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3 years ago

What is the answer to...

Chemistry

1 answer:

adoni [48]3 years ago

8 0

Answer: short answer short 0.65 / 5.37

15% NaOH by mass is 15g of NaOH in (100-15)g of solution.

No. Of moles of NaOH in solution = 0.65

No of moles of Water in solution = 4.72

Mole Fraction =

(

(Moles of Solvent)

(Moles Of Solute)+(Moles of Solvent)

)

(

(Moles of Solvent)

Total Number Of Moles

)

= 0.65 / 5.37

= 0.121

Explanation:

Hope this helped

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Answer:

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Explanation:

Step 1:

Data obtained from the question. This include the following:

van 't Hoff factor (i) = 1 (since the compound is non-electrolyte)

Mass of compound = 33.2g

Volume = 250mL

Osmotic pressure (Π) = 1.2 atm

Temperature (T) = 25ºC = 25ºC + 273 = 298K

Gas constant (R) = 0.0821 atm.L/Kmol

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Step 2:

Determination of the molarity of the compound.

The molarity, M of the compound can be obtained as follow:

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Divide both side by 0.0821 x 298

M = 1.2 / (0.0821 x 298)

M = 0.049mol/L

Step 3:

Determination of the number of mole of compound in the solution. This can be obtain as follow:

Molarity = 0.049mol/L

Volume = 250mL = 250/1000 = 0.25L

Mole of compound =..?

Molarity = mole /Volume

0.049 = mole / 0.25

Cross multiply

Mole = 0.049 x 0.25

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Step 4:

Determination of the molar mass of the compound. This is illustrated below:

Mole of the compound = 0.01225 mole.

Mass of the compound = 33.2g

Molar mass of the compound =.?

Mole = Mass /Molar Mass

0.01225 = 33.2/Molar Mass

Cross multiply

0.01225 x molar mass = 33.2

Divide both side by 0.01225

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<u>Explanation:</u>

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where,

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Putting values in above equation, we get:

$\log (2.7\times 10^{-14})=\log (1.7\times 10^{-5})-\frac{273,300}{2.303\times 8.314\times T}\\\\T=1622K$

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