During a phase change the temperature does not change since all of the heat is being absorbed in order to break the intermolecular forces. Due to that, the formula will not need to have T in it and is actually q=nΔH(v).
n=the number of moles (in this case 2.778mol of water since you divide 50g by 18g/mol).
ΔH(v)=the molar heat of vaporization (in this case 40.7kJ/mol).
q=the heat that must be absorbed
q=2.778mol×40.7kJ/mol
q=113.1kJ
Therefore the water needs to absorb 1.13×10²kJ.
I hope this helps. Let me know if anything is unclear.
Answer:
renewable energy sources such as solar and wind DONT emit carbon dioxide and other greenhouse gases that contribute to global warming
Explanation:
Answer : The volume of 4.9 M 
stock solution used to prepare the solution is, 12.24 ml
Solution : Given,
Molarity of aqueous solution = 1.20 M = 1.20 mole/L
Volume of aqueous solution = 50.0 ml = 0.05 L
(1 L = 1000 ml)
Molarity of stock solution = 4.9 M = 4.9 mole/L
Formula used :
where,
= Molarity of aqueous solution
= Molarity of stock solution
= Volume of aqueous solution
= Volume of stock solution
Now put all the given values in this formula, we get the volume of stock solution.
By rearranging the term, we get
Therefore, the volume of 4.9 M stock solution used to prepare the solution is, 12.24 ml
