Advertisements
Advertisements
Question
What is a chemical reaction?
Advertisements
Solution
“Chemical reaction is a chemical change in which matter changes into a new substance or substances.”
APPEARS IN
RELATED QUESTIONS
State whether the following statement is true or false. In case a statement is false, write the corrected statement.
Iron pipes coated with zinc do not get rusted easily.
Write the missing reactants and products and balance the equations.
NaOH + ............... `→` NaCI + ...................
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Reduction reaction is the exact opposite of
- displacement reaction
- decomposition reaction
- oxidation reaction
- none of these
FILL IN THE BLANK
A .............. change is a temporary change.
TRUE \ FALSE
Ammonia is a good oxidizing agent.
TRUE \ FALSE
Positively charged electrode is called the anode. True or false ?
What are homogenous reactions ?
How is a strong electrolyte different from a weak electrolyte?
Write true or false.
A chemical equation gives only qualitative information of a chemical reaction.
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.
(slow, coloured, arrow, fast, smell, milky, physical, product, chemical, reactant, covalent, ionic, octet, duplet, exchange, sharing, equality sign)
Chlorine (Cl2) molecule is formed by ______ of electrons between two chlorine atoms.
Choose the correct option from the bracket and explain the statement giving reason.
(Oxidation, displacement, electrolysis, reduction, zinc, copper, double displacement, decomposition)
The conversion of ferrous sulphate to ferric sulphate is ______ reaction.
What do you understand by precipitation reaction? Explain with examples.
Give a chemical test to distinguish between the following gases.
NH3 and SO2
What do you observe when CO2 is passed through lime water first and then a little in excess.
Explain the term ‘chemical reaction’ with special reference to – ‘reactants’ and ‘products’.
A chemical reaction is often accompanied by external indications or characteristics which include –
- Colour change
- Effervescence or gas evolved
- Evolution or absorption of heat
- Formation of a precipitate.
With reference to each of the above indications, state the external indication seen during – Thermal decomposition of mercury [II] oxide.
Explain with the help of balanced equations, how precipitation reactions are used for identifying the positive radicals in three different salts, each having a different cation [positive ion].
Burning of paper is a ______ change.
The percentage composition of Nitrogen in Ureas is ______.
