Answer:
See explanation
Explanation:
The balanced redox reaction equation is;
8H+ + MnO4^- + 5Fe2+ ---------> Mn2+ + 5Fe3+ + 4H2O
Amount of KMnO4 reacted = 31.60/1000 * 0.05120 = 1.62 * 10^-3 moles
From the reaction equation;
1 mole of MnO4^- reacted with 5 moles of Fe2+
1.62 * 10^-3 moles will react with 1.62 * 10^-3 moles * 5/1 = 8.1 * 10^-3 moles
Mass of Fe2+ reacted = 8.1 * 10^-3 moles * 56 g/mol
Mass of Fe2+ reacted = 0.45 g
Amount of iron in the sample = 0.45 g
Percentage of iron in the sample;
0.45 g/4.230 g * 100 = 10.6 %
Answer:
pOH = 4.8
pH = 9.2
Explanation:
Given data:
Hydrogen ion concentration = 6.3×10⁻¹⁰M
pH of solution = ?
pOH of solution = ?
Solution:
Formula:
pH = -log [H⁺]
[H⁺] = Hydrogen ion concentration
We will put the values in formula to calculate the pH.
pH = -log [6.3×10⁻¹⁰]
pH = 9.2
To calculate the pOH:
pH + pOH = 14
We will rearrange this equation.
pOH = 14 - pH
now we will put the values of pH.
pOH = 14 - 9.2
pOH = 4.8
Answer: HCl
Explanation:
calcium carbonate dissolves in HCl acid producing CO 2 gas. It will not dissolve in pure water. The Ksp for calcium carbonate in water is 3.4 x 10-9 moldm-3 which is very low. What takes place here is actually a chemical reaction:
CaCO 3 (s) + 2HCl(aq) → CaCl 2 (aq) + H 2CO 3(aq)
This reaction accounts for the solubility of the Calcium carbonate in HCl and not in pure water.
Answer:
12.
1 + 2 + 1 = 4 + 1 + 2 + 1 + 4 = 12 = 4 + 1 + 2 + 1 + 4 = 1 + 2 + 1
