Tag: types of changes
Questions Related to types of changes
When a nail is added to acidic copper sulphate solution, the colour changes from _______.
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blue to green
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green to blue
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blue to pink
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pink to green
When a nail is added to acidic copper sulphate solution, the colour changes from blue to green.
Copper sulphate reacts with iron to form iron sulphate.
Which of the following is true?
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Melting of ice is reversible change.
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Burning of magnesium is reversible change.
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Rusting of iron is reversible change.
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All of the above.
The statement (A) is true.
Melting of ice is reversible change.
Burning of magnesium is irreversible change.
Rusting of iron is irreversible change.
Which of the following is true?
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A physical change can never be reversible.
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A chemical change can never be reversible.
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Both of the above
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A physical change may be reversible.
Also, a chemical change may be reversible.
A physical change may be reversible. For example, melting of ice is a reversible change.
Also, a chemical change may be reversible. For example, the reaction between $\displaystyle N _2$ and $\displaystyle H _2$ to form $\displaystyle NH _3$ is a reversible chemical change.
Choose the incorrect statement(s).
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Chemical reactions are characterized by the change in colour.
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Chemical reactions are not alone characterized by change in state.
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Physical changes are characterized by the change in colour of reacting substances.
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Physical changes are not reversible.
When sugar is stirred with a spoon in a glass of water, more sugar is dissolved and faster. Why?
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Spoon acts as a catalyst
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On stirring, temperature increases
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Stirring increases the rate of interaction
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Spoon increases the attraction between the molecules of water and sugar
Cooking of rice is an example of:
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irreversible change
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endothermic reaction
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both $A$ & $B$
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none of the above
Cooking of rice is both irreversible and endothermic reaction. i.e once cooked rice cannot be made rice back and the rice absorbs heat from the external sources and utilizes for its cooking so it is endothermic.
The growth of seedlings in a crop is a:
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undesirable change
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desirable change
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reversible change
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physical change
The growth of seedlings in a crop is a desirable change i.e the changes which are beneficial to nature or which does not cause any harm to nature.
A seed growing into a tree is an example of:
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slow physical change
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fast periodic change
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slow natural change
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man-made reversible change
A seed growing into a tree is an example of a slow and natural process. Slow because it takes days to sometimes months for a seed to develop into a sapling and then years to a develop into a tree. All these processes occur naturally using all natural resources like water, sunlight, soil.
What's common among motion of the planets around the sun, blinking of traffic lights and motion of blades of a fan rotating at uniform speed?
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Irreversible changes
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Chemical changes
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Periodic changes
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Undesired changes
The planets around the sun, blinking of traffic lights and motion of blades of a fan rotating at uniform speed are all periodic changes.
Changes which are repeated after regular intervals are called periodic changes.
If two substances interact to produce a change, they will do so:
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under any condition
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no matter what kind of interaction there is
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only if the interaction is of the right kind and under the right conditions
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only if they are in close contact with each other
According to transition state theory, two molecules interact with each other when they are aligned in a proper orientation.