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Consider the endothermic reaction: . A sealed container filled with an equilibrium mixture of and is suddenly immersed in an ice bath. Which of the following changes will occur initially?
The concentration of increases.
The concentration of increases.
The equilibrium constant () increases.
No change occurs.
The solubility of gases in liquids generally:
Increases with increasing temperature
Decreases with increasing temperature
Is independent of temperature
Increases with increasing pressure and decreasing temperature
Which combination of factors would MOST effectively enhance the cleansing action of a soap in hard water?
Decreased temperature and addition of NaCl
Increased temperature and addition of NaCl
Decreased temperature and addition of a chelating agent
Increased temperature and addition of a chelating agent
A researcher isolates an enzyme from a thermophilic bacterium and finds that its activity dramatically decreases when incubated at 25°C compared to its optimal temperature of 70°C. This decrease in activity is MOST likely due to:
Increased substrate affinity at lower temperatures.
Changes in the enzyme's three-dimensional structure affecting the active site.
A decrease in the activation energy of the catalyzed reaction.
An increase in the concentration of competitive inhibitors at lower temperatures.
Given below are two statements:
Statement I: Low temperature preserves the enzyme in a temporarily inactive state whereas high temperature destroys enzymatic activity because proteins are denatured by heat.
Statement II: When the inhibitor closely resembles the substrate in its molecular structure and inhibits the activity of the enzyme, it is known as a competitive inhibitor.
In the light of the above statements, choose the correct answer from the options given below:
Both Statement I and Statement II are true
Both Statement I and Statement II are false
Statement I is correct but Statement II is false
Statement I is incorrect but Statement II is true
Enzymes are proteins that catalyze biological reactions. Which of the following statements regarding enzyme activity and inhibition is INCORRECT?
Low temperatures decrease enzyme activity without causing permanent damage.
High temperatures temporarily inactivate enzymes, allowing them to regain function upon cooling.
Competitive inhibitors compete with the substrate for the enzyme's active site.
Non-competitive inhibitors bind to a site other than the active site and affect enzyme activity.
An enzyme-catalyzed reaction is being studied. Which of the following would NOT be a likely outcome if the temperature is significantly increased?
An increased reaction rate
A decreased reaction rate
Denaturation of the enzyme
Altered substrate specificity
Which statement BEST describes the effect of low temperature on enzyme activity?
Enzyme activity increases due to increased substrate binding.
The enzyme denatures, leading to irreversible loss of activity.
Enzyme activity decreases, but the enzyme is not denatured.
The enzyme becomes permanently activated.
Statement-1: If temperature is increased, the dielectric constant of a polar dielectric decreases whereas that of a non-polar dielectric does not change significantly. Statement-2: The magniude of dipole moment of individual polar molecule decreases significantly with increase in temperature.
Statement-1 is True, Statement-2 is True
Statement-1 is True, Statement-2 is False
Statement-1 is False, Statement-2 is True
Statement-1 is False, Statement-2 is False
Enzymes catalysts differ from inorganic catalysts in which way?
Enzyme catalysts are smaller in size and lesser in weight in comparision to that of inorganic catalysts
Inorganic catalysts can work efficiently at temperature but enzymes catalyst cannot (except few enzymes)
Inorganic catalysts can work efficiently at high pressure but enzyme catalyst cannot
Both (b) and (c )
