11242 + Mcqs in Chemistry Page 85 McqOptions

4201.	The percentage of copper and oxygen in samples of \[CuO\] obtained by different methods were found to be the same. This illustrates the law of [AMU 1982, 92]
A.	Constant proportions
B.	Conservation of mass
C.	Multiple proportions
D.	Reciprocal proportions
Answer» B. Conservation of mass

Discussion

4202.	Among the following pairs of compounds, the one that illustrates the law of multiple proportions is
A.	\[N{{H}_{3}}\text{ and }NC{{l}_{3}}\]
B.	\[{{H}_{2}}S\text{ and }S{{O}_{2}}\]
C.	\[CuO\text{ and C}{{\text{u}}_{\text{2}}}O\]
D.	\[C{{S}_{2}}\text{ and }FeS{{O}_{4}}\]
Answer» D. \[C{{S}_{2}}\text{ and }FeS{{O}_{4}}\]

Discussion

4203.	The law of definite proportions is not applicable to nitrogen oxide because [EAMCET 1981]
A.	Nitrogen atomic weight is not constant
B.	Nitrogen molecular weight is variable
C.	Nitrogen equivalent weight is variable
D.	Oxygen atomic weight is variable
Answer» D. Oxygen atomic weight is variable

Discussion

4204.	Which one of the following pairs of compounds illustrates the law of multiple proportion [EAMCET 1989]
A.	\[{{H}_{2}}O,\,N{{a}_{2}}O\]
B.	MgO,\[N{{a}_{2}}O\]
C.	\[N{{a}_{2}}O,BaO\]
D.	\[SnC{{l}_{2}},\,SnC{{l}_{4}}\]
Answer» E.

Discussion

4205.	A sample of pure carbon dioxide, irrespective of its source contains 27.27% carbon and 72.73% oxygen. The data support [AIIMS 1992]
A.	Law of constant composition
B.	Law of conservation of mass
C.	Law of reciprocal proportions
D.	Law of multiple proportions
Answer» B. Law of conservation of mass

Discussion

4206.	After a chemical reaction, the total mass of reactants and products [MP PMT 1989]
A.	Is always increased
B.	Is always decreased
C.	Is not changed
D.	Is always less or more
Answer» D. Is always less or more

Discussion

4207.	1.0 g of an oxide of A contained 0.5 g of A. 4.0 g of another oxide of A contained 1.6 g of A. The data indicate the law of
A.	Reciprocal proportions
B.	Constant proportions
C.	Conservation of energy
D.	Multiple proportions
Answer» E.

Discussion

4208.	2 g of hydrogen combine with 16 g of oxygen to form water and with 6 g of carbon to form methane. In carbon dioxide 12 g of carbon are combined with 32 g of oxygen. These figures illustrate the law of
A.	Multiple proportions
B.	Constant proportions
C.	Reciprocal proportions
D.	Conservation of mass
Answer» D. Conservation of mass

Discussion

4209.	An element forms two oxides containing respectively 53.33 and 36.36 percent of oxygen. These figures illustrate the law of
A.	Conservation of mass
B.	Constant proportions
C.	Reciprocal proportions
D.	Multiple proportions
Answer» E.

Discussion

4210.	Hydrogen combines with oxygen to form \[{{H}_{2}}O\] in which 16 g of oxygen combine with 2 g of hydrogen. Hydrogen also combines with carbon to form \[C{{H}_{4}}\] in which 2 g of hydrogen combine with 6 g of carbon. If carbon and oxygen combine together then they will do show in the ratio of
A.	6 : 16 or 12 : 32
B.	6 : 18
C.	1 : 2
D.	12 : 24
Answer» B. 6 : 18

Discussion

4211.	In compound A, 1.00 g nitrogen unites with 0.57 g oxygen. In compound B, 2.00 g nitrogen combines with 2.24 g oxygen. In compound C, 3.00 g nitrogen combines with 5.11 g oxygen. These results obey the following law [CPMT 1971]
A.	Law of constant proportion
B.	Law of multiple proportion
C.	Law of reciprocal proportion
D.	Dalton's law of partial pressure
Answer» C. Law of reciprocal proportion

Discussion

4212.	The law of multiple proportions is illustrated by the two compounds [NCERT 1972]
A.	Sodium chloride and sodium bromide
B.	Ordinary water and heavy water
C.	Caustic soda and caustic potash
D.	Sulphur dioxide and sulphur trioxide
Answer» E.

