Answer:
pH = 13.09
Explanation:
Zn(OH)2 --> Zn+2 + 2OH- Ksp = 3X10^-15
Zn+2 + 4OH- --> Zn(OH)4-2 Kf = 2X10^15
K = Ksp X Kf
= 3*2*10^-15 * 10^15
= 6
Concentration of OH⁻ = 2[Ba(OH)₂] = 2 * 0.15 = 3 M
Zn(OH)₂ + 2OH⁻(aq) --> Zn(OH)₄²⁻(aq)
Initial: 0 0.3 0
Change: -2x +x
Equilibrium: 0.3 - 2x x
K = Zn(OH)₄²⁻/[OH⁻]²
6 = x/(0.3 - 2x)²
6 = x/(0.3 -2x)(0.3 -2x)
6(0.09 -1.2x + 4x²) = x
0.54 - 7.2x + 24x² = x
24x² - 8.2x + 0.54 = 0
Upon solving as quadratic equation, we obtain;
x = 0.089
Therefore,
Concentration of (OH⁻) = 0.3 - 2x
= 0.3 -(2*0.089)
= 0.122
pOH = -log[OH⁻]
= -log 0.122
= 0.91
pH = 14-0.91
= 13.09
Answer:
False
Explanation:
Half life is the time period at which the concentration of the radioactive substance in decay reduced to half.
<u>Thus, if the hydrogen-3 has gone 2 half lives, it means that it has first reduced to its half and then again the half of what it was, i.e. 1/4</u>
Thus, after two successive half-lives, the concentration must be 1/4 of the initial concentration and hence, the statement is false.
Answer:
<h3>The answer is 7.85 g/mL</h3>
Explanation:
The density of a substance can be found by using the formula
volume = final volume of water - initial volume of water
volume = 13.91 - 12 = 1.91 mL
We have
We have the final answer as
<h3>7.85 g/mL</h3>
Hope this helps you
Answer:
0.054 mol O
Explanation:
<em>This is the chemical formula for acetic acid (the chemical that gives the sharp taste to vinegar): CH₃CO₂H. An analytical chemist has determined by measurements that there are 0.054 moles of carbon in a sample of acetic acid. How many moles of oxygen are in the sample?</em>
<em />
Step 1: Given data
- Chemical formula of acetic acid: CH₃CO₂H
- Moles of carbon in the sample: 0.054 moles
Step 2: Establish the appropriate molar ratio
According to the chemical formula, the molar ratio of C to O is 2:2.
Step 3: Calculate the moles of oxygen in the sample
We will use the molar ratio to determine the moles of oxygen accompanying 0.054 moles of carbon.
0.054 mol C × (2 mol O/2 mol C) = 0.054 mol O
P = pressure, V = volume, T = absolute temperature k = constant.
