Answer:
Mass = 157.5 g
Explanation:
Given data:
Mass of CO needed = ?
Mass of Fe formed = 209.7 g
Solution:
Chemical equation:
3CO + F₂O₃ → 2Fe + 3CO₂
Number of moles of Fe:
Number of moles = mass/ molar mass
Number of moles = 209.7 g/ 55.85 g/mol
Number of moles = 3.75 mol
Now we will compare the moles of iron and carbon monoxide.
Fe : CO
2 : 3
3.75 ; 3/2×3.75 = 5.625 mol
Mass of CO:
Mass = number of moles × molar mass
Mass = 5.625 mol × 28 g/mol
Mass = 157.5 g
<span>the atomic mass of nitrogen is 14. There is 1 nitrogen atom in the molecule so the percentage of N is :
14/35 x100% = 40%</span>
Answer: 27 is A and 28 is C.
Explanation: I’ll explain 28 but not 27 because that’s just definitions.
In CuSO4 there is a Cu, an S, and 4 O molecules. Add them up you get 6.
Answer:
2 elements
Explanation:
Octane is composed of carbon and hydrogen atoms.
It takes 33.4 s for the concentration of A to fall to one-fourth of its original value.
A <em>half-life</em> is the time it takes for the concentration to fall to half its original value.
Assume the initial concentration is 1.00 mol/L. Then,
The concentration drops to one-fourth of its initial value in two half-lives.
∴ Time = 2 × 16.7 s = 33.4 s
