Answer: operating machines they are easy to handle
There’s no picture if you meant to add a picture
Answer:
for combustion of naphthalene is -5164 kJ/mol
Explanation:
where, C refers heat capacity and 
refers change in temperature.
Here, 
So, 
is generally expressed in terms of per mole unit of reactant. Also, should be negative as it is an exothermic reaction (temperature increases).
Molar mass of naphthalene is 128.17 g/mol
So, 1.025 g of naphthalene = 
of naphthalene
= 0.007997 moles of naphthalene
Answer:
Fewer bubbles will be produced because of fewer collisions of reactant molecules
Explanation:
As the solid dissolves into the solution after the liquid has been vigorously bubbled, if the temperature of the liquid is reduced a little, what will happen is that fewer bubbles will be produced as a result of lesser amount of collisions occurring between the reactant molecules
Answer:- 
Solution:- It is a unit conversion where it asks to convert kg of He to atoms. We need to convert kg to grams, grams to moles and finally moles to atoms.
We know that, 1 kg = 1000 g
Molar mass of He is 4.0 grams per mole and 1 mole of an atom equals to Avogadro number of atoms.
The set up would be as given below:
=
So, there are of He in it's 536 kg.
