(4) None of these Explanation: Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in multiple chemical transformations. Catalysts that speed the reaction are called positive catalysts.

(4) None of these Explanation: Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in multiple chemical transformations. Catalysts that speed the reaction are called positive catalysts.
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Table salt gets moist during rainy season because – (1) sodium chloride is hygroscopic (2) sodium chloride is deliquescent (3) sodium chloride contains some quantity of sodium iodide (4) sodium chloride contains hygroscopic impurities like magnesium chloride
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Which of the following is incorrect about heterogeneous catalysis? a. The most effective catalysts are those which have small surface area b. Seperation of catlyst is easy c. Increase in the rate of reaction is due to decrease in the activation energy d. It is based upon the phenomenon of adsorption

Description : Which of the following is incorrect about heterogeneous catalysis? a. The most effective catalysts are those which have small surface area b. Seperation of catlyst is easy c. Increase in the rate of reaction is due to decrease in the activation energy d. It is based upon the phenomenon of adsorption

Last Answer : a. The most effective catalysts are those which have small surface area

Which one of the following statements regarding a catalyst is not correct? A An enzyme is a catalyst that only binds certain substrates. B An enzyme is a protein that is a highly efficient catalyst for one or more chemical reactions in a living system. C Catalysts increase the rate of a reaction by altering the mechanism, thereby increasing the activation energy. D Catalysts do not alter the equilibrium constant for a chemical reaction.

Description : Which one of the following statements regarding a catalyst is not correct? A An enzyme is a catalyst that only binds certain substrates. B An enzyme is a protein that is a highly ... increasing the activation energy. D Catalysts do not alter the equilibrium constant for a chemical reaction.

Last Answer : C Catalysts increase the rate of a reaction by altering the mechanism, thereby increasing the activation energy.

Pick out the wrong statement. (A) Use of different catalysts in a reversible catalytic chemical reaction does not change the equilibrium composition (B) Alumina is added as a promoter to iron catalyst in ammonia synthesis reaction (C) Activation energy for a reaction is obtained from the intercept of the Arrhenius plot (D) Presence of inerts affects the equilibrium conversion of reactants in a chemical reaction

Description : Pick out the wrong statement. (A) Use of different catalysts in a reversible catalytic chemical reaction does not change the equilibrium composition (B) Alumina is added as a promoter to ... Arrhenius plot (D) Presence of inerts affects the equilibrium conversion of reactants in a chemical reaction

Last Answer : (C) Activation energy for a reaction is obtained from the intercept of the Arrhenius plot

Substances that cause a reaction to occur or proceed at a different rate without the reaction itself being affected are called - (1) Catalysts (2) Hydrocarbons (3) Oxidising agents (4) Substitutes

Description : Substances that cause a reaction to occur or proceed at a different rate without the reaction itself being affected are called - (1) Catalysts (2) Hydrocarbons (3) Oxidising agents (4) Substitutes

Last Answer : (1) Catalysts Explanation: Catalysts are substances that cause a reaction to occur or proceed at a different rate without the reaction itself being affected. Eg: hydrogenation of vegetable oils using a nickel catalyst.

Which is not true about inorganic catalysts and enzymes? (A) They are specific (B) Inorganic catalysts require specific not needed by enzymes (C) They are sensitive to pH (D) They speed up the rate of chemical reaction

Description : Which is not true about inorganic catalysts and enzymes? (A) They are specific (B) Inorganic catalysts require specific not needed by enzymes (C) They are sensitive to pH (D) They speed up the rate of chemical reaction

Last Answer : Answer : B

A catalyst is a substance which (a) stops a chemical reaction (b) helps initiate a reaction (c) increases the speed of a reaction (d) decreases the speed of a reaction

Description : A catalyst is a substance which (a) stops a chemical reaction (b) helps initiate a reaction (c) increases the speed of a reaction (d) decreases the speed of a reaction

Last Answer : Ans:(c)

Catalyst is a substance, which __________ chemical reaction. (A) Increases the speed of a (B) Decreases the speed of a (C) Can either increase or decrease the speed of a (D) Alters the value of equilibrium constant in a reversible

Description : Catalyst is a substance, which __________ chemical reaction. (A) Increases the speed of a (B) Decreases the speed of a (C) Can either increase or decrease the speed of a (D) Alters the value of equilibrium constant in a reversible

Last Answer : (C) Can either increase or decrease the speed of a

Pick out the wrong statement. (A) ****, *** & Vodka are prepared by the formulation of fruit juice, sugar beet & rye respectively (B) Protein catalysts are called enzymes (C) The rate of chemical reaction is independent of the concentration of reactants at high concentration of enzymes (D) Total sugar content in molasses is about 10%

