( )22.4 dm3
( )2.24 dm3
Single Answer
129A limiting reactant is the one which( )Gives the maximum amount of the product which is required
( )Is taken in lesser quatity in grams as compared to other reactants
( )Gives the minimum amount of the product under consideration
( )Is taken in lesser quantity in volume as compared to the other reactants
Single Answer
130When one mole ofeach of the following is completely burned in oxygen, which gives the largest mass of carbon dioxide( )Carbon monoxide
( )Diamond
( )Methane
( )Ethane
Single Answer
131Methane reacts with steam to form hydrogen and carbon monoxide as CH4 + H2O------>3H2 + CO. What volume of hydrogen can be obtained from 100 cm3 of methane (at the same temperature and pressure)( )300 cm3
( )100 cm3
( )150 cm3
( )200 cm3
Single Answer
132Hydrogen reacts with oxygen as s 2H2(g) + O2(g)-------->2H2O(l). How much gas will remain if 2 dm3 of hydrogen are reacted with 1 dm3 of oxygen at room temperature( )0
( )3 dm3
( )2 dm3
( )3 cm3
Single Answer
133How many moles of oxygen, O2 are needed for the complete combustion of two moles of butane, C4H10( )13
( )8
( )10
( )2
Single Answer
134Wha tis the maximum mass of aluminium which can be obtained from 240 g of aluminium oxide, Al2O3?( )26 g
( )108 g
( )51 g
( )127 g
Single Answer
135If four moles of sulphur dioxide are oxidized to sulphur trioxide, how many moles of oxygen molecules are required( )2.0
( )1.0
( )0.5
( )1.5
Single Answer
136When 0.1 g of magnesium is treated with an excess of hydrofluoric acid, what volume of gas at room temperature and pressure will be produced( )25 cm3
( )48 cm3
( )100 cm3
( )10 cm3
Single Answer
137Quicklime (calcium oxide) is manufactured by heating limestone (calcium carbonate) CaCO3-------->CaO + CO2, What mass of quicklime can be produced by heating one kg of limestone( )56/100 kg
( )28/204 kg
( )28/100 kg
( )56/124 kg
Single Answer
138The mass of sulphur which combines with 24 grams oxygen to form SO2( )24 grams
( )8 grams
( )12 grams
( )32 grams
Single Answer
139The mass of Al2S3 formed when 20 grams Al reacts completely with S is( )55.55 g
( )60 g
( )50.55 g
( )50 g
Single Answer
140Ethanol burns in O2 completely accoding to reaction C2H5OH + 3 O2---------->2CO2 + 3H2O. The mass of O2 needed to burn 0.1 mole of C2H5OH is( )3.2 g
( )32 g
( )5.6 g
( )9.6 g
Single Answer
1411.12 dm3 of N2 gas at STP has mass of N2 gas( )2.4 g
( )14 g
( )1.4 g
( )2.8 g
Single Answer
142A beaker contains 9 grams of water. The number of hydrogen atoms is( )6.02 x 10^24
( )6.02 x 10^23
( )3.01 x 10^23
( )3.01 x 10^24
Single Answer
143A reactant will be limiting reactant if it gives( )Gives zero moles of the product
( )Least number of moles of the product
( )Which gives reversible reaction
( )Highest number of moles of the product
Single Answer
144In the reaction 2N2H4 + N2O4--------->3N2 + 4H2O; 100 grams of each reactant is combined together, then( )N2O4 is limiting reactant
( )Reactants are completely converted to the products
( )Reaction is reversible
( )N2H4 is limiting reactant
Single Answer
1450.5 mole of CH4 and 0.5 mole of SO2 gases have equal( )Mass in grams
( )Volume
( )Number of molecules
( )Total number of atoms
Single Answer
146In reaction CH4 + 2O2--------->CO2 + 2H2O; 8 grams of complete burning of CH4 gives 18 grams CO2. The percentage yield is( )89.89%
( )81.81%
( )90.90%
( )84.84%
Single Answer
147When CaCO3 is heated it decomposes according to equation CaCO3(s)----------->CaO(s) + CO2(g). When 4.5 Kg CaCO3 is heated 2.5 Kg CaO is formed. The percentage yield is( )99.2%
( )90.5%
( )96.2%
( )99.5%
Single Answer
148The number of moles of CO2 which contain 8.0 g of oxygen( )0.25
( )1.0
( )0.50
( )1.50
Single Answer
149Mass of oxygen needed to react with 27 g aluminium to form Al2O3 according to the equation 2Al + 3/2 O2-------->Al2O3 is( )32 g
( )16 g
( )24 g
( )8 g
Single Answer
150The phenomenon of isotopy was first discovered by( )Rutherford
( )Bohr
( )Dalton
( )Soddy
Single Answer
151The atomic mass of an element is expressed in( )Kilograms
( )Ounce
( )Grams
( )A.m.u
Single Answer
152When NH3 gas reacts with HCl white fumes are formed which are chemically( )HCl fumes
( )Cl-
( )NH4^+
( )NH4Cl
Single Answer
153When carbon dioxide passes through lime water, Ca(OH)2 aqueous solution, white precipitate is formed. It is( )CaO
( )CaCO3
( )H2CO3
( )Ca2CO3
Single Answer
Top Related