The answer is 20 because in an atom no of protons equal no of electrons
Answer:
Half-reactions:
Cr³⁺ + 1e⁻ → Cr²⁺; Zn → Zn²⁺ + 2e⁻
Net ionic equation:
2Cr³⁺ + Zn → 2Cr²⁺ + Zn²⁺
Explanation:
The Cr³⁺ is reduced to Cr²⁺:
<h3>
Cr³⁺ + 1e⁻ → Cr²⁺ -Half-reaction 1-</h3>
Zn is oxidized to Zn²⁺:
<h3>
Zn → Zn²⁺ + 2e⁻ -Half-reaction 2-</h3>
Twice the reduction of Cr:
2Cr³⁺ + 2e⁻ → 2Cr²⁺
Now this reaction + Oxidation of Zn:
2Cr³⁺ + 2e⁻ + Zn → 2Cr²⁺ + Zn²⁺ + 2e⁻
<h3>2Cr³⁺ + Zn → 2Cr²⁺ + Zn²⁺ - Net ionic equation</h3>
Answer:
The concentration resulting solution = 0.350 M
Explanation:
In case of dilution , the following formula can be used -
M₁V₁ = M₂V₂
where ,
M₁ = initial concentration ,
V₁ = initial volume ,
M₂ = final concentration , i.e. , concentration after dilution ,
V₂ = final volume .
from , the question ,
M₁ = 0.85 M
V₁ = 4.12 L
M₂ = ?
V₂ = 10.0 L
Using the above formula , the molarity of the final solution after dilution , can be calculated as ,
M₁V₁ = M₂V₂
0.85 M * 4.12 L = M₂ * 10.0 L
M₂ = 0.85 M * 4.12 L / 10.0 L
M₂ = 0.350 M
I’m pretty sure it’s true