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
Answer:
there are two significant figures is the number 8400
Explanation:
Continental drift is the movement of Earth’s continents over long periods of time. An evidence for this is that some continents look like puzzle pieces that can fit together, such as South America and Africa. Another evidence is that fossils of the same type have been found in different continents, far apart - suggesting that the two continents once were joined. Another evidence is that identical rocks were found at both sides of the Atlantic Ocean by Alfred Wegener, the main developer of the continents drift theory.