Discussion

4213.	Which of the following is the best example of law of conservation of mass [NCERT 1975]
A.	12 g of carbon combines with 32 g of oxygen to form 44 g of \[C{{O}_{2}}\]
B.	When 12 g of carbon is heated in a vacuum there is no change in mass
C.	A sample of air increases in volume when heated at constant pressure but its mass remains unaltered
D.	The weight of a piece of platinum is the same before and after heating in air
Answer» B. When 12 g of carbon is heated in a vacuum there is no change in mass

Discussion

4214.	n g of substance X reacts with m g of substance Y to form p g of substance R and q g of substance S. This reaction can be represented as, \[X+Y=R+S\]. The relation which can be established in the amounts of the reactants and the products will be
A.	\[n-m=p-q\]
B.	\[n+m=p+q\]
C.	\[n=m\]
D.	\[p=q\]
Answer» C. \[n=m\]

Discussion

4215.	A sample of calcium carbonate \[(CaC{{O}_{3}})\] has the following percentage composition : Ca = 40%; C = 12%; O = 48% If the law of constant proportions is true, then the weight of calcium in 4 g of a sample of calcium carbonate obtained from another source will be
A.	0.016 g
B.	0.16 g
C.	1.6 g
D.	16 g
Answer» D. 16 g

Discussion

4216.	Carbon and oxygen combine to form two oxides, carbon monoxide and carbon dioxide in which the ratio of the weights of carbon and oxygen is respectively 12 : 16 and 12 : 32. These figures illustrate the
A.	Law of multiple proportions
B.	Law of reciprocal proportions
C.	Law of conservation of mass
D.	Law of constant proportions
Answer» B. Law of reciprocal proportions

Discussion

4217.	Which of the following pairs of substances illustrate the law of multiple proportions [CPMT 1972, 78]
A.	CO and CO2
B.	\[{{H}_{2}}O\text{ and }{{D}_{2}}O\]
C.	\[NaCl\text{ and }NaBr\]
D.	\[MgO\text{ and }Mg{{(OH)}_{2}}\]
Answer» B. \[{{H}_{2}}O\text{ and }{{D}_{2}}O\]

Discussion

4218.	Chemical equations convey quantitative information on the [Orissa JEE 2002]
A.	Type of atoms/molecules taking part in the reaction
B.	Number of atoms/molecules of the reactants and products involved in the reaction
C.	Relative number of moles of reactants and products involved in the reaction
D.	Quantity of reactant consumed and quantity of product formed
Answer» D. Quantity of reactant consumed and quantity of product formed

Discussion

4219.	The rate at which substances react depends on their [MP PMT 1997]
A.	Atomic weight
B.	Molecular weight
C.	Equivalent weight
D.	Active mass
Answer» E.

Discussion

4220.	Theory of ?active mass? indicates that the rate of chemical reaction is directly proportional to the [MP PET 1990]
A.	Equilibrium constant
B.	Properties of reactants
C.	Volume of apparatus
D.	Concentration of reactants
Answer» E.

Discussion

4221.	The law of mass action was enunciated by [MP PMT 1995]
A.	Guldberg and Waage
B.	Bodenstein
C.	Birthelot
D.	Graham
Answer» B. Bodenstein

Discussion

4222.	Under a given set of experimental conditions, with increase in the concentration of the reactants, the rate of a chemical reaction [BHU 1979]
A.	Decreases
B.	Increases
C.	Remains unaltered
D.	First decreases and then increases
Answer» C. Remains unaltered

Discussion

4223.	In a reaction the rate of reaction is proportional to its active mass, this statement is known as [IIT 1979]
A.	Law of mass action
B.	Le-chatelier principle
C.	Faraday law of electrolysis
D.	Law of constant proportion
Answer» B. Le-chatelier principle

Discussion

4224.	For the system \[A(g)+2B(g)\]⇌\[C(g)\], the equilibrium concentrations are 0.06 mole/litre 0.12 mole/litre 0.216 mole/litre. The \[{{K}_{eq}}\] for the reaction is [CPMT 1983]
A.	250
B.	416
C.	\[4\times {{10}^{-3}}\]
D.	125
Answer» B. 416

