Answer: Energy of reactants = 30, Energy of products = 10
Exothermic
Activation energy for forward reaction is 10.
Explanation:
Exothermic reactions are defined as the reactions in which energy of the product is lesser 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.
Energy of reactants = 30
Energy of products = 10
Thus as energy of the product < energy of the reactant, the reaction is exothermic.
Activation energy 
is the extra energy that must be supplied to reactants in order to cross the energy barrier and thus convert to products.
for forward reaction is (40-30) = 10.
Answer:
It evaporates and moves into the air.
Explanation:
When water is left out for a while, it evaporates into the air! :)
Answer : The correct option is (c) 
Explanation :
The given balanced chemical reaction is,
From the balanced chemical reaction, we conclude that
As, 3 moles of 
react to give 2 mole of 
So, 1 mole of react to give moles of
Thus, the conversion factor needed to convert the number of moles of to the number of moles of produced is
Hence, the correct option is (c)
Answer:
PCl₅ because a subscript indicates 5 chlorine atoms.
Explanation:
As the name suggests, phosphorous pentachloride contains 5 chlorine atoms as penta means five and phosphorous means P atoms.
Answer:
(a)57.48 percent (b) 29.45 percent
Explanation:
copper(II) bromide is 29.45 percent copper and 71.54 percent bromine. so the first element percentage composition is always the percentage composition of the compound.
that goes same with sodium hydroxide. it is 57.48 percent sodium, 40 percent oxygen, and 2.52 percent hydrogen.
