What is the substance which decreases the rate of a chemical reaction?

What is the substance which decreases the rate of a chemical reaction?
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Poison
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What is the substance which decreases the rate of a chemical reaction? -Do You Know?

Description : What is the substance which decreases the rate of a chemical reaction? -Do You Know?

Last Answer : answer:

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

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 constant of a chemical reaction decreases by decreasing the (A) Pressure (B) Concentration of reactants (C) Temperature (D) Duration of reaction

Description : The rate constant of a chemical reaction decreases by decreasing the (A) Pressure (B) Concentration of reactants (C) Temperature (D) Duration of reaction

Last Answer : (C) Temperature

As the chemical reaction proceeds, the rate of reaction(A) Increases (B) Decreases (C) Remain same (D) May increase or decrease depending on the type of reaction

Description : As the chemical reaction proceeds, the rate of reaction (A) Increases (B) Decreases (C) Remain same (D) May increase or decrease depending on the type of reaction

Last Answer : (B) Decreases

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

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.

(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.

Description : (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 ... may participate in multiple chemical transformations. Catalysts that speed the reaction are called positive catalysts.

Last Answer : 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

"The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances". This is the (A) Lewis-Randall rule (B) Statement of Van't Hoff Equation (C) Le-Chatelier's principle (D) None of these

Description : "The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances". This is the (A) Lewis- ... (B) Statement of Van't Hoff Equation (C) Le-Chatelier's principle (D) None of these

Last Answer : (D) None of these

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

For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant(A) Is independent of pressure(B) Increases with pressure(C) Decreases with pressure(D) Increases /decreases with pressure depending on the stoichiometric co￾efficients of the reaction

Description : For an ideal gas mixture undergoing a reversible gaseous phase chemical reaction, the equilibrium constant (A) Is independent of pressure (B) Increases with pressure (C) Decreases with pressure (D) Increases /decreases with pressure depending on the stoichiometric co￾efficients of the reaction

Last Answer : (B) Increases with pressure

Velocity of a chemical reaction (A) Decreases with increase in temperature (B) Increases with increase of pressure of reactants for all reactions (C) Decreases with increase of reactant concentration (D) None of these

Description : Velocity of a chemical reaction (A) Decreases with increase in temperature (B) Increases with increase of pressure of reactants for all reactions (C) Decreases with increase of reactant concentration (D) None of these

Last Answer : (D) None of these

Fractional conversion __________ for an exothermic reversible chemical reaction, when the temperature is maximum. (A) Increases (B) Remains unchanged (C) Decreases (D) Unpredictable from the data

Description : Fractional conversion __________ for an exothermic reversible chemical reaction, when the temperature is maximum. (A) Increases (B) Remains unchanged (C) Decreases (D) Unpredictable from the data

Last Answer : (C) Decreases

A catalyst in a chemical reaction (A) Decreases the activation energy (B) Alters the reaction mechanism (C) Increases the frequency of collisions of reacting species (D) All (A), (B) and (C)

Description : A catalyst in a chemical reaction (A) Decreases the activation energy (B) Alters the reaction mechanism (C) Increases the frequency of collisions of reacting species (D) All (A), (B) and (C)

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

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

The equilibrium constant of chemical reaction __________ in the presence of catalyst. (A) Increases (B) Decreases (C) Remain unaffected (D) Can either increase or decrease (depends on the type of catalyst)

Description : The equilibrium constant of chemical reaction __________ in the presence of catalyst. (A) Increases (B) Decreases (C) Remain unaffected (D) Can either increase or decrease (depends on the type of catalyst)

Last Answer : (C) Remain unaffected

first order chemical reaction, the concentration of the reactant decreases __________ with time. (A) Linearly (B) Exponentially (C) Logarithmically (D) Inversely

Description : first order chemical reaction, the concentration of the reactant decreases __________ with time. (A) Linearly (B) Exponentially (C) Logarithmically (D) Inversely

Last Answer : (A) Linearly

What substance is always made in a chemical reaction?

Description : What substance is always made in a chemical reaction?

Last Answer : Reactants

Pick out the wrong statement (A) Co-current absorbers are usually used, when the gas to be dissolved in the liquid is a pure substance (B) In case of gas absorption, HETP is equal to HTU, when both the operating line & the equilibrium lines are parallel (C) Hatta number is important in case of gas absorption with chemical reaction (D) In actual practice, absorption is an endothermic process, while stripping is an exothermic process

Description : Pick out the wrong statement (A) Co-current absorbers are usually used, when the gas to be dissolved in the liquid is a pure substance (B) In case of gas absorption, HETP is ... reaction (D) In actual practice, absorption is an endothermic process, while stripping is an exothermic process

Last Answer : (D) In actual practice, absorption is an endothermic process, while stripping is an exothermic process

Half life period of a chemical reaction is (A) The time required to reduce the concentration of the reacting substance to half its initial value (B) Half of the space time of a reaction (C) Half of the residence time of a reaction (D) None of these

