Answer:
C = 18.29 g
Explanation:
Given data:
Mass of beryllium needed = ?
Mass of nitrogen = 18.9 g
Solution:
Chemical equation:
3Be + N₂ → Be₃N₂
now we will calculate the number of moles of nitrogen:
Number of moles = mass/molar mass
Number of moles = 18.9 g/ 28 g/mol
Number of moles = 0.675 mol
Now we will compare the moles of nitrogen and Be from balance chemical equation.
N₂ : Be
1 : 3
0.675 : 3/1×0.675 = 2.03 mol
Number of moles of Be needed are 2.03 mol.
Mass of Beryllium:
Mass = number of moles × molar mass
Mass = 2.03 mol × 9.01 g/mol
Mass = 18.29 g
Electrons might be the answer
Missing questions:
<span>a) How many milliliters of acid are in the resulting mixture?
b) What percentage of the resulting mixture is acid?
a) V</span>₁ = 35 ml.
ω₁ = 18% = 0,18.
V₂ = 90 ml.
ω₂ = 68% = 0,68.
V(acid) = V₁ · ω₁ + V₂ · ω₂.
V(acid) = 35 ml · 0,18 + 90 ml · 0,68 = 67,5ml.
b) ω(acid) = 67,5 ml ÷ (35 ml + 90 ml).
ω(acid) = 54%.
The rate of evaporation would decrease because of
the formation of bonds between the soap and the water.
So, no. Regular water evaporates faster than soapy water
