Answer:
Mass fraction = 0.08004
Mole fraction = 0.0377
Explanation:
Given, Mass of NaOH = 8.70 g
Mass of solution = 8.70 + 100 g = 108.70 g
= 0.08004
Molar mass of NaOH = 39.997 g/mol
The formula for the calculation of moles is shown below:
Thus,

Given, Mass of water = 100 g
Molar mass of water = 18.0153 g/mol
The formula for the calculation of moles is shown below:
Thus,

So, according to definition of mole fraction:
Answer:

Explanation:
Data:
p₁ = 694.9 mmHg; V₁ = 3.463 L
p₂ = ?; V₂ = 5.887 L
Calculation:

I'm not sure but I think it is A. image one has the most spread out particles like a gas, and b has closer together particles like a liquid or solid. since there are no choices that say A=gass and B=solid, so I am guessing it is answer A.
Answer:
The concentration of KOH is 0.186 M
Explanation:
First things first, we need too write out the balanced equation between HBr and KOH.
This is given as;
KOH (aq) + HBr (aq) → KBr (aq) + H2O (l)
From the reaction above, we can tell that it takes 1 mole of KOH to react with 1 mole of HBr.
We use the acid base formular in calculating unknown concentrations. This is given as;

where;
Ca = Concentration of acid
Va = Volume of acid
Cb = Concentration of base
Vb = Volume of base
na = Number of moles of acid
nb = Number of moles of base
KOH is the base and HBr is acid.
Hence;
Ca = 0.225
Va = 35
Cb = ?
Vb = 42.3
na = 1
nb = 1
Making Cb subject of formular we have;

Cb = (0.225 * 35 * 1) / (42.3 * 1)
Cb = 0.186 M