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2 years ago

Which liquid has the highest vapor pressure at 75°C?

Chemistry

1 answer:

Temka [501]2 years ago

4 0

Answer:

1) Ethanol

Explanation:

If we will have interactions we will need more energy to break them in order to go from liquid to gas. If we need more energy, therefore, the temperature will be higher.

In this case, we can discard the propanone because this molecule don't have the ability to form hydrogen bonds. (Let's remember that to have hydrogen bonds we need to have a hydrogen bond to a heteroatom, O, N, P or S).

Then we have to analyze the hydrogen bonds formed in the other molecules. For ethanol, we will have only 1 hydrogen bond. For water and ethanoic acid, we will have 2 hydrogen bonds, therefore, we can discard the ethanol.

For ethanoic acid, we have 2 intramolecular hydrogen bonds. For water we have 2 intermolecular hydrogen bonds, therefore, the strongest interaction will be in the ethanoic acid.

The closer boiling point to the 75ºC is the ethanol (boiling point of 78.8 ºC) therefore these molecules would have enough energy to break the hydrogen bonds and to past from liquid to gas.

You might be interested in

Sodium hydride reacts with excess water to produce aqueous sodium hydroxide and hydrogen gas:NaH (s) H2O (l) → NaOH (aq) H2 (g)A

Anuta_ua [19.1K]

NaH(s)+ H2O (l)=>NaOH(aq)+H2(g)

You want to calculate the mass of NaH, I assume. Otherwise, the question isn't clear. It simply says calculate the mass(??)

So, calculate the moles of H2 gas that satisfy the conditions of 982 ml at 28ºC and 765 torr. But you must subtract the vapor pressure of water at 28º to get the actual pressure of the H2 gas. So, the actual conditions are 982 ml (0.982 L) and 301 K and 765-28 = 737 torr.

PV = nRT

n = PV/RT = (737 torr)(0.982 L)/(62.4 L-torr/Kmol)(301 K)

n = 0.0385 moles H2

moles NaH needed = 0.0385 moles H2 x 1 mole NaH/mole H2 = 0.0385 moles NaH required

mass of NaH needed = 0.0385 moles x 24 g/mole = 0.925 g NaH

Brainliest Please :)

7 0

3 years ago

Read 2 more answers

A gaseous mixture composed of 20% CH4, 30% C2H4, 35% C2H2, and 15% C2H20. What is the average molecular weight of the mixture? a

Semenov [28]

Answer: The correct answer is Option d.

Explanation:

We are given:

Mass percentage of $CH_4$ = 20 %

So, mole fraction of $CH_4$ = 0.2

Mass percentage of $C_2H_4$ = 30 %

So, mole fraction of $C_2H_4$ = 0.3

Mass percentage of $C_2H_2$ = 35 %

So, mole fraction of $C_2H_2$ = 0.35

Mass percentage of $C_2H_2O$ = 15 %

So, mole fraction of $C_2H_2O$ = 0.15

We know that:

Molar mass of $CH_4$ = 16 g/mol

Molar mass of $C_2H_4$ = 28 g/mol

Molar mass of $C_2H_2$ = 26 g/mol

Molar mass of $C_2H_2O$ = 48 g/mol

To calculate the average molecular mass of the mixture, we use the equation:

$\text{Average molecular weight of mixture}=\frac{_{i=1}^n\sum{\chi_im_i}}{n_i}$

where,

$\chi_i$ = mole fractions of i-th species

$m_i$ = molar masses of i-th species

$n_i$ = number of observations

Putting values in above equation:

$\text{Average molecular weight}=\frac{(\chi_{CH_4}\times M_{CH_4})+(\chi_{C_2H_4}\times M_{C_2H_4})+(\chi_{C_2H_2}\times M_{C_2H_2})+(\chi_{C_2H_2O}\times M_{C_2H_2O})}{4}$

$\text{Average molecular weight of mixture}=\frac{(0.20\times 16)+(0.30\times 28)+(0.35\times 26)+(0.15\times 42)}{4}\\\\\text{Average molecular weight of mixture}=6.75$

Hence, the correct answer is Option d.

3 0

3 years ago

A major disadvantage of a corporation is the

Nikitich [7]

A major disadvantage of a corporation is the double taxation of the corporation's income and of dividends paid to shareholders.
Corporations end up paying taxes twice. The corporation pays tax when it shows a profit. Secondly the corporation pays tax when it pays out dividends to its shareholders. Sole proprietorships and partnerships are taxed as owners of the business. The owners of a corporation are taxed individually from the corporation. The advantage of this is that the owners of a corporation are not taxed on the corporation's profit.

7 0

3 years ago

A solution is formed by mixing 0.400 mol NaOH

leonid [27]

Answer:

The correct answer is m= mol solute kg soivent

Explanation:

Molality is a measure of concentration, which indicates the moles of solute (in this case sodium hydroxide) in 1kg of solvent .

In this case:

0,800 kg water-----0,400 mol NaOH

1 ,000 kg water ---x=(1 ,000 kg water x 0,400 mol NaOH)/0,800 kg water

x=0,5 mol NaOH---> The solution is 0,5 molal (0,5 m)

6 0

3 years ago

Galvanized nails are iron nails that have been plated with zinc to prevent rusting. The relevant reaction is

umka21 [38]

Answer:

50. 5mol

Explanation:

The mass of Zinc required = 3.30 kg = 3300 grams

The relation between moles and mass is:

$moles=\frac{mass}{atomicmass}$

Atomic mass of Zinc = 65.38g/mol

$molesofZinc=\frac{3300}{65.38}$

$molesofzinc=50.47mol$

The answer to three significant figures will be 50.5 mol

3 0

2 years ago