Discussion

4225.	According to law of mass action rate of a chemical reaction is proportional to [AFMC 2005]
A.	Concentration of reactants
B.	Molar concentration of reactants
C.	Concentration of products
D.	Molar concentration of products
Answer» C. Concentration of products

Discussion

4226.	Pure ammonia is placed in a vessel at temperature where its dissociation constant (\[\alpha \]) is appreciable. At equilibrium [IIT 1984; Kurukshetra CEE 1998]
A.	\[{{K}_{p}}\] does not change significantly with pressure
B.	\[\alpha \] does not change with pressure
C.	Concentration of \[N{{H}_{3}}\] does not change with pressure
D.	Concentration of \[{{H}_{2}}\] is less than that of \[{{N}_{2}}\]
Answer» B. \[\alpha \] does not change with pressure

Discussion

4227.	5 moles of SO2 and 5 moles of O2 are allowed to react to form SO3 in a closed vessel. At the equilibrium stage 60% of SO2 is used up. The total number of moles of SO2, O2 and SO3 in the vessel now is [KCET 2001]
A.	10.0
B.	8.5
C.	10.5
D.	3.9
Answer» C. 10.5

Discussion

4228.	0.6 mole of NH3 in a reaction vessel of 2dm3 capacity was brought to equilibrium. The vessel was then found to contain 0.15 mole of H2 formed by the reaction \[2N{{H}_{3(g)}}={{N}_{2(g)}}+3{{H}_{2(g)}}\] Which of the following statements is true [KCET 1999]
A.	0.15 mole of the original NH3 had dissociated at equilibrium
B.	0.55 mole of ammonia is left in the vessel
C.	At equilibrium the vessel contained 0.45 mole of \[{{N}_{2}}\]
D.	The concentration of NH3 at equilibrium is 0.25 mole per dm3
Answer» E.

Discussion

4229.	For the reaction : \[{{H}_{2(g)}}+C{{O}_{2(g)}}\] ⇌\[C{{O}_{(g)}}+{{H}_{2}}{{O}_{(g)}}\], if the initial concentration of \[[{{H}_{2}}]=[C{{O}_{2}}]\] and \[x\] moles/litre of hydrogen is consumed at equilibrium, the correct expression of \[{{K}_{p}}\] is [Orissa JEE 2005]
A.	\[\frac{{{x}^{2}}}{{{(1-x)}^{2}}}\]
B.	\[\frac{{{(1+x)}^{2}}}{{{(1-x)}^{2}}}\]
C.	\[\frac{{{x}^{2}}}{{{(2+x)}^{2}}}\]
D.	\[\frac{{{x}^{2}}}{1-{{x}^{2}}}\]
Answer» B. \[\frac{{{(1+x)}^{2}}}{{{(1-x)}^{2}}}\]

Discussion

4230.	When \[NaN{{O}_{3}}\] is heated in a closed vessel, \[{{O}_{2}}\] is liberated and \[NaN{{O}_{2}}\] is left behind. At equilibrium [IIT 1986; Roorkee 1995]
A.	Addition of \[NaN{{O}_{3}}\] favours forward reaction
B.	Addition of \[NaN{{O}_{2}}\] favours reverse reaction
C.	Increasing pressure favours reverse reaction
D.	Increasing temperature favours forward reaction
Answer» B. Addition of \[NaN{{O}_{2}}\] favours reverse reaction

Discussion

4231.	What is the effect of halving the pressure by doubling the volume on the following system at 500°C \[{{H}_{2(g)}}+{{I}_{2(g)}}\]⇌ \[2H{{I}_{(g)}}\] [UPSEAT 2004]
A.	Shift to product side
B.	Shift to product formation
C.	Liquefaction of HI
D.	No effect
Answer» E.

