We need two pieces of information to calculate the reduction of the
vapor pressure of the solvent in a solution containing a nonvolatile
nonelectrolyte:
<span>
<span>The mole fraction of the
nonvolatile solute, Xsolute, in the solution.</span>
<span>The vapor pressure of the
pure solvent, Psolv.</span>
</span>
Psoln = Psolvent (1- Xsolute)
Xsolute = (100g /342.3 g/ mol) / ( 100g
/342.3 g/ mol) + (250 g/ 18 g/ mol)
X solute = 0.0206
P soln = (23.8 mmHg) (1- 0.0206)
Psoln = 23.31 mmg Hg
<span> </span>
<h3>
Answer:</h3>
48.95% (m/v)
<h3>
Explanation:</h3>
From the question we are given;
- Mass of solute, NaCl is 186 g
- Volume of the solvent, water as 3.80 L or 380 mL
We are required to calculate the mass volume percent of solution;
How do we calculate the mass volume percent of a solution?
- To calculate the mass volume percent, we use the formula,
Mass volume percent = (mass of solute in g/Volume of solvent in mL) 100
= (186 g ÷ 380 mL)100
= 48.95%
Therefore, the mass volume percent of a NaCl solution is 48.95% (m/v).
Density is defined as mass/volume (or m/v).
So,
(126.0 g)/(12.5 cm^3)= 10.08 g/cm^3
If your teacher requires correct significant figures, the answer is 10.1 g/cm^3.
If not, the first answer is fine.
Answer:
Explanation:
Convert molecules to moles:
1 mole of NaNO₃= 6.02 x 10^23 molecules of NaNO₃
7.3 x10^24/(6.02 x 10^23)=12mol NaNO₃
Find molar mass:
NaNO₃=1 mole of Na and 1mole of N and 3mole of O
Find grams:
14.01g x 12= 168.12 g of N