Description : Pick out the wrong statement. (A) Wine, rum & Vodka are prepared by the formulation of fruit juice, sugar beet & rye respectively (B) Protein catalysts are called enzymes (C) The rate ... concentration of reactants at high concentration of enzymes (D) Total sugar content in molasses is about 10%

Last Answer : (D) Total sugar content in molasses is about 10%

Promoter (A) Initiates a chemical reaction and is a catalyst by itself (B) Alters the position of equilibrium in a reversible reaction (C) Increases the number of active centres by increasing the unevenness of catalyst surface and by creating discontinuities in the crystals(D) All (A), (B) and (C)

Description : Promoter (A) Initiates a chemical reaction and is a catalyst by itself (B) Alters the position of equilibrium in a reversible reaction (C) Increases the number of active centres by increasing the unevenness of catalyst surface and by creating discontinuities in the crystals (D) All (A), (B) and (C)

Last Answer : (C) Increases the number of active centres by increasing the unevenness of catalyst surface and by creating discontinuities in the crystals

Organic catalysts differ from the inorganic catalyst in the sense that the former is (A) Active at cryogenic temperatures only (B) Prohibitively costly (C) Proteinous in nature (D) Active at very high temperature only

Description : Organic catalysts differ from the inorganic catalyst in the sense that the former is (A) Active at cryogenic temperatures only (B) Prohibitively costly (C) Proteinous in nature (D) Active at very high temperature only

Last Answer : (C) Proteinous in nature

In autocatalytic reactions, (A) One of the reactants acts as a catalyst (B) One of the products acts as a catalyst (C) Catalysts have very high selectivity (D) No catalyst is used

Description : In autocatalytic reactions, (A) One of the reactants acts as a catalyst (B) One of the products acts as a catalyst (C) Catalysts have very high selectivity (D) No catalyst is used

Last Answer : (B) One of the products acts as a catalyst

Catalyst is a substance which (1) increases the rate of the reaction (2) decreases the rate of reaction (3) has no action on the rate of the reaction (4) None of these

Description : Catalyst is a substance which (1) increases the rate of the reaction (2) decreases the rate of reaction (3) has no action on the rate of the reaction (4) None of these

Last Answer : None of these

The Rate Law expresses the rate of a reaction in terms of the concentrations of the: w) reactants x) products y) by-products z) catalysts

Description : The Rate Law expresses the rate of a reaction in terms of the concentrations of the: w) reactants x) products y) by-products z) catalysts

Last Answer : ANSWER: W -- REACTANTS 

What is the name for a substance that alters the rate of chemical reactions, without being permanently altered itself?

Description : What is the name for a substance that alters the rate of chemical reactions, without being permanently altered itself?

Last Answer : ANSWER: CATALYST

Substance which increase the activity of certain enzymes called (a) Pro-enzyme (b) Iso-enzymes (d) Co-enzymes (d) Catalysis

Description : Substance which increase the activity of certain enzymes called (a) Pro-enzyme (b) Iso-enzymes (d) Co-enzymes (d) Catalysis

Last Answer : c

What happens when a catalyst is added to a system at equilibrium? A The reaction follows an alternative pathway of lower activation energy. B The heat of reaction decreases. C The potential energy of the reactants decreases. D The potential energy of the products decreases. E The rate of chemical reaction decreases.

Description : What happens when a catalyst is added to a system at equilibrium? A The reaction follows an alternative pathway of lower activation energy. B The heat of reaction decreases. C The potential ... decreases. D The potential energy of the products decreases. E The rate of chemical reaction decreases.

Last Answer : A The reaction follows an alternative pathway of lower activation energy.

A compound, C15H24, is reacted with excess hydrogen using a metal catalyst. One equivalent of the compound consumed three equivalents of hydrogen. Howmany rings did the original compound have? (a) 1 only (b) 2 only (c) 3 only (d) None of these

Description : A compound, C15H24, is reacted with excess hydrogen using a metal catalyst. One equivalent of the compound consumed three equivalents of hydrogen. How many rings did the original compound have? (a) 1 only (b) 2 only (c) 3 only (d) None of these

Last Answer : 1 only

A catalyst is a substance which (a) Changes the equilibrium of a reaction so that the concentration of the product increases (b) Increases the rate of reaction and increases the equilibrium concentration of products (c) Hastens the attainment of equilibrium (d) Increases the activation energy

