Advertisements
Advertisements
प्रश्न
Define endothermic reactions. Give two examples of each.
Advertisements
उत्तर
Endothermic reaction: A chemical reaction in which heat is absorbed is called endothermic reaction. It causes fall in temperature.
e.g. (i) When nitrogen and oxygen together are heated to a temperature of about 3000°C, nitric oxide gas is formed.
N2 + O2 + heat → 2NO (g)
(ii) Decomposition of calcium carbonate into carbon dioxide and calcium oxide when heated to a 1000°C.
CaCO3 + Heat → CaO (s) + CO2 (g)
APPEARS IN
संबंधित प्रश्न
State the effect of an endothermic reaction.
Identify the endothermic and exothermic reaction.
HCl + NaOH → NaCl + H2O + heat
Identify the endothermic and exothermic reaction.
\[\ce{CaCO_{3(s)}->[\Delta] CaO_{(s)} + CO2}\]
Name a compound which produces carbon dioxide on heating.
State which type of chemical reaction proceeds with evolution of heat energy.
Give an example with a balanced equation, of the following reaction:
photochemical reaction
Mention any two exothermic reactions.
Assertion: A drop of petrol when touched with finger gives a chill feeling.
Reason: The above phenomenon is an endothermic one.
Complete the following table:
| Chemical Reactions | Name reaction type |
| \[\ce{C(s) + O2(g) -> CO2(g)}\] | (a) ________ |
| \[\ce{Zn(s) + CuSO4(aq) ->}\] (b) _________ | Displacement reaction |
| \[\ce{2Cu(s) + O2(g) ->[heat] 2CuO(s)}\] | (c) _________ |
| \[\ce{C(s) + 2H2(g) -> CH4(g)}\] | (d) _________ |
| \[\ce{CaO(s) + H2O(l) -> Ca(OH)2(aq) + heat}\] | (e) _________ |
| \[\ce{CaCO3(s) + Heat ->}\] (f) _________ | Endothermic Reaction |
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.
