There should be 3 valence electrons surrounding the aluminum ion
B An enclosed pendulum is not acted on by air resistence or gravity. Plus, pendulum's in clocks are electronic (I think) so that's why it keeps moving back in forth. (at least i think so)
Moles Fe₂O₃ produced : 1.16 moles
<h3>Further explanation</h3>
Given
2.32 moles of iron
Required
moles of Fe2O3
Solution
The reaction coefficient in a chemical equation shows the mole ratio of the reacting compounds (reactants and products)
Reaction
4 Fe + 3 O₂ ⇒ 2 Fe₂O₃
From the equation, mol ratio Fe : mol Fe₂O₃ = 4 : 2, so mol Fe₂O₃ :
= 2/4 x mol Fe
= 2/4 x 2.32
= 1.16 moles
When the solutions are diluted in half:
So [ Ca+2] = 0.001/2 = 0.0005 M
[SO4-2]= 0.01/2 =0.005
when Q = [Ca2+][SO4-2]
so by substitution:
Q = 0.0005*0.005 = 2.5x10^-6
by comparing with Ksp value
So when Q < Ksp
∴ the answer is no precipitation will occur, as the solution is unsaturated.
