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प्रश्न
Write true or false .
A black residue is formed when sugar is heated .
पर्याय
True
False
उत्तर
True
APPEARS IN
संबंधित प्रश्न
Complete and balance the following chemical equations
NaCI + `AgNO_3` `→`
What do you observe when Iron nail is kept in copper sulphate solution for sometime.
FILL IN THE BLANK
Positively charged ions are called ........
FILL IN THE BLANK
Distillation is a method of obtaining pure ............. from a solution.
TRUE \ FALSE
Copper can displace iron from iron sulphate.
Name three reducing agents ?
How is a strong electrolyte different from a weak electrolyte?
State what you would observe when the following substance is heated in a glass test tube Copper (II) carbonate Red lead .
Complete the statement by filling the gaps using appropriate term from the terms given in the bracket.
(slow, coloured, arrow, fast, smell, milky, physical, product, chemical, reactant, covalent, ionic, octet, duplet, exchange, sharing, equality sign)
Rusting of iron is a ______ chemical change.
Give an example of a reaction where the following are involved
Light
Give an example of the following chemical change.
Two solids combine to form a liquid
Complete and balance the following reaction:
\[\ce{Pb(NO3)2 ->[\Delta]}\]
Complete and balance the following reaction:
\[\ce{NH3 + O2 ->[\Delta]}\]
Name: Gas with rotten egg smell.
Name: A greenish-yellow gas.
Give a chemical test to distinguish between the following gases.
CO2 and SO2
Give a word equation for the following reaction.
Two solids which combine on heating, to give a liquid.
On heating which of the following substances i.e. copper carbonate, zinc carbonate, washing soda, copper sulphate, zinc nitrate, copper nitrate, lead nitrate, ammonium chloride and ammonium dichromate – relate to the reaction given below.
A coloured substance which leaves on strong heating a black residue and evolves two colourless gases one of which is acidic and the other neutral.
On heating which of the following substances i.e. copper carbonate, zinc carbonate, washing soda, copper sulphate, zinc nitrate, copper nitrate, lead nitrate, ammonium chloride and ammonium dichromate – relate to the reaction given below.
A coloured substance which leaves a black residue and evolves two gases one of which is acidic and coloured and the other neutral and colourless.
Give a balanced equation for a reaction involving the evolution of gas on the addition of dilute acid to sodium sulphite.
Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
Lead nitrate.
Assertion: The formation of iron oxide from iron is a chemical change.
Reason: For the rust to form from iron, it must be exposed to air and water.
Rusting of Iron: undesirable change:: Dead plants turn into manure: ______.
Water boiling into water vapour is an example of chemical change.
On heating calcium carbonate gets converted into calcium oxide and carbon dioxide.
(a) Is this a physical or a chemical change?
(b) Can you prepare one acidic and one basic solution by using the products formed in the above process? If so, write the chemical equation involved.
A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about an hour.
What changes do you expect?
Give an example where heat, light, and sound are produced during a chemical change.
______ is the chemical name of limestone.
______ is a chemical substance is used in whitewashing.
What is thermochemical reactions?
