.42; 3.4 divided by 8.1 is about .42
Answer:
2
Step-by-step explanation:
A. Moles before mixing
<em>Beaker I:
</em>
Moles of H⁺ = 0.100 L × 0.03 mol/1 L
= 3 × 10⁻³ mol
<em>Beaker II:
</em>
Beaker II is basic, because [H⁺] < 10⁻⁷ mol·L⁻¹.
H⁺][OH⁻] = 1 × 10⁻¹⁴ Divide each side by [H⁺]
[OH⁻] = (1 × 10⁻¹⁴)/[H⁺]
[OH⁻] = (1 × 10⁻¹⁴)/(1 × 10⁻¹²)
[OH⁻] = 0.01 mol·L⁻¹
Moles of OH⁻ = 0.100 L × 0.01 mol/1 L
= 1 × 10⁻³ mol
B. Moles after mixing
H⁺ + OH⁻ ⟶ H₂O
I/mol: 3 × 10⁻³ 1 × 10⁻³
C/mol: -1 × 10⁻³ -1 × 10⁻³
E/mol: 2 × 10⁻³ 0
You have more moles of acid than base, so the base will be completely neutralized when you mix the solutions.
You will end up with 2 × 10⁻³ mol of H⁺ in 200 mL of solution.
C. pH
[H⁺] = (2 × 10⁻³ mol)/(0.200 L)
= 1 × 10⁻² mol·L⁻¹
pH = -log[H⁺
]
= -log(1 × 10⁻²)
= 2
Answer:
Explanation:
Let assume that the missing aqueous solution of 4-chlorobutanoic acid = 0.76 M
Then, the dissociation of 4-chlorobutanoic acid can be expressed as:
⇄
+ 
The ICE table can be computed as:
⇄
+ 
Initial 0.76 - -
Change -x +x +x
Equilibrium 0.76 - x x x
![K_a = \dfrac{[\mathsf{C_3H_6ClCO_2^-}] [\mathsf{H^+}]}{\mathsf{[C_3H_6ClCO_2H ]}}](https://tex.z-dn.net/?f=K_a%20%3D%20%5Cdfrac%7B%5B%5Cmathsf%7BC_3H_6ClCO_2%5E-%7D%5D%20%5B%5Cmathsf%7BH%5E%2B%7D%5D%7D%7B%5Cmathsf%7B%5BC_3H_6ClCO_2H%20%5D%7D%7D)
![K_a = \dfrac{[x] [x]}{ [0.76-x]}](https://tex.z-dn.net/?f=K_a%20%3D%20%5Cdfrac%7B%5Bx%5D%20%5Bx%5D%7D%7B%20%5B0.76-x%5D%7D)
where:

![3.02*10^{-5} = \dfrac{x^2}{ [0.76-x]}](https://tex.z-dn.net/?f=3.02%2A10%5E%7B-5%7D%20%3D%20%5Cdfrac%7Bx%5E2%7D%7B%20%5B0.76-x%5D%7D)
however, the value of x is so negligible:
0.76 -x = 0.76
Then:


x = 0.00479 M
∴
0.00479 M
= (0.76 - 0.00479) M
= 0.75521 M
Finally, the percentage of the acid dissociated is;
= ( 0.00479 / 0.76) × 100
= 0.630 M
Answer: The standard cell potential (E∘) for the reaction
is -0.121 V
Explanation:
The reaction is:
Relation between standard Gibbs free energy and equilibrium constant follows:

where,
= Standard Gibbs free energy = ?
R = Gas constant = 
T = temperature = 298 K
K= equilibrium constant = 
Putting values in above equation, we get:

To calculate standard Gibbs free energy, we use the equation:

Where,
n = number of electrons transferred = 1
F = Faradays constant = 96500 C
= standard cell potential = ?
Putting values in above equation, we get:



Thus standard cell potential (E∘) for the reaction
is -0.121 V