Discussion

4232.	The equilibrium constant in a reversible reaction at a given temperature [AIIMS 1982]
A.	Depends on the initial concentration of the reactants
B.	Depends on the concentration of the products at equilibrium
C.	Does not depend on the initial concentrations
D.	It is not characteristic of the reaction
Answer» D. It is not characteristic of the reaction

Discussion

4233.	For a reaction \[{{H}_{2}}+{{I}_{2}}\]⇌\[2HI\]at 721K, the value of equilibrium constant is 50. If 0.5 mols each of \[{{H}_{2}}\]and \[{{I}_{2}}\]is added to the system the value of equilibrium constant will be [DCE 2004]
A.	40
B.	60
C.	50
D.	30
Answer» D. 30

Discussion

4234.	2 mol of \[{{N}_{2}}\] is mixed with 6 mol of \[{{H}_{2}}\]in a closed vessel of one litre capacity. If 50% of \[{{N}_{2}}\]is converted into \[N{{H}_{3}}\]at equilibrium, the value of \[{{K}_{c}}\]for the reaction \[{{N}_{2(g)}}+3{{H}_{2(g)}}\] ⇌\[2N{{H}_{3(g)}}\]is [Kerala PMT 2004]
A.	\[4/27\]
B.	\[27/4\]
C.	\[1/27\]
D.	24
E.	9
Answer» B. \[27/4\]

Discussion

4235.	Ammonia carbonate when heated to 200°C gives a mixture of \[N{{H}_{3}}\] and \[C{{O}_{2}}\]vapour with a density of 13.0. What is the degree of dissociation of ammonium carbonate [Kerala PMT 2004]
A.	\[3/2\]
B.	\[1/2\]
C.	2
D.	1
E.	\[5/2\]
Answer» E. \[5/2\]

Discussion

4236.	In the reaction, \[{{H}_{2}}+{{I}_{2}}\]⇌\[2HI\]. In a 2 litre flask 0.4 moles of each \[{{H}_{2}}\] and \[{{I}_{2}}\] are taken. At equilibrium 0.5 moles of \[HI\] are formed. What will be the value of equilibrium constant, \[{{K}_{c}}\] [CPMT 2004]
A.	20.2
B.	25.4
C.	0.284
D.	11.1
Answer» E.

Discussion

4237.	What is the equilibrium expression for the reaction \[{{P}_{4(s)}}+5{{O}_{2(g)}}\]⇌ \[{{P}_{4}}{{O}_{10(s)}}\] [AIEEE 2004]
A.	\[{{K}_{c}}={{[{{O}_{2}}]}^{5}}\]
B.	\[{{K}_{c}}=[{{P}_{4}}{{O}_{10}}]/5[{{P}_{4}}][{{O}_{2}}]\]
C.	\[{{K}_{c}}=[{{P}_{4}}{{O}_{10}}]/[{{P}_{4}}]{{[{{O}_{2}}]}^{5}}\]
D.	\[{{K}_{c}}=1/{{[{{O}_{2}}]}^{5}}\]
Answer» E.

Discussion

4238.	The equilibrium constant for the reaction \[{{N}_{2(g)}}+{{O}_{2(g)}}\]⇌ \[2N{{O}_{(g)}}\] at temperature T is \[4\times {{10}^{-4}}\]. The value of \[{{K}_{c}}\]for the reaction \[N{{O}_{(g)}}\]⇌\[\frac{1}{2}{{N}_{2(g)}}+\frac{1}{2}{{O}_{2(g)}}\] at the same temperature is [AIEEE 2004]
A.	\[4\times {{10}^{-4}}\]
B.	\[50\]
C.	\[2.5\times {{10}^{2}}\]
D.	0.02
Answer» C. \[2.5\times {{10}^{2}}\]

Discussion

4239.	Calculate the partial pressure of carbon monoxide from the following \[CaC{{O}_{3(s)}}\xrightarrow{\Delta }Ca{{O}_{(s)}}+C{{O}_{2}}\uparrow \]; \[{{K}_{p}}=8\times {{10}^{-2}}\] \[C{{O}_{2(g)}}+{{C}_{(s)}}\to 2C{{O}_{(g)}}\] ; \[{{K}_{p}}=2\]\[\] [Orissa JEE 2004]
A.	0.2
B.	0.4
C.	1.6
D.	4
Answer» C. 1.6

Discussion

4240.	The compound A and B are mixed in equimolar proportion to form the products, \[A+B\] ⇌ \[C+D\]. At equilibrium, one third of A and B are consumed. The equilibrium constant for the reaction is [KCET 2004]
A.	0.5
B.	4.0
C.	2.5
D.	0.25
Answer» E.

