Advertisements
Advertisements
प्रश्न
Give scientific reasons.
While preparing dil. Sulphuric acid from concentrated conc. sulphuric acid in the laboratory the concentrated sulphuric acid is, add slowly to water with constant stirring.
उत्तर
i. This is exothermic process.
ii. if we poured conc. sulphuric acid speedily in a water. Water gets evaporated instantaneously and very large amount of heat is liberated which may cause an accident.
iii. to avoid this, and only small amount of heat is liberated at a time it added slowly to water with constant stirring
APPEARS IN
संबंधित प्रश्न
Explain the term with examples.
Endothermic reaction
Give scientific reason.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
Identify the endothermic and exothermic reaction.
HCl + NaOH → NaCl + H2O + heat
Identify the endothermic and exothermic reaction.
\[\ce{CaO + H2O -> Ca(OH)2 + Heat}\]
Give an example of the following chemical changes.
A photochemical reaction involving silver salt.
State the effects of endothermic and exothermic reactions on the surroundings.
Give an example of the following chemical changes.
An exothermic and an endothermic reaction involving carbon as one of the reactants.
State the following reaction whether heat is evolved or absorbed –
water is added to quicklime
State the following reaction whether heat is evolved or absorbed –
Two neutral gases combine to give a basic gas.
Complete the statement by filling in the blank with the correct word:
The element molybdenum used in the reaction of nitrogen with hydrogen at elevated temperatures is an example of a ________.
Give an example with a balanced equation, of the following reaction:
photochemical reaction
Supply of energy may be required to initiate a reaction. State the different forms with a suitable example of reactions initiated by the supply of energy.
Give examples of the endothermic process.
Give examples for the exothermic process.
Give scientific reasons.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
Give a scientific reason.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
Give scientific reason.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
Give scientific reason.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.