<h3>
Answer:</h3>
14 milliliters
<h3>
Explanation:</h3>
We are given;
Prepared solution;
- Volume of solution as 0.350 L
- Molarity as 0.40 M
We are required to determine the initial volume of HNO₃
- We are going to use the dilution formula;
- The dilution formula is;
M₁V₁ = M₂V₂
Rearranging the formula;
V₁ = M₂V₂ ÷ M₁
=(0.40 M × 0.350 L) ÷ 10.0 M
= 0.014 L
But, 1 L = 1000 mL
Therefore,
Volume = 14 mL
Thus, the volume of 10.0 M HNO₃ is 14 mL
Answer: option A. to decrease the solubility of the organic product in water
Explanation: sodium chloride solution act as a drying agent to remove water from an organic compound that is in solution. The salt water works to pull the water from the organic layer to the water layer,therby decreasing
2-7-1
<h3>Further explanation
</h3>
Electrons can move the shell up or down by releasing energy or absorbing energy
Excited electrons show higher electron transfer to the shell by absorbing energy
So it can be concluded that there are 2 conditions:
Ground state is the state of electrons filling shell with the lowest energy levels.
Excited state is the state of electrons which occupies a higher energy level
The state of excited electrons can be seen from the presence of electrons which do not fill the skin completely but fill the skin afterward
2-7-1
From its 8 electron configuration, filling 3 shells, 2 electrons in the firs shell, 7 electrons in the second shell and 1 electron in the third shell
the electrons in the third shell should fill the electrons in the second shell first according to Aufbau rule (lower energy shells)
Answer:
b) 3.10
Explanation:
HF ⇄ H
+ + F
Using Henderson-Hasselbalch Equation:
pH = pKa + log [A-]/[HA].
Where;
pKa = Dissociation constant = -log Ka
Hence, pKa of HF = -log 7.2 x 10^-4 = 3.14266
[A-] = concentration of conjugate base after dissociation = moles of base/total volume
= 0.15 x 0.3/0.8
= 0.05625 M
[HA] = concentration of the acid = moles of acid/total volume
= 0.10 x 0.5/0.8
= 0.0625 M
Note: <em>Total volume = 500 + 300 = 800 mL = 0.8 dm3</em>
pH = 3.14266 + log [0.05625/0.0625]
= 3.14267 + (-0.04575749056)
= 3.09691250944
<em>From all the available options below:</em>
<em>a) 2.97
</em>
<em>b) 3.10
</em>
<em>c) 3.19
</em>
<em>d) 3.22
</em>
<em>e) 3.32</em>
The correct option is b.
