Answer:
0.159 M
Explanation:
convert from mL to L then use the equation:
M1V1 = M2V2
rearrange to find M2


Answer:
a. 342.9 kJ of heat are absorbed.
Explanation:
Calculation of the moles of
as:-
Mass = 20.00 g
Molar mass of
= 17.031 g/mol
The formula for the calculation of moles is shown below:
Thus,

Given that:- 
It means that 1 mole of
undergoes reaction and absorbs 1168\ kJ of heat
So,
1168 mole of
undergoes reaction and absorbs
of heat
<u>Amount of heat absorbed = + 342.9 KJ</u>
It is melting point process
Answer:
83.24 mmHg.
Explanation:
- <em>The vapor pressure of the solution (Psolution) = (Xmethanol)(P°methanol).</em>
where, Psolution is the vapor pressure of the solution,
Xmethanol is the mole fraction of methanol,
P°methanol is the pure vapor pressure of methanol.
- We need to calculate the mole fraction of methanol (Xmethanol).
<em>Xmethanol = (n)methanol/(n) total.</em>
where, n methanol is the no. of moles of methanol.
n total is the total no. of moles of methanol and urea.
- We can calculate the no. of moles of both methanol and urea using the relation: n = mass/molar mass.
n of methanol = mass/molar mass = (56.9 g)/(32.04 g/mol) = 1.776 mol.
n of urea = mass/molar mass = (7.38 g )/(60.06 g/mol) = 0.123 mol.
∴ Xmethanol = (n)methanol/(n) total = (1.776 mol)/(1.776 mol + 0.123 mol) = 0.935.
<em>∴ Psolution = (Xmethanol)(P°methanol)</em> = (0.935)(89.0 mmHg) =<em> 83.24 mmHg.</em>