Chemistry
State whether the following statements are true or false. If false, write- the correct statement.
Desirable changes are meaningful, while undesirable changes are unfavorable.
During physical changes, the composition of the original substance is not altered, but the properties of the original substance are altered.
During a chemical change the composition of the original substance is not altered, and the change is irreversible.
Melting of butter and wax are examples of chemical changes.
The melting of ice is an exothermic, irreversible chemical change.
Phy & Chem Changes
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Answer
True
False.
Corrected Statement — During physical changes, the composition and properties of the original substance are not altered.False.
Corrected Statement — During a chemical change the composition of original substance is altered and the change is irreversible.False.
Corrected Statement — Melting of butter and wax are examples of physical changes.False.
Corrected Statement — Melting of ice is an endothermic, reversible physical change.
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Related Questions
Explain in brief the involvement of energy in - physical & chemical changes.
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Germination of seeds is considered a …………… [physical/chemical] change.
If a change is permanent and irreversible, it is considered a …………… [chemical/physical] change.
Heating a piece of iron is considered a …………… [physical/chemical] change, while heating a piece of coal [carbon] is considered a …………… [physical/chemical] change.
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Change of milk to curd is a …………… [desirable/undesirable] change.
Match the examples of changes in List I with the correct type in List II.
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Sublimation is …………… [considered/not considered] a change of state of matter.
Sublimation involves a …………… [chemical/physical] change.
During sublimation a solid on heating turns directly into …………… [liquid/vapour] & on cooling back to …………… [solid/liquid].
Ammonium chloride, a sublimable solid undergoes …………… [synthesis/dissociation] on heating.
Sublimation of iodine is an example of …………… [physical/chemical] change.