Discussion

4241.	The reaction, \[2S{{O}_{2(g)}}+{{O}_{2(g)}}\]⇌ \[2S{{O}_{3(g)}}\] is carried out in a 1\[d{{m}^{3}}\]vessel and \[2\ d{{m}^{3}}\]vessel separately. The ratio of the reaction velocities will be [KCET 2004]
A.	\[1:8\]
B.	\[1:4\]
C.	\[4:1\]
D.	\[8:1\]
Answer» E.

Discussion

4242.	56 g of nitrogen and 8 g hydrogen gas are heated in a closed vessel. At equilibrium 34 g of ammonia are present. The equilibrium number of moles of nitrogen, hydrogen and ammonia are respectively [KCET 2004]
A.	1,2,2
B.	2,2,1
C.	1,1,2
D.	2,1,2
Answer» D. 2,1,2

Discussion

4243.	A reversible chemical reaction having two reactants in equilibrium. If the concentrations of the reactants are doubled, then the equilibrium constant will [CPMT 1982, 90; MP PMT 1990,2004; MNR 1992; UPSEAT 2002; KCET 1999; Pb. CET 2004]
A.	Also be doubled
B.	Be halved
C.	Become one-fourth
D.	Remain the same
Answer» E.

Discussion

4244.	3.2 moles of hydrogen iodide were heated in a sealed bulb at \[{{444}^{o}}C\] till the equilibrium state was reached. Its degree of dissociation at this temperature was found to be 22%. The number of moles of hydrogen iodide present at equilibrium are [BHU 1982]
A.	2.496
B.	1.87
C.	2
D.	4
Answer» B. 1.87

Discussion

4245.	For the reaction equilibrium \[{{N}_{2}}{{O}_{4}}\]⇌\[2N{{O}_{2(g)}}\], the concentrations of \[{{N}_{2}}{{O}_{4}}\] and \[N{{O}_{2}}\] at equilibrium are \[4.8\times {{10}^{-2}}\]and \[1.2\times {{10}^{-2}}\,mol\,litr{{e}^{-1}}\] respectively. The value of \[{{K}_{c}}\] for the reaction is [AIEEE 2003]
A.	\[3.3\times {{10}^{2}}\]\[mol\,\,litr{{e}^{-1}}\]
B.	\[3\times {{10}^{-1}}\]\[mol\,\,litr{{e}^{-1}}\]
C.	\[3\times {{10}^{-3}}\]\[mol\,\,litr{{e}^{-1}}\]
D.	\[3\times {{10}^{3}}\]\[mol\,\,litr{{e}^{-1}}\]
Answer» D. \[3\times {{10}^{3}}\]\[mol\,\,litr{{e}^{-1}}\]

Discussion

4246.	In the reaction \[PC{{l}_{5(g)}}\]⇌ \[PC{{l}_{3(g)}}\]\[+C{{l}_{2(g)}}.\] The equilibrium concentrations of \[PC{{l}_{5}}\] and \[PC{{l}_{3}}\] are 0.4 and 0.2 mole/litre respectively. If the value of \[{{K}_{c}}\]is 0.5 what is the concentration of \[C{{l}_{2}}\] in moles/litre [EAMCET 2003]
A.	2.0
B.	1.5
C.	1.0
D.	0.5
Answer» D. 0.5

Discussion

4247.	In a reaction, reactant ?A? decomposes 10% in 1 hour, 20% on 2 hour and 30% in 3 hour. The unit of rate constant of this reaction is [MP PET 2003]
A.	\[se{{c}^{-1}}\]
B.	\[mol\,\,litr{{e}^{-1}}\,se{{c}^{-1}}\]
C.	\[litre\,\,mo{{l}^{-1}}\,se{{c}^{-1}}\]
D.	\[litr{{e}^{2}}\,mo{{l}^{-2}}\,se{{c}^{-1}}\]
Answer» C. \[litre\,\,mo{{l}^{-1}}\,se{{c}^{-1}}\]

Discussion

4248.	Two moles of \[N{{H}_{3}}\] when put into a previously evacuated vessel (one litre), partially dissociate into \[{{N}_{2}}\] and \[{{H}_{2}}\]. If at equilibrium one mole of NH3 is present, the equilibrium constant is [MP PET 2003]
A.	3/4 \[mo{{l}^{2}}\,litr{{e}^{-2}}\]
B.	27/64 \[mo{{l}^{2}}\,litr{{e}^{-2}}\]
C.	27/32 \[mo{{l}^{2}}\,litr{{e}^{-2}}\]
D.	27/1 \[mo{{l}^{2}}\,litr{{e}^{-2}}\]
Answer» E.

