All categories

5 days ago

In how many grams of water should 25.31 g of potassium nitrate (kno3) be dissolved to prepare a 0.1982 m solution?

Chemistry

2 answers:

alisha [964]5 days ago

8 0

Result: The amount of water required to dissolve the specified quantity of potassium nitrate is 1263.1g.

Clarification:

To determine the mass of solvent required for a specified molality, we utilize the formula:

$\text{Molality of solution}=\frac{m_{solute}\times 1000}{M_{solute}\times W_{solvent}\text{ (in grams)}}$

where,

Molality of the solution = 0.1982 m

$m_{solute}$ = Mass of solute $(KNO_3)$ = 25.31 g

$M_{solute}$ = Molar mass of solute $(KNO_3)$ = 101.1 g/mol

$W_{solvent}$ = Mass of solvent (water) =?

Substituting values into the equation yields:

$0.1982=\frac{25.31\times 1000}{101.1\times \text{Mass of water}}\\\\\text{Mass of water}=\frac{25.31\times 1000}{101.1\times 0.1982}=1263.1g$

Consequently, the necessary mass of water to dissolve the provided amount of potassium nitrate is 1263.1g.

lions [985]5 days ago

6 0

Solution:

Molality measures the concentration of a solute in a solution, defined by the amount of solute per specific mass of solvent.

Thus,

Molality = moles of solute / kg of solvent.

Therefore, kg of solvent = moles of solute / molality.

moles of solute = mass / molar mass

= 25.31 g / 101.1 g/mole

= 0.2503 mole.

kg of solvent = 0.2503 mole / 0.1982 m

= 1.263 kg

= 1263 g.

This is the final answer.

You might be interested in

Consider butter (density= 0.860 g/mL) and sand (density= 2.28 g/mL). If 1.00 mL of butter were mixed with 1.00 mL of sand and mi

Anarel [852]

The mixture’s density is 1.57 g/cm³.

Step 1: Determine the mass of the butter.

$\text{Mass} = \text{1.00 cm}^{3 } \times \frac{\text{0.680 g} }{\text{1 cm}^{3 }} = \text{0.860 g}\\$

Step 2: Determine the mass of the sand.

$\text{Mass} = \text{1.00 cm}^{3 } \times \frac{\text{2.28 g} }{\text{1 cm}^{3 }} = \text{2.28 g}\\$

Step 3: Determine the density of the mixture.

Total mass = 0.860 g + 2.28 g = 3.14 g.

Total volume = 1 cm³ + 1 cm³ = 2 cm³

$\text{Density} = \frac{\text{mass}}{\text{volume}} = \frac{\text{3.14 g} }{\text{2 cm}^{3 }} = \textbf{1.57 g/cm}{^{3}\\$

6 0

1 day ago

A sample of neon gas at STP is allowed to expand into an evacuated vessel. What is the sign of work for this process?

Alekssandra [968]

Answer:

The work done in this process will be considered Negative.

Explanation:

The energy transferred by the system to the environment is negative

Therefore, if work is done on the system, it is labeled as positive. Conversely, when work is done by the system, it is regarded as negative.

In this scenario, the argon gas is expanding, and the work is exerted by the system into the surroundings (container), making the sign Negative.

Thus, the result for the work pertaining to this process will carry a Negative sign.

3 0

9 days ago

The next 3 questions will walk you through using the Henderson-Hasselbalch equation for the following question. For each step pr

lions [985]

Response:

The pKa value is 13.0.

Clarification:

pKa + pKb = 14

For trimethylamine, Kb = 6.3 × $10^{-5}$

Calculating pKb: pKb = - log (6.3 × $10^{-5}$ )

= 1.0

Thus, pKa = 14 - pKb = 14 - 1.0

pKa = 13.0

Verification: The typical range for pKa in weak acids is from 2 to 13.

8 0

5 days ago

How many protons neutrons and electrons are there in a neutral atom of 43k (potassium-43)?

castortr0y [923]

Answer:

Protons: 19

Neutrons: 25

Electrons: 19

Explanation:

Protons:

The atomic number determines the number of protons in an atom. Consequently, with Potassium's atomic number being 19, it contains 19 protons.

Neutrons:

The formula to find neutrons is:

# of Neutrons = Atomic Mass - # of Protons

Given:

Atomic Mass = 43

# of Protons = 19

Thus,

# of Neutrons = 43 - 19

# of Neutrons = 24

Electrons:

In a neutral atom, the quantity of electrons matches that of protons. Therefore, a neutral Potassium atom with 19 protons must equally have 19 electrons.

3 0

18 hours ago

In living organisms, C-14 atoms disintegrate at a rate of 15.3 atoms per minute per gram of carbon. A charcoal sample from an ar

lions [985]

Answer:

The result is "4,241.17 years"

Explanation:

The disintegration rate for C-14 atoms is indicated in $15.3 \frac{atoms}{min-g}$