Tag: surface chemistry
Questions Related to surface chemistry
The efficiency of an enzyme to catalyse a reaction is due to its capacity to:
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Reduce the activation energy of the reaction
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Form strong enzyme-substrate complex
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Decrease the bond energies of all substrate molecules
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Alter the substrate geometry to fit into the shape of the enzyme molecule
Enzymes are catalysts for biological reactions. Catalysts have the ability to lower the activation energy barrier of the reaction. The more it reduces the activation energy barrier the more efficient it will be.
The temperature at which the enzyme shows maximum activity is known as _____________ temperature.
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critical
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supportive
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optimum
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none of the above
Each enzyme has a temperature range in which a maximal rate of reaction is achieved. This maximum is known as the optimum temperature of the enzyme. The optimum temperature of each enzyme is different
The effectiveness of a catalyst is minimum at its optimum temperature.
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True
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False
A catalyzed reaction rate is much faster at the optimum temperature of an enzyme. This is a result of increased catalyst activity due to its maximum effectiveness at the optimum temperature
Select the incorrect statement(s).
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Enzyme catalysed reactions are usually hydrolytic in nature
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Enzyme catalysed reactions takes place with evolutions of gases
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The rate of reaction does not depend upon enzyme concentration
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Enzymes are colloidal in nature
The rate of enzyme catalysed reaction depends upon enzyme concentration.
Which of the following is true?
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Enzymes are non - proteinaceous nitrogen containing compounds.
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Amylase convert starch into amylose.
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Biocatalysts, catalyse the reaction occurring in living beings.
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Enzymes are not found in plants.
Enzyme activity is highest in the temperature range of:
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$0-15^o$C
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$15-25^o$C
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$25-45^o$C
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remain same in all
In conversion of sucrose to glucose, the enzyme is:
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zymase
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lipase
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invertase
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diastase
The Enzyme Invertase is used for the conversion of Sucrose to Glucose.
Incorrect statement about a catalyst is?
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It does not alter Gibbs energy, $\Delta G$ of a reaction
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it catalyses both spontaneous and non-spontaneous reactions
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A small amount of catalyst can catalyse a large amount of reaction
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It does not affect equilibrium constant of a reaction
How do enzymes increase the rate of reaction?
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By lowering activation energy
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By increasing activation energy
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By changing equilibrium constant
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By forming enzyme substrate complex
Enzyme catalysis is the increase in the rate of a chemical reaction by the active site of a protein. The protein catalyst (enzyme) may be part of a multi-subunit complex, and/or may transiently or permanently associate with a Cofactor (e.g. adenosine triphosphate). Catalysis of biochemical reactions in the cell is vital due to the very low reaction rates of the uncatalysed reactions. A key driver of protein evolution is the optimization of such catalytic activities via protein dynamics.
They decrease activation energy by providing alternate pathway for process and hence, increase the rate of reaction.
The enzyme ptyalin used for digestion of food is present in:
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saliva
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blood
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intestine
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adrenal gland
They decrease the activation energy by providing alternate pathway (enzyme reacts with the substrate to form an intermediate ES complex, which would be impossible in the absence of the enzyme) for the process.
Enzyme + Substrate → Complex → Product + Enzyme