Answer:
78.04g of 0.448 moles must be added
Explanation:
Using H-H equation we can find the pH of the buffer:
pH = pKa + log [A⁻] / [HA]
<em>Where pH is the pH of the buffer = 7.2</em>
<em>pKa = 7.1</em>
<em>[A⁻] = [K₂HPO₄]</em>
<em>[HA] = [KH₂PO₄]</em>
<em />
Replacing:
7.2 = 7.1 + log [K₂HPO₄] / [KH₂PO₄]
0.1 = log [K₂HPO₄] / [KH₂PO₄]
1.2589 = [K₂HPO₄] / [KH₂PO₄] <em>(1)</em>
<em />
And as the concentration of the buffer is:
1M = [K₂HPO₄] + [KH₂PO₄] <em>(2)</em>
<em></em>
Replacing (2) in (1):
1.2589 = 1M - [KH₂PO₄] / [KH₂PO₄]
1.2589 [KH₂PO₄] = 1M - [KH₂PO₄]
2.2589 [KH₂PO₄] = 1M
[KH₂PO₄] = 0.44M
And [K₂HPO₄] = 0.56M
In 800mL = 0.8L:
0.8L * (0.56mol / L) = 0.448 moles K₂HPO₄. The mass is -Molar mass K₂HPO₄: 174.2g/mol-:
0.448 moles * (174.2g / mol) =
<h3>78.04g of 0.448 moles must be added</h3>
Answer:
Hey!I will try to help with the ones I know.
solubility is a means of comparing the extent to which different solutes can dissolve in a particular solvent at a definite temperature.
A saturated solution of a solute at a particular temperature is one which contains as much solute as it can dissolve at that temperature in the presence of undissolved solute particles....
This is what I know I hope it helps you
> 2,000
mL of a 5.0 × 10–5% (w/v) sucrose solution
5.0 × 10–3
g/mL * 2000 mL * (1 mol / 342.30 g) = 0.0292 mol
<span>
> 2,000 mL of a 5.0 ppm sucrose solution</span>
5 grams /
1000000 mL * 2000 mL* (1 mol / 342.30 g) = 0.0000292 mol
<span>
> 20 mL of a 5.0 M sucrose solution </span>
5.0 M *
0.020 L = 0.1 mol
Answer:
<span>2,000 mL
of a 5.0 ppm sucrose solution</span>
Answers:
Most of the world’s energy comes from what three sources?
Oil, coal, and gas.
These energy sources are called <u>fossil</u> fuels and they are <u>non-renewable</u> resources.
Fuel type: oil
How it's formed: from the remains of ancient marine organisms
Its uses: transportation, industrial power, heating and lighting, lubricants, petrochemical industry, and use of by-products
Fule type: coal
How it's formed: when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial
Its uses: electricity generation, metal production, cement production, chemical production, gasification, and other industrial uses
Fuel type: gas
How it's formed: decomposed organic matter mixed with mud, silt, and sand on the seafloor
Its uses: heating & cooling buildings, cooking foods, fueling vehicles, and electricity generation
Explanation:
The given data is as follows.
Moles of propylene = 100 moles, = 100 J/mol K
= 300 K, = 800 K
= 2 , = 0.02
Therefore, the assumptions will be as follows.
- The given system is very well insulated.
- The work is done on the system because the given process is a compression process.
- Assume that there is no friction so, work done on the system is equal to the heat energy liberated.
= W
Putting the given values into the above formula as follows.
= W
W =
= J
= 5 MJ
Hence, this shows that a minimum of 5 MJ work needs to be done.
Since, work is very less. Hence, it will not compress the given system to 800 K and 0.02 .