Answer:
28
Explanation:
electron = atomic number - charge(if the charge is positive and addition if the charge is negative)
electron = 30 - 2
electron = 28
1) Reaction: 3Mg + N₂ → Mg₃N₂.
m(Mg) = 0,225 g
n(Mg) = 0,225 g ÷ 24,3 g/mol = 0,009 mol.
n(Mg) : n(N₂) = 3 : 1
n₁(N₂) = 0,003 mol.
n₂(N₂) = 0,5331 ÷ 28 = 0,019 mol.
n₃(N₂) = 0,019 mol - 0,003 mol = 0,016, m(N₂) = 0,016mol·28g/mol=0,4467g.
or simpler: m(N₂) = 0,225 g + 0,5331 - 0,3114 g = 0,4467 g.
2) Answer is: 6 <span>of fluorine atoms are combined with one uranium atom.
</span>m(U) = 209 g.
m(F) = 100 g.
n(U) = m(U) ÷ M(U)
n(U) = 209 g ÷ 238 g/mol.
n(U) = 0,878 mol.
n(F) = m(F) ÷ M(F)
n(F) = 5,263 mol
n(U) : n(F) = 0,878 mol : 5,263 mol /:0,878.
n(U) : n(F) = 1 : 6.
n - amount of substance
<h2>Answer:</h2>
<u>In dry climates, rates of evaporation exceed precipitation</u>
<h2>Explanation:</h2>
Evaporation is an important process in the global water cycle. Sunrays hits the surface of water or land and causes water to change state from a liquid to a gas. This is what we call evaporation. When evaporation occurs, at the same time precipitation occurs in the atmosphere which is the water falling from the clouds as rain, freezing rain, sleet, snow, or hail. As the rate of evaporation increases, the rate of precipitations increases too because both are connected to each other.
Answer:
The limiting reactant is the ZnS
Explanation:
The equation for this reaction is:
2 ZnS + 3O₂ = 2 ZnO + 2 SO₂
2 moles of zinc sulfure reacts with 3 moles of oxygen.
Then, 1.72 mol of ZnS would react with ( 1.72 .3)/2 = 2.58 moles of O₂
If we have 3.04 moles, then the oxygen is the reactant in excess.
Let's confirm, the ZnS as the limiting reactant.
3 moles of oxygen react with 2 moles of sulfure.
Then, 3.04 moles of O₂ would react with (3.04 .2) / 3 = 2.02 moles of ZnS
We have 1.72 moles of Zn S and it is not enough for the 2.02 moles that we need, for the reaction.