Description : Half life period of a chemical reaction is (A) The time required to reduce the concentration of the reacting substance to half its initial value (B) Half of the space time of a reaction (C) Half of the residence time of a reaction (D) None of these

Last Answer : (A) The time required to reduce the concentration of the reacting substance to half its initial value

Two substances are in equilibrium in a reversible chemical reaction. If the concentration of each substance is doubled, then the value of the equilibrium constant will be (A) Same (B) Doubled (C) Halved (D) One fourth of its original value

Description : Two substances are in equilibrium in a reversible chemical reaction. If the concentration of each substance is doubled, then the value of the equilibrium constant will be (A) Same (B) Doubled (C) Halved (D) One fourth of its original value

Last Answer : (A) Same

The rate at which a chemical substance reacts is proportional to its (A) Active mass (B) Molecular weight (C) Equivalent weight (D) Atomic weigh

Description : The rate at which a chemical substance reacts is proportional to its (A) Active mass (B) Molecular weight (C) Equivalent weight (D) Atomic weigh

Last Answer : (A) Active mass

The rate at which a chemical substance reacts is proportional to its (A) Active mass (B) Equivalent weight (C) Molecular weight (D) None of these

Description : The rate at which a chemical substance reacts is proportional to its (A) Active mass (B) Equivalent weight (C) Molecular weight (D) None of these

Last Answer : (A) Active mass

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

Rate of reaction can be expressed as –dc/dt where dc is small decreasing concentration in time dt seconds, (-) sign indicates that the concentration decreases with time. For every 10 degrees rise of temperature, the rate of reaction is generally. Doubled

Description : Rate of reaction can be expressed as –dc/dt where dc is small decreasing concentration in time dt seconds, (-) sign indicates that the concentration decreases with time. For every 10 degrees rise of temperature, the rate of reaction is generally. Doubled

Last Answer : Which equation gives the relation between specific rate (k) and Temperature ?

Pick out the correct statement. (A) Reaction of NH3 with HNO3 to produce (NH4 )2NO3 is endothermic (B) With increase in NH3 /CO2 ratio, urea yield decreases for a given temperature, pressure and total feed rate (C) Biuret (an intermediate during urea manufacture) is toxic to seeds and animals (D) Both (B) and (C)

Description : Pick out the correct statement. (A) Reaction of NH3 with HNO3 to produce (NH4 )2NO3 is endothermic (B) With increase in NH3 /CO2 ratio, urea yield decreases for a given temperature, pressure and total ... (an intermediate during urea manufacture) is toxic to seeds and animals (D) Both (B) and (C)

Last Answer : (B) With increase in NH3 /CO2 ratio, urea yield decreases for a given temperature, pressure and total feed rate

The catalyst in a second order reversible reaction increases the rate of the forward reaction (A) And decreases that of backward reaction (B) And backward reaction equally (C) Only (D) To a greater extent than that of the backward reaction

Description : The catalyst in a second order reversible reaction increases the rate of the forward reaction (A) And decreases that of backward reaction (B) And backward reaction equally (C) Only (D) To a greater extent than that of the backward reaction

Last Answer : (B) And backward reaction equally

When a catalyst increases the rate of forward reaction, the value of rate constant (A) Increases (B) Decreases (C) Remain same (D) Becomes infinite

Description : When a catalyst increases the rate of forward reaction, the value of rate constant (A) Increases (B) Decreases (C) Remain same (D) Becomes infinite

Last Answer : (A) Increases

In a reversible reaction, a catalyst increases the rate of forward reaction (A) Only(B) To a greater extent than that of the backward reaction(C) And decreases that of the backward reaction(D) And the backward reaction equally

Description : In a reversible reaction, a catalyst increases the rate of forward reaction (A) Only (B) To a greater extent than that of the backward reaction (C) And decreases that of the backward reaction (D) And the backward reaction equally

Last Answer : (D) And the backward reaction equally

The reason why a catalyst increases the rate of reaction is that, it (A) Decreases the energy barrier for reaction (B) Increases the activation energy (C) Decreases the molecular collision diameter (D) None of these

Description : The reason why a catalyst increases the rate of reaction is that, it (A) Decreases the energy barrier for reaction (B) Increases the activation energy (C) Decreases the molecular collision diameter (D) None of these

Last Answer : (A) Decreases the energy barrier for reaction

When an exothermic reversible reaction is conducted adiabatically, the rate of reaction (A) Continuously increases (B) Continuously decreases (C) Passes through a maximum (D) Passes through a minimum

Description : When an exothermic reversible reaction is conducted adiabatically, the rate of reaction (A) Continuously increases (B) Continuously decreases (C) Passes through a maximum (D) Passes through a minimum

Last Answer : (C) Passes through a maximum

With increase in the order of reaction (for all positive reaction orders), the ratio of the volume of mixed reactor to the volume of plug flow reactor (for identical feed composition, flow rate and conversion). (A) Increases (B) Decreases (C) Remain same (D) Increases linearly

Description : With increase in the order of reaction (for all positive reaction orders), the ratio of the volume of mixed reactor to the volume of plug flow reactor (for identical feed composition, flow rate and conversion). (A) Increases (B) Decreases (C) Remain same (D) Increases linearly

