Answer:
None of the given options
Explanation:
Let's go case by case:
A. No matter the volume, the concentration of Fe(NO₃)₃ (and thus of [Fe³⁺] as well) is 0.050 M.
B. We can calculate the moles of Fe₂(SO₄)₃:
- 0.020 M * 0.80 L = 0.016 mol Fe₂(SO₄)₃
Given that there are two Fe⁺³ moles per Fe₂(SO₄)₃ mol, in the solution we have 0.032 moles of Fe⁺³. With that information in mind we <u>can calculate [Fe⁺³]</u>:
- 0.032 mol Fe⁺³ / 0.80 L = 0.040 M
C. Analog to case A., the molar concentration of Fe⁺³ is 0.040 M.
D. Similar to cases A and C., [Fe⁺³] = 0.010 M.
Thus none of the given options would have [Fe⁺³] = 0.020 M.
Answer:
I think the answer should be B. Number of valence electrons
Molarity is defined as the number of moles of solute in 1 L of solution
molar mass of Ni(NO₃)₂ - 182.7 g/mol
number of moles of Ni(NO₃)₂ - 5.80 g/ 182.7 g/mol = 0.0317 mol
number of moles in 500 mL - 0.0317 mol
therefore number of moles in 1000 mL - 0.0317 mol / 500 mL x 1000 mL/L
molarity of the solution is - 0.0634 M