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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?
light.
Complete and balance the following chemical equations:
Fe `"SO"_4` + NaOH `→`
(aq.) (aq.)
Fill in the blank
A catalyst either ................or ............... the rate of a chemical change but itself remains ............... at the end of the reaction.
TRUE \ FALSE
A precipitation reaction takes place only in a solution.
State four conditions necessary for a chemical reaction to take place.
Explain the following reaction with one suitable example of Combination reactions .
Complete the statement by filling the gaps using appropriate term from the terms given in the bracket.
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What do you observe when Cobalt chloride paper is introduced in water vapour.
What is a chemical reaction?
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| Addition of dil. H2SO4 to zinc | Test for gas evolved |
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\[\ce{Cu++->Cu}\]
State the following reaction represent oxidation or reduction.
\[\ce{H->H+}\]
A chemical reaction is often accompanied by external indications or characteristics.
Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
Zinc carbonate.
The chemical change is ______.
________ is a chemical substance which alters the speed of a chemical reaction.
______ is a natural indicator.
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