Answer:
3 moles of CO are needed
Explanation:
Given data:
Number of moles of CO used = ?
Mass of Fe produced = 112 g
Solution:
Chemical equation:
Fe₂O₃ + 3CO → 2Fe + 3CO₂
Number of moles of Fe:
Number of moles = mass/ molar mass
Number of moles = 112 g/ 55.85 g/mol
Number of moles = 2.00 mol
Now we will compare the moles of iron and CO.
Fe : CO
2 : 3
Thus, 3 moles of CO are needed.
2. CuCl₂·2H₂O is limiting reactant.
Chemical reaction: 3CuCl₂·2H₂O + 2Al → 3Cu + 2AlCl₃ + 6H₂O. m(Al) = 0,5 g.

The metal component of the given compound, CrCl3, is chromium. The number of moles per 1 g of chromium is calculated through the equation below,
n = (1 g Cr)(1 mol Cr/51.996 g Cr)
n = 0.0192 mol Cr(3 electrons/1 mol Cr)
n = 0.0577 e-
Determine the number in charge by multiplying with Faraday's constant,
C = (0.0577 mol Cr)((1 F/1 mol e-)(96485 C/ 1F)
C = 5,566.87 C
Then, calculate time by dividing the charge with the current,
t = 5566.87 C/1.5 A
t = 3711.25 minutes
t = 61.84 hours
<span><em>Answer: 61.84 hours</em></span>
Answer:
A = B < D < C
C - S
Cl - Cl
F ← H
Si → O
Explanation:
The polarity of a bond increases with the increase in the difference in electronegativity. The dipole moment is represented with an arrow pointing the more electronegative atom.
A: carbon-sulfur
C - S
ΔEN = |EN(C) - EN(S)| = |2.5 - 2.5| = 0
B: chlorine - chlorine
Cl - Cl
ΔEN = |EN(Cl) - EN(Cl)| = |3.0 - 3.0| = 0
C: fluorine – hydrogen
F ← H
ΔEN = |EN(F) - EN(H)| = |4.0 - 2.1| = 1.9
D: silicon - oxygen
Si → O
ΔEN = |EN(Si) - EN(O)| = |1.8 - 3.5| = 1.7
The order of increasing polarity is A = B < D < C.