<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 %.
In the crystallization process the solid compound is dissolved in the solvent at elevated temperature and the crystallize product obtained by slow cooling of the solution. Here the solubility of acetanilide at 100°C is 1g per 20mL of water. Thus to dissolve 500mg of acetanilide at high temperature that is 100°C we need 10mL of water.
Now at 25°C after the re-crystallization there will be some amount of dissolve acetanilide. Which can be calculated as- 185mL of water is needed to dissolve 1g or 1000mg of acetanilide at 25°C. Thus in 10mL of water there will be 
gmg of acetanilide.
B) Tellurium is a metalloid. Metalloids in some classifications are also or alternatively called “semi-metals.”
<h2>ANSWER OF EACH PART ARE GIVEN BELOW</h2>
Explanation:
A)
We know, each mole contains 
atoms.
It is given that mass of one oxygen atom is m= 
.
Therefore, mass of one mole of oxygen, 
.
Putting value of n and 
,
B)
Given,
Mass of water in glass=0.050 kg = 50 gm.
From above part mass of one mole of oxygen atoms = 16.0 gm.
Therefore, number of mole of oxygen equivalent to 50 gm oxygen
LEARN MORE :
Avogadro's number
brainly.com/question/12902286
