Answer:
camphor sublimates salt is soluble in water while sand does not sublime and does not dissolve in water you first heat the mixture in a beaker covered with a watch glass camphor will then accumulate on the watch glass then you dissolve the remaining mixture of sand and salt salt will dissolve forming a salt solution then you filter using a filter paper and a beaker the residue on the filter paper is sand while the filtrate is salt solution you then heat the salt solution so that it can evaporate leaving salt particles thus you will have obtained salt sand and camphor
Answer : The correct option is, (C) 2, 4 and 5.
Explanation :
Combustion reaction : It is a type of reaction in which a hydrocarbon react with an oxygen molecule to give carbon dioxide, water as a product.
For example : Methane react with oxygen to give carbon dioxide and water.

In the given list of chemical substances,
are in oxide form. They can not be both reactant and product of a single combustion reaction.
In the given list,
is the only hydrocarbon which shows a combustion reaction. That means
react with
to give
and
as a product.
The balanced combustion reaction of
is,

Therefore, the correct answer is, (C) 2, 4, and 5.
ΔH2 = - δH1 δH2 = - 2 x δH1 δH2 = 2 x <span>δ</span>H1
Answer: The reaction is exothermic reaction as the energy of products is less than the energy of reactants.
Explanation: Exothermic reactions are defined as the reactions in which energy of the product is less than the energy of the reactants. The total energy is released in the form of heat and
for the reaction comes out to be negative.
Labeling of the parts in the diagram:
A represents the activation energy which is the energy required by reactants to cross the energy barrier to get converted to products.
E represents the potential energy of the reactants.
B represents the activated complex.
D represents the potential energy of the products.
C represents the total enthalpy change of the reaction, which comes out to be negative for exothermic reactions.
