Answer:
Percent mass of KNO3 in solution = 11% (Approx)
Explanation:
Given:
Mass of KNO3 = 25 grams
Mass of H2O = 200 grams
Find:
Percent mass of KNO3 in solution
Computation:
Mass of solution = 25 + 200 = 225 grams
Percent mass of KNO3 in solution = [25/225]100
Percent mass of KNO3 in solution = 11.111%
Percent mass of KNO3 in solution = 11% (Approx)
Answer:
15.3 g
Explanation:
- Fe₂O₃ (s) + 2Al (s) → 3Fe (l) + Al₂O₃ (s)
First we convert 8.0 grams of aluminum into moles, using its molar mass:
- 8.0 g Al ÷ 27 g/mol = 0.30 mol Al
Then we <u>convert 0.30 moles of aluminum into moles of aluminum oxide</u>, using the<em> stoichiometric coefficients</em>:
- 0.30 mol Al *
= 0.15 mol Al₂O₃
Finally we convert 0.15 moles of Al₂O₃ into grams, using its molar mass:
- 0.15 mol Al₂O₃ * 102 g/mol = 15.3 g Al₂O₃
1 mol Cu - 2 mol Ag
x - 0.854 mol Ag
x=0.854*1/2=0.427
0.427 mol Cu
Answer:
D. Protons ; neutrons.
Explanation:
For a given element the number of protons is fixed, but the number of neutrons differ because the element usually consist of a number of isotopes.
For example Carbon has isotopes which contain 12, 13 and 14 neutrons.
So that is why you average the number of neutrons to find the approximate atomic mass..
Sorry I'm not in chemistry but do you have any other work