Discussion

4249.	9.2 grams of \[{{N}_{2}}{{O}_{4(g)}}\] is taken in a closed one litre vessel and heated till the following equilibrium is reached \[{{N}_{2}}{{O}_{4(g)}}\]⇌ \[2N{{O}_{2(g)}}\]. At equilibrium, 50% \[{{N}_{2}}{{O}_{4(g)}}\] is dissociated. What is the equilibrium constant (in mol litre?1) (Molecular weight of \[{{N}_{2}}{{O}_{4}}=92)\] [MP PET 2003]
A.	0.1
B.	0.4
C.	0.2
D.	2
Answer» D. 2

Discussion

4250.	Write the equilibrium constant K for \[C{{H}_{3}}COOH+{{H}_{2}}O={{H}_{3}}{{O}^{+}}+C{{H}_{3}}CO{{O}^{-}}\] [Kerala (Med.) 2002]
A.	\[K=\frac{[{{H}_{3}}{{O}^{+}}][{{H}_{2}}O]}{[C{{H}_{3}}CO{{O}^{-}}][C{{H}_{3}}COOH]}\]
B.	\[K=\frac{[{{H}_{3}}{{O}^{+}}][C{{H}_{3}}CO{{O}^{-}}]}{[{{H}_{2}}O][C{{H}_{3}}COOH]}\]
C.	\[K=\frac{[{{H}_{3}}{{O}^{+}}][{{H}_{2}}O]}{[C{{H}_{3}}COOH][C{{H}_{3}}CO{{O}^{-}}]}\]
D.	\[K=\frac{[{{H}_{2}}O][C{{H}_{3}}CO{{O}^{-}}]}{[{{H}_{2}}O][C{{H}_{3}}COOH]}\]
Answer» C. \[K=\frac{[{{H}_{3}}{{O}^{+}}][{{H}_{2}}O]}{[C{{H}_{3}}COOH][C{{H}_{3}}CO{{O}^{-}}]}\]

Discussion

Explore topic-wise MCQs in Joint Entrance Exam - Main (JEE Main).

The percentage of copper and oxygen in samples of \[CuO\] obtained by different methods were found to be the same. This illustrates the law of [AMU 1982, 92]

Among the following pairs of compounds, the one that illustrates the law of multiple proportions is

The law of definite proportions is not applicable to nitrogen oxide because [EAMCET 1981]

Which one of the following pairs of compounds illustrates the law of multiple proportion [EAMCET 1989]

A sample of pure carbon dioxide, irrespective of its source contains 27.27% carbon and 72.73% oxygen. The data support [AIIMS 1992]

After a chemical reaction, the total mass of reactants and products [MP PMT 1989]

1.0 g of an oxide of A contained 0.5 g of A. 4.0 g of another oxide of A contained 1.6 g of A. The data indicate the law of

2 g of hydrogen combine with 16 g of oxygen to form water and with 6 g of carbon to form methane. In carbon dioxide 12 g of carbon are combined with 32 g of oxygen. These figures illustrate the law of

An element forms two oxides containing respectively 53.33 and 36.36 percent of oxygen. These figures illustrate the law of

Hydrogen combines with oxygen to form \[{{H}_{2}}O\] in which 16 g of oxygen combine with 2 g of hydrogen. Hydrogen also combines with carbon to form \[C{{H}_{4}}\] in which 2 g of hydrogen combine with 6 g of carbon. If carbon and oxygen combine together then they will do show in the ratio of

In compound A, 1.00 g nitrogen unites with 0.57 g oxygen. In compound B, 2.00 g nitrogen combines with 2.24 g oxygen. In compound C, 3.00 g nitrogen combines with 5.11 g oxygen. These results obey the following law [CPMT 1971]

