<u>Answer:</u> The percent composition of
in taconite is 37.6 %.
<u>Explanation:</u>
We are given:
Mass of taconite pellets = 1 ton = 907185 g (Conversion factor: 1 ton = 907185 g)
Mass of iron produced = 545 lb = 247212 g (Conversion factor: 1 lb = 453.6 g )
We know that:
Molar mass of iron = 55.85 g/mol
Molar mass of
= 231.53 g/mol
1 mole of
contains 3 moles of iron atom and 4 moles of oxygen atom
(3 × 55.85) = 167.55 g of iron is produced from 231.53 grams of 
So, 247212 grams of iron will be produced from =
of 
To calculate the percentage of
in taconite, we use the equation:

Mass of taconite = 907185 g
Mass of
= 341611.43 g
Putting values in above equation, we get:

Hence, the percent composition of
in taconite is 37.6 %.
Answer: 0.156 mol
Explanation:
To find the moles of 17.2 g K₂S, we need to know the molar mass to convert.

Answer: The 3rd and 6th bullet point is the quantitative data.
Explanation: Quantitative data is expressed by NUMBERS and Qualitative data is expressed by WORDS. The 3rd and 6th one is correct because they both use numbers to compare how much time hummingbirds spent feeding on nectar.
The photoelectric effect occurs when light shines on a metal. ... Light of any frequency will cause electrons to be emitted.