All categories

2 years ago

The mass percent of solute in a solution containing 3.73 g KBr dissolved in 131 g of H2O is:

Chemistry

1 answer:

Elina [12.6K]2 years ago

7 0

$\huge \underbrace \mathfrak \red{Answer}$

28%

Explanation:

mass of solute(KBr) = 3.73g

mass of solvent(H2O) = 131g

mass of solution = mass of solute + mass of solvent

= 3.73 + 131

= 134.73g

$\sf \large {mass \: percentage = \frac{mass \: of \: solute}{mass \: of \: solvent} \times 100} \\ \\ \sf mass \: percentage = \frac{3.73}{134.73} \times 100 \\ \\ \sf mass \: percentage = 0.028 \times 100 \\ \\ \sf mass \: percentage = 28\%$

You might be interested in

When atoms gain electrons, they can become larger, because the addition of an electron increases electrostatic repulsion.

astra-53 [7]

Answer:True

Explanation: An anion has a larger radius than a neutral atom because it gains valence electrons. There are added electron/electron repulsions in the valence shell that expand the size of the electron cloud, which results in a larger radius for the anion.

hit the crown for me pls :)

Have a great day

6 0

2 years ago

3.5g of a Certain compound X, known to be made of carbon, hydrogen, and perhaps oxygen, and to have a molecular molar mass of 15

shutvik [7]

Answer:

C₅H₁₀O₅

Explanation:

1. Calculate the mass of each element in 2.78 mg of X.

(a) Mass of C

$\text{Mass of C} = \text{5.13 g CO}_{2}\times \dfrac{\text{12.01 g C}}{\text{44.01 g }\text{CO}_{2}}= \text{1.400 g C}$

(b) Mass of H

$\text{Mass of H} = \text{2.10 g H$_{2}$O}\times \dfrac{\text{2.016 g H}}{\text{18.02 g H$_{2}$O}} = \text{0.2349 g H}$

(c) Mass of O

Mass of O = 3.5 - 1.400 - 0.2349 = 1.87 g

2. Calculate the moles of each element

$\text{Moles of C = 1400 mg C}\times\dfrac{\text{1 mmol C}}{\text{12.01 mg C }} = \text{116.6 mmol C}\\\\\text{Moles of H = 234.9 mg H} \times \dfrac{\text{1 mmol H}}{\text{1.008 mg H}} = \text{233.1 mmol H}\\\\\text{Moles of O = 1870 mg O} \times \dfrac{\text{1 mmol O}}{\text{16.00 mg O}} = \text{116 mmol O}$

3. Calculate the molar ratios

Divide all moles by the smallest number of moles.

$\text{C: } \dfrac{116.6}{116.6}= 1\\\\\text{H: } \dfrac{233.1}{116.6} = 1.999\\\\\text{O: } \dfrac{116}{116.6} = 1.00$

4. Round the ratios to the nearest integer

C:H:O = 1:2:1

5. Write the empirical formula

The empirical formula is CH₂O.

6. Calculate the molecular formula.

EF Mass = (12.01 + 2.016 + 16.00) u = 30.03 u

The molecular formula is an integral multiple of the empirical formula.

MF = (EF)ₙ

$n = \dfrac{\text{MF Mass}}{\text{EF Mass }} = \dfrac{\text{150 u}}{\text{30.03 u}} = 5.00 \approx 5$

MF = (CH₂O)₅ = C₅H₁₀O₅

The molecular formula of X is C₅H₁₀O₅.

8 0

4 years ago

3. How much power is required to pull a sled if you use 60j of work in secound?

JulijaS [17]

Answer:

The answer is 60W

Power = Work done/ time

time = 1 second

Work done = 60J

Power = 60/1

= 60W

Hope this helps.

3 0

3 years ago

How many kilograms of oseltamivir would be needed to treat all the people in a city with a population of 400000 people if each p

madam [21]

Answer:

300 kg

Explanation:

The number of people in the city, p = 400,000

The number of capsules of oseltamivir each person consumes per day, n = 2 capsules

The number of days each person consumes the oseltamivir capsules, t = 5 days

The mass of oseltamivir in each capsule, m = 75 mg

The mass of oseltamivir needed to treat all the people in the city, M, is given as follows;

M = n·t·m·p

∴ M (in milligrams) = (2 × 5 × 75 × 400,000) mg = 300,000,000 mg

1,000,000 mg = 1 kg

∴ 300,000,000 mg = 300 kg

The mass of oseltamivir needed to treat all the people in the city, M = 300 kg

3 0

3 years ago

What is true about the structure or function of the plasma membrane?

den301095 [7]

Answer: hi theree, the answer is c. the processes of endocytosis and exocytosis occur here

hope this helps, have a good day :)

Explanation:

5 0

3 years ago