The law of multiple proportions is illustrated by the two compounds [NCERT 1972]

Which of the following is the best example of law of conservation of mass [NCERT 1975]

n g of substance X reacts with m g of substance Y to form p g of substance R and q g of substance S. This reaction can be represented as, \[X+Y=R+S\]. The relation which can be established in the amounts of the reactants and the products will be

A sample of calcium carbonate \[(CaC{{O}_{3}})\] has the following percentage composition : Ca = 40%; C = 12%; O = 48% If the law of constant proportions is true, then the weight of calcium in 4 g of a sample of calcium carbonate obtained from another source will be

Carbon and oxygen combine to form two oxides, carbon monoxide and carbon dioxide in which the ratio of the weights of carbon and oxygen is respectively 12 : 16 and 12 : 32. These figures illustrate the

Which of the following pairs of substances illustrate the law of multiple proportions [CPMT 1972, 78]

Chemical equations convey quantitative information on the [Orissa JEE 2002]

The rate at which substances react depends on their [MP PMT 1997]

Theory of ?active mass? indicates that the rate of chemical reaction is directly proportional to the [MP PET 1990]

The law of mass action was enunciated by [MP PMT 1995]

Under a given set of experimental conditions, with increase in the concentration of the reactants, the rate of a chemical reaction [BHU 1979]

In a reaction the rate of reaction is proportional to its active mass, this statement is known as [IIT 1979]

For the system \[A(g)+2B(g)\]⇌\[C(g)\], the equilibrium concentrations are 0.06 mole/litre 0.12 mole/litre 0.216 mole/litre. The \[{{K}_{eq}}\] for the reaction is [CPMT 1983]

According to law of mass action rate of a chemical reaction is proportional to [AFMC 2005]

Pure ammonia is placed in a vessel at temperature where its dissociation constant (\[\alpha \]) is appreciable. At equilibrium [IIT 1984; Kurukshetra CEE 1998]

5 moles of SO2 and 5 moles of O2 are allowed to react to form SO3 in a closed vessel. At the equilibrium stage 60% of SO2 is used up. The total number of moles of SO2, O2 and SO3 in the vessel now is [KCET 2001]

0.6 mole of NH3 in a reaction vessel of 2dm3 capacity was brought to equilibrium. The vessel was then found to contain 0.15 mole of H2 formed by the reaction \[2N{{H}_{3(g)}}={{N}_{2(g)}}+3{{H}_{2(g)}}\] Which of the following statements is true [KCET 1999]

For the reaction : \[{{H}_{2(g)}}+C{{O}_{2(g)}}\] ⇌\[C{{O}_{(g)}}+{{H}_{2}}{{O}_{(g)}}\], if the initial concentration of \[[{{H}_{2}}]=[C{{O}_{2}}]\] and \[x\] moles/litre of hydrogen is consumed at equilibrium, the correct expression of \[{{K}_{p}}\] is [Orissa JEE 2005]

When \[NaN{{O}_{3}}\] is heated in a closed vessel, \[{{O}_{2}}\] is liberated and \[NaN{{O}_{2}}\] is left behind. At equilibrium [IIT 1986; Roorkee 1995]

What is the effect of halving the pressure by doubling the volume on the following system at 500°C \[{{H}_{2(g)}}+{{I}_{2(g)}}\]⇌ \[2H{{I}_{(g)}}\] [UPSEAT 2004]

The equilibrium constant in a reversible reaction at a given temperature [AIIMS 1982]

For a reaction \[{{H}_{2}}+{{I}_{2}}\]⇌\[2HI\]at 721K, the value of equilibrium constant is 50. If 0.5 mols each of \[{{H}_{2}}\]and \[{{I}_{2}}\]is added to the system the value of equilibrium constant will be [DCE 2004]

2 mol of \[{{N}_{2}}\] is mixed with 6 mol of \[{{H}_{2}}\]in a closed vessel of one litre capacity. If 50% of \[{{N}_{2}}\]is converted into \[N{{H}_{3}}\]at equilibrium, the value of \[{{K}_{c}}\]for the reaction \[{{N}_{2(g)}}+3{{H}_{2(g)}}\] ⇌\[2N{{H}_{3(g)}}\]is [Kerala PMT 2004]