Description : A catalyst is a substance which (a) Changes the equilibrium of a reaction so that the concentration of the product increases (b) Increases the rate of reaction and increases the equilibrium concentration of products (c) Hastens the attainment of equilibrium (d) Increases the activation energy

Last Answer : Ans:(c)

Enzymes are different from catalysts in (A) Being proteinaceous (B) Not used up in reaction (C) Functional at high temperature (D) Having high rate of diffusion

Description : Enzymes are different from catalysts in (A) Being proteinaceous (B) Not used up in reaction (C) Functional at high temperature (D) Having high rate of diffusion

Last Answer : Answer : A

Enzymes (a protein) are catalysts found in organisms. Its efficiency of catalysing a reaction is due to its capacity to lower the activation energy of the reaction. The enzyme ptyalin used for food digestion is present in (A) Blood (B) Saliva (C) Intestine (D) Gland

Description : Enzymes (a protein) are catalysts found in organisms. Its efficiency of catalysing a reaction is due to its capacity to lower the activation energy of the reaction. The enzyme ptyalin used for food digestion is present in (A) Blood (B) Saliva (C) Intestine (D) Gland

Last Answer : (B) Saliva

Unlike a computer virus, a ……….. can replicate itself automatically. -Technology

Description : Unlike a computer virus, a ……….. can replicate itself automatically. -Technology

Last Answer : Unlike a computer virus, a wormcan replicate itself automatically.

A family of organic compounds whose molecules will add water under an acid catalysis and change into alcohols are the: w) alkenes x) alkanes y) aromatic hydrocarbons z) cycloalkanes

Description : A family of organic compounds whose molecules will add water under an acid catalysis and change into alcohols are the: w) alkenes x) alkanes y) aromatic hydrocarbons z) cycloalkanes

Last Answer : ANSWER: W -- ALKENES

A catalyst inhibitor (A) Lessens its selectivity (B) May be useful for suppressing undesirable side reactions (C) Is added in small quantity during the catalyst manufacture itself (D) All (A), (B) and (C

Description : A catalyst inhibitor (A) Lessens its selectivity (B) May be useful for suppressing undesirable side reactions (C) Is added in small quantity during the catalyst manufacture itself (D) All (A), (B) and (C

Last Answer : (D) All (A), (B) and (C

Arrhenius equation K = Ae-E a / R T In some reactions, Rate of reaction is directly proportional to. Concentration of catalyst Catalyst used in Bio-Chemical reactions is called. Enzymes Reactions catalyzed by light are called as. Photo catalyzed or Photosensitised reactions

Description : Arrhenius equation K = Ae-E a / R T In some reactions, Rate of reaction is directly proportional to. Concentration of catalyst Catalyst used in Bio-Chemical reactions is called. Enzymes Reactions catalyzed by light are called as. Photo catalyzed or Photosensitised reactions

Last Answer : Define order of reaction

(4) Water drops in a dispersion medium of air Explanation: A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium) in which the colloid is dispersed. A colloidal system may be solid, liquid, or gas. Cloud is a colloidal dispersion of Water drops in a dispersion medium of air.

Description : (4) Water drops in a dispersion medium of air Explanation: A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed ... or gas. Cloud is a colloidal dispersion of Water drops in a dispersion medium of air.

Last Answer : Conduction band electrons have more mobility than holes because they – (1) are lighter (2) experience collision less frequently (3) have negative charge (4) need less energy to move them

(2) Fat is dispersed in water Explanation: A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium) in which the colloid is dispersed. A colloidal system may be solid, liquid, or gas. Milk is an emulsified colloid of liquid butterfat globules dispersed within a water-based solution.

Description : (2) Fat is dispersed in water Explanation: A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed ... Milk is an emulsified colloid of liquid butterfat globules dispersed within a water-based solution.

Last Answer : The presence of ozone in the stratosphere is responsible for – (1) increasing the average global temperature in recent years (2) higher rate of photosynthesis (3) checking the penetration of ultra-violet rays to the earth (4) supplying oxygen for people travelling in jets

(2) Fat is dispersed in water Explanation: A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium) in which the colloid is dispersed. A colloidal system may be solid, liquid, or gas. Milk is an emulsified colloid of liquid butterfat globules dispersed within a water-based solution.

Description : (2) Fat is dispersed in water Explanation: A colloid is a substance microscopically dispersed evenly throughout another substance. A colloidal system consists of two separate phases: a dispersed ... Milk is an emulsified colloid of liquid butterfat globules dispersed within a water-based solution.

