What does one mean by exothermic and endothermic reactions ? Give examples.
What does one mean by exothermic and endothermic reactions ? Give examples.
Chemical reactions that release energy in the form of heat, light, or sound are called exothermic reactions.
Example : Mixture of sodium and chlorine to yield table salt
$Na _{(s)}+\frac{1}{2} Cl _{2(s)} \longrightarrow NaCl _{( s )}+411 \,kJ$ of energy
In other words, combination reactions are exothermic.
Reactions that absorb energy or require energy in order to proceed are called endothermic reactions.
For example: In the process of photosynthesis, plants use the energy from the sun to convert carbon dioxide and water to glucose and oxygen.
$6C{{O}_{2(g)}}+6{{H}_{2}}{{O}_{(l)}}\text{ }\xrightarrow{\text{Sunlight}}\text{ }\underset{Glucose}{\mathop{{{C}_{6}}{{H}_{12}}{{O}_{6(aq)}}}}\,+6{{O}_{2(g)}}$
Similar Questions
Explain the "Oxidation'' in terms of gain or loss of oxygen with two examples.
Explain the "Oxidation'' in terms of gain or loss of oxygen with two examples.
Identify the substances that are oxidised and the substances that are reduced in the following reactions.
$(i)$ $4 Na ( s )+ O _{2}( g ) \rightarrow 2 Na _{2} O ( s )$
$(ii)$ $CuO ( s )+ H _{2}( g ) \rightarrow Cu ( s )+ H _{2} O ( l )$
Identify the substances that are oxidised and the substances that are reduced in the following reactions.
$(i)$ $4 Na ( s )+ O _{2}( g ) \rightarrow 2 Na _{2} O ( s )$
$(ii)$ $CuO ( s )+ H _{2}( g ) \rightarrow Cu ( s )+ H _{2} O ( l )$
Write the balanced equation for the following chemical reactions.
$(i)$ Hydrogen $+$ Chlorine $\to $ Hydrogen chloride
$(ii)$ Barium chloride $+$ Aluminium sulphate $\to $ Barium sulphate $+$ Aluminium chloride
$(iii)$ Sodium $+$ Water $\to $ Sodium hydroxide $+$ Hydrogen
Write the balanced equation for the following chemical reactions.
$(i)$ Hydrogen $+$ Chlorine $\to $ Hydrogen chloride
$(ii)$ Barium chloride $+$ Aluminium sulphate $\to $ Barium sulphate $+$ Aluminium chloride
$(iii)$ Sodium $+$ Water $\to $ Sodium hydroxide $+$ Hydrogen
In the refining of silver, the recovery of silver from silver nitrate solution involved displacement by copper metal. Write down the reaction involved.
In the refining of silver, the recovery of silver from silver nitrate solution involved displacement by copper metal. Write down the reaction involved.
Balance the following chemical equations.
$(a)$ $HNO _{3}+ Ca ( OH )_{2} \longrightarrow Ca \left( NO _{3}\right)_{2}+ H _{2} O$
$(b)$ $NaOH + H _{2} SO _{4} \longrightarrow Na _{2} SO _{4}+ H _{2} O$
$(c)$ $NaCl + AgNO _{3} \longrightarrow AgCl + NaNO _{3}$
$(d)$ $BaCl _{2}+ H _{2} SO _{4} \longrightarrow BaSO _{4}+ HCl$
Balance the following chemical equations.
$(a)$ $HNO _{3}+ Ca ( OH )_{2} \longrightarrow Ca \left( NO _{3}\right)_{2}+ H _{2} O$
$(b)$ $NaOH + H _{2} SO _{4} \longrightarrow Na _{2} SO _{4}+ H _{2} O$
$(c)$ $NaCl + AgNO _{3} \longrightarrow AgCl + NaNO _{3}$
$(d)$ $BaCl _{2}+ H _{2} SO _{4} \longrightarrow BaSO _{4}+ HCl$