Answer:
The most important ore of aluminum is<u> Bauxite.</u>
And its chemical formula is
.
Explanation:
Bauxite is the most important ore of Aluminium from which Aluminium is extracted. Bauxite is a rock and composed of Aluminium bearing mineral.
And its chemical formula is
.
It contains Gibbsite, Bohmite and Diaspore along with iron.
It is a soft material with somewhat white to grey to reddish brown in colour.
It has an earthy lustre and low specific gravity.
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Answer:

Explanation:
From the question, we have been asked to find the molarity of FeCl2 having a volume of 450 mL,
We have been provided with 225 g which is proportional to 1.8 moles.
We know that molarity of any solution should be in mol/L.
1 mole contained in 1 L means it has a molarity of 1 mol/L
Let's convert 450 mL to Litres which is,

= 0.450 L
Thus,
1 mole is contained in 1L
x moles are contained in 0.450 L
Hence,
x mole/molarity = {1 mole x 1 L}/{0.450 L}
= 4 mol/L
Therefore 4 mol/L is the molar concentration.
<u>Answer:</u> The mass percent of hydrogen in methyl acetate is 8 %
<u>Explanation:</u>
The given chemical formula of methyl acetate is 
To calculate the mass percentage of hydrogen in methyl acetate, we use the equation:

Mass of hydrogen = (6 × 1) = 6 g
Mass of methyl acetate = [(3 × 12) + (6 × 1) + (2 × 16)] = 74 g
Putting values in above equation, we get:

Hence, the mass percent of hydrogen in methyl acetate is 8 %
Definitely Calcium Chloride.
All the others are covalent.