Ammonia carbonate when heated to 200°C gives a mixture of \[N{{H}_{3}}\] and \[C{{O}_{2}}\]vapour with a density of 13.0. What is the degree of dissociation of ammonium carbonate [Kerala PMT 2004]

In the reaction, \[{{H}_{2}}+{{I}_{2}}\]⇌\[2HI\]. In a 2 litre flask 0.4 moles of each \[{{H}_{2}}\] and \[{{I}_{2}}\] are taken. At equilibrium 0.5 moles of \[HI\] are formed. What will be the value of equilibrium constant, \[{{K}_{c}}\] [CPMT 2004]

What is the equilibrium expression for the reaction \[{{P}_{4(s)}}+5{{O}_{2(g)}}\]⇌ \[{{P}_{4}}{{O}_{10(s)}}\] [AIEEE 2004]

The equilibrium constant for the reaction \[{{N}_{2(g)}}+{{O}_{2(g)}}\]⇌ \[2N{{O}_{(g)}}\] at temperature T is \[4\times {{10}^{-4}}\]. The value of \[{{K}_{c}}\]for the reaction \[N{{O}_{(g)}}\]⇌\[\frac{1}{2}{{N}_{2(g)}}+\frac{1}{2}{{O}_{2(g)}}\] at the same temperature is [AIEEE 2004]

Calculate the partial pressure of carbon monoxide from the following \[CaC{{O}_{3(s)}}\xrightarrow{\Delta }Ca{{O}_{(s)}}+C{{O}_{2}}\uparrow \]; \[{{K}_{p}}=8\times {{10}^{-2}}\] \[C{{O}_{2(g)}}+{{C}_{(s)}}\to 2C{{O}_{(g)}}\] ; \[{{K}_{p}}=2\]\[\] [Orissa JEE 2004]

The compound A and B are mixed in equimolar proportion to form the products, \[A+B\] ⇌ \[C+D\]. At equilibrium, one third of A and B are consumed. The equilibrium constant for the reaction is [KCET 2004]

The reaction, \[2S{{O}_{2(g)}}+{{O}_{2(g)}}\]⇌ \[2S{{O}_{3(g)}}\] is carried out in a 1\[d{{m}^{3}}\]vessel and \[2\ d{{m}^{3}}\]vessel separately. The ratio of the reaction velocities will be [KCET 2004]

56 g of nitrogen and 8 g hydrogen gas are heated in a closed vessel. At equilibrium 34 g of ammonia are present. The equilibrium number of moles of nitrogen, hydrogen and ammonia are respectively [KCET 2004]

A reversible chemical reaction having two reactants in equilibrium. If the concentrations of the reactants are doubled, then the equilibrium constant will [CPMT 1982, 90; MP PMT 1990,2004; MNR 1992; UPSEAT 2002; KCET 1999; Pb. CET 2004]

3.2 moles of hydrogen iodide were heated in a sealed bulb at \[{{444}^{o}}C\] till the equilibrium state was reached. Its degree of dissociation at this temperature was found to be 22%. The number of moles of hydrogen iodide present at equilibrium are [BHU 1982]

In the reaction \[PC{{l}_{5(g)}}\]⇌ \[PC{{l}_{3(g)}}\]\[+C{{l}_{2(g)}}.\] The equilibrium concentrations of \[PC{{l}_{5}}\] and \[PC{{l}_{3}}\] are 0.4 and 0.2 mole/litre respectively. If the value of \[{{K}_{c}}\]is 0.5 what is the concentration of \[C{{l}_{2}}\] in moles/litre [EAMCET 2003]

In a reaction, reactant ?A? decomposes 10% in 1 hour, 20% on 2 hour and 30% in 3 hour. The unit of rate constant of this reaction is [MP PET 2003]

Two moles of \[N{{H}_{3}}\] when put into a previously evacuated vessel (one litre), partially dissociate into \[{{N}_{2}}\] and \[{{H}_{2}}\]. If at equilibrium one mole of NH3 is present, the equilibrium constant is [MP PET 2003]

Write the equilibrium constant K for \[C{{H}_{3}}COOH+{{H}_{2}}O={{H}_{3}}{{O}^{+}}+C{{H}_{3}}CO{{O}^{-}}\] [Kerala (Med.) 2002]