A sample of an ore of iron, hematite, is 70% Fe2O3. How much iron is there in 5 kilograms of the ore?

Answer in units of g.

To find out how much iron is present in 5 kilograms of the ore, we need to calculate the weight of Fe2O3 in the given sample and then convert it to iron (Fe).

1. Start by finding the weight of Fe2O3 in the ore:
a) The ore is 70% Fe2O3, which means that 70% of the weight of the ore is Fe2O3.
b) Therefore, the weight of Fe2O3 in 5 kilograms of the ore is (70/100) * 5 kilograms.

2. Next, convert the weight of Fe2O3 to the weight of iron (Fe):
a) In Fe2O3, there are 2 iron atoms (Fe) for every molecule of Fe2O3.
b) Hence, to convert the weight of Fe2O3 to Fe, we need to multiply it by the molar mass ratio of iron in the two compounds.
c) Iron (Fe) has a molar mass of 55.845 g/mol, and Fe2O3 has a molar mass of 159.69 g/mol.
d) So, the weight of iron (Fe) is obtained by multiplying the weight of Fe2O3 by (2 * (55.845 / 159.69)).

3. Calculate the final answer:
Multiply the weight of Fe (from step 2) by 1000 to convert it to grams.

Now, let's perform the calculations:

Weight of Fe2O3 = (70/100) * 5 kg
Weight of Fe = (2 * (55.845 / 159.69)) * Weight of Fe2O3
Weight of Fe in grams = Weight of Fe * 1000 g

Using these steps, you can now substitute the values and calculate the final answer.

To calculate the amount of iron in the ore, we can use the percentage of iron content and the mass of the ore. Here's how we can do it step-by-step:

Step 1: Convert the percentage of iron content to decimal form:
Percentage of iron content = 70%
Iron content in decimal form = 70% / 100% = 0.7

Step 2: Calculate the mass of iron in 5 kilograms of the ore:
Mass of the ore = 5 kilograms
Mass of iron = Mass of the ore * Iron content
Mass of iron = 5 kilograms * 0.7

Step 3: Convert the mass of iron to grams:
Since the answer should be in grams, we need to convert the mass of iron from kilograms to grams. Since 1 kilogram = 1000 grams, we can multiply the mass of iron by 1000.
Mass of iron in grams = Mass of iron * 1000

Now, let's plug in the numbers and calculate:
Mass of iron = 5 kilograms * 0.7 = 3.5 kilograms

Mass of iron in grams = 3.5 kilograms * 1000 = 3500 grams

Therefore, there is 3500 grams of iron in 5 kilograms of the ore.