PLEASE HELP ME ASAPPPP

1 answer:

7 0

Answer: 100.95°C

Explanation:

1) The increase of the boiling point of a solution is a colligative property and its value is:

ΔTb = m × Kb × i

2) i is the Van't Hoof constant ans for non ionic solute is 1.

3) m is the molality

m = moles of solute / Kg of solvent

moles of solute = mass in grams / molar mass

molar mass of C₂H₅OH = 2 × 12.0 g/mol + 2 × 1.0 g/mol + 16.0 g/mol + 1.0 g/mol = 43.0 g/mol


moles of solute = 20.0 g / 43.0 g/mol = 0.465 mol


m = 0.465 mol / 0.250 kg = 1.86 m

3) Kb is the molal boiling constant of the solvent.

For water Kb = 0.512 °C / mol

4) ΔTb = 1.86m × 1 × 0.512 °C / mol = 0.95°C.

5) Boiling temperature

Tb = 100°C + 0.95°C = 100.95°C

You might be interested in

Which statement about atmospheric pressure near Earth’s surface is true?

valentinak56 [21]

I think the correct answer from the choices listed above is option B. The statement that is true about the atmospheric pressure near Earth’s surface would be that it decreases as you move away from Earth’s surface. Pressure decreases with increasing altitude. Hope this answers the question.

6 0

3 years ago

Read 2 more answers

Please HELP, ASAP! Homework due tomorrow and I need some help.

sweet-ann [11.9K]

Ions are atoms with a charge other than zero. In a neutral atom, the number of protons (positively charged particles) in the nucleus equals the number of electrons orbiting the nucleus.
Atoms can gain or lose electrons (not protons) resulting in a net charge other than zero. Atoms which lose electrons (usually metals) become positively charges, and atoms which gain electrons (usually nonmetals) become negatively charged.

3 0

4 years ago

Give the electronic configuration of carbon atom.

zimovet [89]

Answer:

1s2 2s2 2p2

Explanation:

it has 6 electrons in two energy levels so the sub levels are 1s, 2s and 2p

4 0

3 years ago

How do the atmosphere conditions near the beginning of Precambrian time contrast with the atmosphere conditions that are present

babunello [35]

The early precambrian atmosphere consisted primarily of nitrogen and carbon dioxide with almost no oxygen.

Today, the atmosphere contains about 20% oxygen, less carbon dioxide and similar amounts of nitrogen. 

Photosynthetic green-leaf plants and trees are largely responsible for the change, converting carbon dioxide to oxygen.

5 0

3 years ago

Aspirin sun thesis Green Chemistry and Assime the aspirin is prepared by the following reaction and that 10.09. of salicylic aci

klemol [59]

Answer: The percentage yield of aspirin is 38.02 %.

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)