If a liter of solution is needed, how many grams of ethanol, C2H6O will be added when a scientist creates a 0.25 molal solution?

Chemistry

1 answer:

Dafna11 [192]4 years ago

5 0

Answer:

11.52g of ethanol

Explanation:

Molality is an unit of concentration defined as ratio between moles of solute (In this case, ethanol) and kg of solvent.

As solvent is water, 1 liter of water weights 1kg.

That means to create a 0.25molal solution it is necessary to have 0.25 moles of ethanol.

Molar weight of ethanol (C₂H₆O) is:

C: 12.01g/mol × 2 = 24.02g/mol

H: 1.01g/mol × 6 = 6.06g/mol

O: 16g/mol × 1 = 16g/mol

24.02g/mol + 6.06g/mol + 16g/mol = 46.08g/mol

As you need 0.25 moles, there is necessary to weight:

0.25 moles × (46.08g/mol) = <em>11.52g of ethanol</em>

You might be interested in

Neon has 2 isotopes. Neon-20 has a mass of 19:992 amu and

Alenkinab [10]

Answer:

20.0928.

Explanation:

The average atomic mass is (90 * 19.992 + 10* 21) / 100

= 20.0928.

6 0

3 years ago

What is the mass percentage of carbon in 5.000 G of sucrose

Crank

17) 8.4 / 20 x 100

18) 20 . 0.5150

19) 6,50% because (as you said) the law of definite proportions states that regardless of the amount, a compound is always composed of the same elements in the same proportion by mass

3 0

3 years ago

Read 2 more answers

The solubility of copper chloride at 20 °C is 73 g/100 g of water. Kiera adds 100 g of copper chloride to 100 g of water and sti

OLEGan [10]

Answer:

$m_{undissolved}=27g$

Explanation:

Hello there!

In this case, according to the given information of the solubility of copper chloride, as the maximum amount of this salt one can dissolve without having a precipitate, we infer that since just 73 grams are actually dissolved, the following amount will remain solid as a precipitate:

$m_{undissolved}=100g-73g\\\\m_{undissolved}=27g$