Divide the molar mass of the compound by the empirical formula mass. The result should be a whole number or very close to a whole number. Multiply all the subscripts in the empirical formula by the whole number found in step 2. The result is the molecular formular
It is b I hope this helps
The enthalpy change of the reaction when sodium hydroxide and sulfuric acid react can be calculated using the mass of solution, temperature change, and specific heat of water.
The balanced chemical equation for the reaction can be represented as,

Given volume of the solution = 101.2 mL + 50.6 mL = 151.8 mL
Heat of the reaction, q =
Δ
m is mass of the solution = 151.8 mL * 
C is the specific heat of solution = 4.18 
ΔT is the temperature change = 
q = 
Moles of NaOH =
NaOH
Moles of
= 
Enthalpy of the reaction = 
Explanation:
option option B is the correct answer of given statement helium-4(He)=2