Chemistry
Give examples of exothermic reactions i.e. heat evolved in each of the following:
(a) reaction between a solid and a liquid
(b) reaction between two gases
Give two examples of exothermic reactions seen in everyday life.
Chemical Reaction
46 Likes
Answer
(a) CaO + H2O ⟶ Ca(OH)2 + Δ
(b) 2H2 + O2 ⟶ 2H2O + Δ
Two examples of exothermic reactions from everyday life are:
- Human Body — Many chemical reactions in our body are exothermic and provide energy to survive.
- Setting of Cement — Cement setting liberates heat hence concrete structures are set slowly.
Answered By
24 Likes
Related Questions
In certain reactions a change of smell is observed. Give two examples from daily life of the same.
In certain reactions an insoluble solid called precipitate is formed. State the colour and name of the precipitate formed in each of the following reactions involving addition of:
(a) Dilute hydrochloric acid to silver nitrate
(b) Iron [II] sulphate to sodium hydroxide
(c) Iron [III] chloride to ammonium hydroxide
(d) Copper [II] sulphate to sodium hydroxide
(e) Lead nitrate to ammonium hydroxide
Give one example in each case where supplying energy [given below] is necessary for a chemical reaction.
(a) Heat energy
(b) Light energy
(c) Electrical energy
(d) Pressure
(e) Catalyst
Representation of the results of a chemical change – is a chemical equation.
For the equation: FeCl3 + 3NH4OH ⟶ 3NH4Cl + Fe(OH)3 ↓
Answer the following:
(a) Write the word equation for the above molecular equation.
(b) Is the equation given above a balanced equation. Give reasons.
(c) Name the reactants and the products in the above equation.
(d) What is the indications of the arrow between the reactants and the products and of the arrow pointing downwards at the end.