Answer:
protons = atomic numbermass number = protons + neutronsatomic number = mass number - neutrons = 78-38 = 40
Explanation:
Atomic mass Ar => 39.948 a.m.u
39.948 g --------------- 6.02x10²³ atoms
?? g -------------------- 3.8x10²⁴ atoms
(3.8x10²⁴) x 39.948 / 6.02x10²³ => 250 g
hope this helps!
Physical......................................................
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
