Answer:
d. 12.3 grams of Al2O3
Explanation:
Based on the reaction:
4Al + 3O2 → 2Al2O3
<em>Where 4 moles of Al reacts in excess of oxygen to produce 2 moles of aluminium oxide.</em>
<em />
To solve this question we must find the moles of Aluminium. With these moles we can find the moles of aluminium oxide using the reaction:
<em>Moles Al -Molar mass: 26.9815g/mol-</em>
6.50g * (1mol / 26.9815g) = 0.241 moles Al
<em>Mass Al₂O₃ -Molar mass: 101.96g/mol-</em>
0.241 moles Al * (2 mol Al2O3 / 4 mol Al) = 0.120 moles Al2O3
0.120 moles Al2O3 * (101.96g / mol) =
12.3g of Al2O3 are produced.
Right answer is:
<h3>d. 12.3 grams of Al2O3
</h3>
Answer:
2.15 mg of uranium-238 decays
Explanation:
For decay of radioactive nuclide-
where N is amount of radioactive nuclide after t time, 
is initial amount of radioactive nuclide and 
is half life of radioactive nuclide
Here 
, 
and 
So,
so, N = 2.446 mg
mass of uranium-238 decays = (4.60-2.446) mg = 2.15 mg
Answer:
b. colloid
Explanation:
Colloids are solutions that are going to have a solute and a solvent, but the size of the particles are bigger than in a solution that is clear. that is the reason that it looks blurred because the particles are bigger.
In the other hand, these particles of the solute are big, but not so big and heavy as in a suspension, so they are not going to precipitate in the bottom.
The movement of the particles are called Brownian movement, and they are the responsible to avoid to settle down at the bottom of the recipient.
Answer:
1: due to difference in reactivity and melting point
2 during the reaction both combine with oxygen in this case magnesium remain solid but some potassium vaporise
