Answer:
28.9%
Explanation:
Let's consider the following balanced equation.
2 FeS₂ + 11/2 O₂ ⇒ Fe₂O₃ + 4 SO₂
We can establish the following relations:
- The molar mass of Fe₂O₃ is 159.6 g/mol
- 1 mole of Fe₂O₃ is produced per 2 moles of FeS₂
- 1 mole of Fe is in 1 mole of FeS₂
- The molar mass of Fe is 55.84 g/mol
The amount of Fe in the sample that produced 0.516 g of Fe₂O₃ is:

The percent of Fe in 1.25 g of the ore is:

Answer:
It is the distance between two compressions or two rarefactions.
Explanation:
Answer:
the anwser isn't in the choices
Explanation:
H=MC(change of temp.)
M=mass of water=250g
C=specific heat of water = 4.186 j/g
change in temperature is 121-40= 81
H= 250x4.186x81=84766.5J
This process is called aerobic respiration.
The reaction between hydrogen (H2) and fluorine (F2) is given below,
H2 + F2 ---> 2HF
One mole of both hydrogen and fluorine yields to 2 moles of hydrogen fluoride. This can also be expressed as, 2 grams of hydrogen and 38 grams of fluorine will form 40 grams of hydrogen fluoride. From the given, only 20 grams of HF is formed with 19 g of it being fluorine. Thus, the percentage fluorine of the compound formed is 95%.