Pure Substances
Trending Questions
What is meant by a substance?
Try segregating the things around you as pure substances and mixtures.
Assertion: Ortho and para-nitrophenol can be separated by steam distillation.
Reason: Para-nitrophenol is steam volatile due to intramolecular hydrogen bonding.
Both assertion and reason are true and reason is the correct explanation of assertion.
Both assertion and reason are true but reason is not the correct explanation of assertion.
Assertion is true but reason is false.
Both assertion and reason are false.
Which of the following statements are true for pure substances?
(i) Pure substances contain only one kind of particle.
(ii) Pure substances may be compounds or mixtures.
(iii) Pure substances have the same composition throughout.
(iv) Pure substances can be exemplified by all elements other than nickel.
(i) and (ii)
(i) and (iii)
(iii) and (iv)
(ii) and (iii)
Is air a pure substance?
Milk is a mixture. Give reasons.
Which of the following statements are true for pure substances?
(i) Pure substances contain only one kind of particles
(ii) Pure substances may be compounds or mixtures
(iii) Pure substances have the same composition throughout
(iv) Pure substances can be exemplified by all elements other than nickel
(i) and (ii)
(i) and (iii)
(iii) and (iv)
(ii) and (iii)
Matter that cannot be broken down into simpler substances by chemical reactions is called __________________.
compound
element
molecule
mixture
Is element a pure substance?
Or,
They both are same?
Which of the following are 'pure substances' ?
Ice, Milk, Iron, Hydrochloric acid, Calcium oxide, Mercury, Brick, Wood, Air
Classify the following as element, mixture or compound:
Sea water
Give the names of the elements present in the following compounds:
(c) Baking powder
Is wood a pure substance?
Write the composition of the chemicals in talcum powder.
What are pure substances ? Give two examples of pure substances.
The answer, in brief, is why is tap water a mixture.
Ice placed in water is which kind of mixture?
Explain
Why the interconversion of states of matter is considered a physical change? Give three reasons to justify your answer.
Both elements and compounds have fixed composition and a definite set of properties.
- True
- False
Classify the following as element, mixture, or compound:
Butter
3. Formation of clouds is a physical change. Give reason.
Give reasons for the following:
Pure substances have fixed melting or boiling points.
Classify the following as mixtures: heterogeneous or homogeneous, or pure substances, elements or compounds:
(i) sugar dissolved in water
(ii) sea water
(iii) rust
(iv) sugar
(v) mercury in a thermometer
(vi) steel
(vii) soda water
(viii) sand and water
Which of the following statements are true for pure substances?
(i) Pure substances contain only one kind of particle.
(ii) Pure substances may be compound or mixtures.
(iii) Pure substances have the same composition throughout.
(iv) Pure substances can be exemplified by all elements other than nickel.
(i) and (ii)
(i) and (iii)
(iii) and (iv)
(ii) and (iii)
Crystals having a fixed number of water molecules are known as anhydrous substances.
- True
- False
Reason: Substances containing two or more elements are considered pure.
- Both assertion and reason are correct and reason is the correct explanation for assertion.
- Both assertion and reason are correct but reason is not the correct explanation for assertion.
- Assertion is correct but the reason is incorrect.
- Both the assertion and the reason are incorrect.
Sucrose (sugar) crystals obtained from sugarcane and beetroot are mixed together. Will it be a pure substance or a mixture? Give reasons for the same.
Are all pure substances elements?
