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प्रश्न
Write true or false .
A black residue is formed when sugar is heated .
विकल्प
True
False
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उत्तर
True
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संबंधित प्रश्न
How do the following help in bringing about a chemical change?
pressure.
How do the following help in bringing about a chemical change?
catalyst .
Complete and balance the following chemical equations:
Zn + `"H"_2"SO"_4` `→`
(dil)
TRUE \ FALSE
A precipitation reaction takes place only in a solution.
Write true or false :
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Give an example of a reaction where the following are involved:
Solution
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What do you observe? When
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Give an example of the following chemical changes.
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Write your observation and a balanced equation in the case of the following substances being heated.
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Complete the statement by filling in the blank with the correct word:
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Higher order Thinking question
A very hot glass on putting in cold water cracks. What does this change indicate?
Chemical change is a temporary change.
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Zinc dissolves in hydrochloric acid with the evolution of hydrogen gas.
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What changes do you expect?
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Write a note on the following:
Fermentation
______ is the chemical name of rust.
