Answer:
SeCl₆ < SeF₂ < SeO₂
Explanation:
(A) SeO₂
The central atom has 2 bond pairs and 1 lone pair. The molecule is bent shaped which has an angle of 120°.
(B) SeCl₆
The central atom has 6 bond pairs and 0 lone pair. The geometry is octahedral in which the equatorial bonds has an angle of 90° and axial bond has an angle of 90°.
(C) SeF₂
The central atom has 2 bond pairs and 2 lone pairs. The geometry is bent shape which has an angle of approximately 105.5°.
The order is:
<u>SeCl₆ < SeF₂ < SeO₂</u>
Answer:
33.3 g AlCl3
Explanation:
First:
You need a balanced chem equation.
2Al + 3Cl2 --->2AlCl3
So now you use this to set up train track method which helps us cancel out the units. Also we dont care about chlorine because it is excess.
6.73g Al x 1mol Al/26.98g Al x 2mol AlCl3/2molAl x 133.34g AlCl3/1molAlCl3
= 33.3 g AlCl3
Answer:
Na₂CO₃•H₂O
Explanation:
After it is heated, the remaining mass is the mass of sodium carbonate.
30.2 g Na₂CO₃
Mass is conserved, so the difference is the mass of the water:
35.4 g − 30.2 g = 5.2 g H₂O
Convert masses to moles:
30.2 g Na₂CO₃ × (1 mol Na₂CO₃ / 106 g Na₂CO₃) = 0.285 mol Na₂CO₃
5.2 g H₂O × (1 mol H₂O / 18.0 g H₂O) = 0.289 mol H₂O
Normalize by dividing by the smallest:
0.285 / 0.285 = 1.00 mol Na₂CO₃
0.289 / 0.285 = 1.01 mol H₂O
The ratio is approximately 1:1. So the formula of the hydrate is Na₂CO₃•H₂O.
