Answer:
x=3
Step-by-step explanation:
minus 3x on both sides
after you've subtracted 3x from both sides you then need to minus 12 from both sides
Last step is going to be dividing by 2 and you should get the answer of 3
In the balanced reaction
2 Fe + O₂ → 2 FeO
2 moles of iron (Fe) react with 1 mole of molecular oxygen (O₂) to produce 2 moles of iron oxide (FeO). The ratio of Fe to FeO is 1-to-1, so if one starts with 42.4 mol of Fe, one will end up with the same amount of FeO, 42.4 mol.
Look up the molar mass of Fe and O:
• Fe = 55.845 g/mol
• O = 15.999 g/mol
Then the molar mass of FeO is approximately 71.835 g/mol, and so the mass of 42.4 mol of FeO is
(42.4 mol) × (71.835 g/mol) ≈ 3050 g
A (A right triangle with a side length of 5 and hypotenuse with length \sqrt{74})
I’m pretty sure the answer would be B