Last Answer : The presence of ozone in the stratosphere is responsible for – (1) increasing the average global temperature in recent years (2) higher rate of photosynthesis (3) checking the penetration of ultra-violet rays to the earth (4) supplying oxygen for people travelling in jets

When a catalyst increases the rate of chemical reaction the rate constant :-

Description : When a catalyst increases the rate of chemical reaction the rate constant :-

Last Answer : When a catalyst increases the rate of chemical reaction the rate constant :- A. Increases B. Decreases C. Remains constant D. Becomes infinite

Rate of a chemical reaction is not influenced by the (A) Catalyst (B) Temperature (C) Reactants concentration (D) Number of molecules of reactants taking part in a reaction

Description : Rate of a chemical reaction is not influenced by the (A) Catalyst (B) Temperature (C) Reactants concentration (D) Number of molecules of reactants taking part in a reaction

Last Answer : (D) Number of molecules of reactants taking part in a reaction

When a catalyst increases the rate of chemical reaction, the rate constant (A) Decreases (B) Increases (C) Remain constant (D) Become infinite

Description : When a catalyst increases the rate of chemical reaction, the rate constant (A) Decreases (B) Increases (C) Remain constant (D) Become infinite

Last Answer : (B) Increases

Rate of a chemical reaction is not affected by the (A) Catalyst(B) Temperature (C) Reactant’s concentration (D) Number of molecules of reactants taking part in the reaction

Description : Rate of a chemical reaction is not affected by the (A) Catalyst (B) Temperature (C) Reactant’s concentration (D) Number of molecules of reactants taking part in the reaction

Last Answer : (D) Number of molecules of reactants taking part in the reaction

The equilibrium constant of a catalytic chemical reaction __________ due to the presence of a catalyst. (A) Increases (B) Decreases (C) Remain unaffected (D) Unpredictable from the data

Description : The equilibrium constant of a catalytic chemical reaction __________ due to the presence of a catalyst. (A) Increases (B) Decreases (C) Remain unaffected (D) Unpredictable from the data

Last Answer : (C) Remain unaffected

Which of the following is not a dimension-less group used in catalysis? (Where, D = dispersion co-efficient, cm2 /sec.D1 = diffusion co-efficient; cm2 /sec L = length of the reactor, cm t = time, sec, v = volumetric flow rate, cm3 /sec. V = volume, cm3 .) (A) Reactor dispersion number (D/vL) (B) Reduced time (vt/V) (C) Thiele modulus L √(k/D1 ) (D) None of these

Description : Which of the following is not a dimension-less group used in catalysis? (Where, D = dispersion co-efficient, cm2 /sec.D1 = diffusion co-efficient; cm2 /sec L = length of the reactor, cm t = time, sec, v = volumetric ... (D/vL) (B) Reduced time (vt/V) (C) Thiele modulus L √(k/D1 ) (D) None of these

Last Answer : (D) None of these

Participation of __________ is involved in the occurrence of a chemical reaction. (A) Protons (B) Neutrons (C) Electrons (D) None of these

Description : Participation of __________ is involved in the occurrence of a chemical reaction. (A) Protons (B) Neutrons (C) Electrons (D) None of these

Last Answer : (C) Electrons

When more than one bank is allowing credit facilities to one party in coordination with each other under a formal arrangement, the arrangement is generally known as___________ A. Consortium B. Syndication C. Multiple Banking D. Participation

Description : When more than one bank is allowing credit facilities to one party in coordination with each other under a formal arrangement, the arrangement is generally known as___________ A. Consortium B. Syndication C. Multiple Banking D. Participation

Last Answer : A. Consortium Explanation: A banking syndicate formed by multiple banks, often from different countries, for the singular purpose of financing a specific project that is too large for any individual ... in the risk and the profits. Upon completion of the project the consortium bank is disbanded.

Grignard reagents do not show any reaction with (a) Alkoxyalkanes (b) Alkanones (c) Alkyl alkanoates (d) Acyl halides

Description : Grignard reagents do not show any reaction with (a) Alkoxyalkanes (b) Alkanones (c) Alkyl alkanoates (d) Acyl halides

Last Answer : Alkoxyalkanes

Which of the following factors influence whether a reaction will proceed by an SN1, SN2, E1, or E2 mechanism? (a) Structure of the alkyl halide (b) Solvent (c) Concentration of reagents (d) Nature of the nucleophile (e) All of these

Description : Which of the following factors influence whether a reaction will proceed by an SN1, SN2, E1, or E2 mechanism? (a) Structure of the alkyl halide (b) Solvent (c) Concentration of reagents (d) Nature of the nucleophile (e) All of these

Last Answer : All of these

What organic molecule function as a catalysts for chemical reactions in living organisms?