Last Answer : (A) Increases

The reaction rate almost gets doubled for 10°C rise in temperature. This is due to the fact that the (A) Increased temperature reduces the activation energy (B) Fraction of molecules having threshold energy increases (C) Collision frequency increases (D) Value of threshold energy decreases

Description : The reaction rate almost gets doubled for 10°C rise in temperature. This is due to the fact that the (A) Increased temperature reduces the activation energy (B) Fraction of molecules having threshold energy increases (C) Collision frequency increases (D) Value of threshold energy decreases

Last Answer : (B) Fraction of molecules having threshold energy increases

Pick out the wrong statement. (A) In a first order reaction, A → products; the reaction becomes slower as it proceeds, because the concentration of A decreases and the rate is proportional to the concentration of A (B) Transition state theory approaches the problem of calculating reaction rates by concentrating on the idea of activated complexes (C) According to the penetration theory, the mass transfer co-efficient decreases, if the exposure time of an eddy to the solute decreases (D) If the rate of an irreversible reaction, A + B → 2C is k.CA .CB , then the reaction is always elementary

Description : Pick out the wrong statement. (A) In a first order reaction, A → products; the reaction becomes slower as it proceeds, because the concentration of A decreases and the rate is proportional to the concentration ... irreversible reaction, A + B → 2C is k.CA .CB , then the reaction is always elementary

Last Answer : (C) According to the penetration theory, the mass transfer co-efficient decreases, if the exposure time of an eddy to the solute decreases

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)

With the increase of pressure, the boiling point of any substance - (1) Increases (2) Decreases (3) Remains Same (4) Becomes zero

Description : With the increase of pressure, the boiling point of any substance - (1) Increases (2) Decreases (3) Remains Same (4) Becomes zero

Last Answer : (1) Increases Explanation: The temperature stays the same until all the liquid has vaporized. As the temperature of a liquid rises, the pressure of escaping vapor also rises, and at the boiling point ... vapor is equal to that exerted on the liquid by the surrounding air, causing bubbles to form.

With the increase of pressure, the boiling point of any substance – (1) Increases (2) Decreases (3) Remains Same (4) Becomes zero

Description : With the increase of pressure, the boiling point of any substance – (1) Increases (2) Decreases (3) Remains Same (4) Becomes zero

Last Answer : (1) Increases Explanation: The temperature stays the same until all the liquid has vaporized. As the temperature of a liquid rises, the pressure of escaping vapor also rises, and at the boiling point ... vapor is equal to that exerted on the liquid by the surrounding air, causing bubbles to form.

With increase in porosity, the thermal conductivity of a solid substance (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the solid

Description : With increase in porosity, the thermal conductivity of a solid substance (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the solid

Last Answer : (B) Decreases

With increase in temperature, the internal energy of a substance (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the substance

Description : With increase in temperature, the internal energy of a substance (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the substance

Last Answer : (A) Increases

With increase in temperature, the internal energy of a substance (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the substance

Description : With increase in temperature, the internal energy of a substance (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the substance

Last Answer : (A) Increases

Pick out the wrong statement. (A) Surface tension of a substance vanishes at critical point, as there is no distinction between liquid and vapour phases at its critical point (B) Entropy of a system decreases with the evolution of heat (C) Change of internal energy is negative for exothermic reactions (D) The eccentric factor for all materials is always more than one

Description : Pick out the wrong statement. (A) Surface tension of a substance vanishes at critical point, as there is no distinction between liquid and vapour phases at its critical point (B) Entropy of ... is negative for exothermic reactions (D) The eccentric factor for all materials is always more than one

Last Answer : (D) The eccentric factor for all materials is always more than one

If we increase the pressure on a substance (which is at its triple point), then the triple point (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the substance

Description : If we increase the pressure on a substance (which is at its triple point), then the triple point (A) Increases (B) Decreases (C) Remains unchanged (D) May increase or decrease; depends on the substance

Last Answer : (C) Remains unchanged

When a solid melts,  a. the temperature of the substance increases.  b. the temperature of the substance decreases.  c. heat leaves the substance.  d. heat enters the substance.

Description : When a solid melts,  a. the temperature of the substance increases.  b. the temperature of the substance decreases.  c. heat leaves the substance.  d. heat enters the substance.

Last Answer : heat enters the substance.

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

What is called chemical reaction rate?

Description : What is called chemical reaction rate?

Last Answer : The chemical reaction rate is the speed at which reactants are transformed in products.

What are two ways the rate of a chemical reaction can be changed?

Description : What are two ways the rate of a chemical reaction can be changed?

Last Answer : Feel Free to Answer

When a chemical reaction and it and reverse are occurring at the same time and at the same rate the reaction has achieved?

Description : When a chemical reaction and it and reverse are occurring at the same time and at the same rate the reaction has achieved?

Last Answer : equilibrium

Which of these would be expected to increase the rate of a chemical reaction?

Description : Which of these would be expected to increase the rate of a chemical reaction?

Last Answer : increasing temperature

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