Description : What organic molecule function as a catalysts for chemical reactions in living organisms?

Last Answer : They are called enzymes, but there a probably billions of different enzymes. They are built from protein molecules decorated with sugars and sometimes include one or more metal atoms at their "active" site.

. Photo-chemical reactions occur in presence of (A) Sunlight (B) Darkness (C) Solid catalysts (D) Monochromatic radiation only

Description : . Photo-chemical reactions occur in presence of (A) Sunlight (B) Darkness (C) Solid catalysts (D) Monochromatic radiation only

Last Answer : (A) Sunlight

Enzymes are organic catalysts used in the __________ reactions. (A) Chemical (B) Biochemical (C) Photochemical (D) Electrochemical

Description : Enzymes are organic catalysts used in the __________ reactions. (A) Chemical (B) Biochemical (C) Photochemical (D) Electrochemical

Last Answer : (B) Biochemical

Assertion :- Catalyst change Gibbs free energy of system. Reason :- Catalyst changes preexponential factor of a chemical reaction.

Description : Assertion :- Catalyst change Gibbs free energy of system. Reason :- Catalyst changes preexponential factor of a chemical reaction.

Last Answer : Assertion :- Catalyst change Gibbs free energy of system. Reason :- Catalyst changes preexponential factor ... . If both Assertion & Reason are false.

A catalyst in a chemical reaction __________ free energy change in the reaction. (A) Increases (B) Decreases (C) Either (A) or (B); depends on the type of catalyst (D) Neither (A) nor (B)

Description : A catalyst in a chemical reaction __________ free energy change in the reaction. (A) Increases (B) Decreases (C) Either (A) or (B); depends on the type of catalyst (D) Neither (A) nor (B)

Last Answer : (C) Either (A) or (B); depends on the type of catalyst

The role of a catalyst in a chemical reaction is to change the (A) Equilibrium constant (B) Activation energy (C) Final products (D) Heat of reaction

Description : The role of a catalyst in a chemical reaction is to change the (A) Equilibrium constant (B) Activation energy (C) Final products (D) Heat of reaction

Last Answer : (B) Activation energy

Catalytic action in a catalytic chemical reaction follows from the ability of catalyst to change the (A) Activation energy (B) Equilibrium constant (C) Heat of reaction (D) None of these

Description : Catalytic action in a catalytic chemical reaction follows from the ability of catalyst to change the (A) Activation energy (B) Equilibrium constant (C) Heat of reaction (D) None of these

Last Answer : (A) Activation energy

Which of the reactions between the following pairs of reagents proceeds by a mechanism that may be described as an electrophilic substitution? (a) Benzene + Br2/FeBr3 (b) Propene + Br2 (c) Acetone + NH2NH2 (d) Ethyl bromide + aq KOH

Description : Which of the reactions between the following pairs of reagents proceeds by a mechanism that may be described as an electrophilic substitution? (a) Benzene + Br2/FeBr3 (b) Propene + Br2 (c) Acetone + NH2NH2 (d) Ethyl bromide + aq KOH

Last Answer : Benzene + Br2/FeBr3

The energy consumed by an AC motor, as strictly reactive power, is _____________. A. used to do mechanical work B. used to establish the magnetic field of the motor C. lost as heat generated by the windings D. lost in doing work to turn the motor itself

Description : The energy consumed by an AC motor, as strictly reactive power, is _____________. A. used to do mechanical work B. used to establish the magnetic field of the motor C. lost as heat generated by the windings D. lost in doing work to turn the motor itself

Last Answer : Answer: B

What do you mean by activity and selectivity of catalysis?

Description : What do you mean by activity and selectivity of catalysis? 

Last Answer : Ans. Activity of catalyst means to increase the extent of chemisorption. Selectivity of Catalyst means to direct a reaction to form selective product.

What is meant by induced catalysis ? Give an example.

Description : What is meant by induced catalysis ? Give an example.

Last Answer : It is a phenomenon in which a chemical reaction increases the rate of another reaction which otherwise may not occur in similar conditions.  Eg. Sodium arsenite (Na3AsO3 ) is not oxidised in air but if ... a solution containing Na3AsO3 and Na2 SO3 , then both AsO3 3- and SO3 2- ions are oxidised.

Shape-selective catalysis

Description : Shape-selective catalysis

Last Answer : Shape-selective catalysis : A catalytic reaction that depends upon the pore structure of catalyst as well as the size of reactant & product molecules is called Shape-selective catalysis.