Answer:
The water in the hydrate (referred to as "water of hydration") can be removed by heating the hydrate. When all hydrating water is removed, the material is said to be anhydrous and is referred to as an anhydrate.
Explanation:
Answer: The answer would be minerals. Synthetics are made by men, and shouldn't be found in the earth Vitamins are organic Cement is a mixture of an organic compounds and rarely found in nature.
Answer:

Explanation:
They gave us the masses of two reactants and asked us to determine the mass of the product.
This looks like a limiting reactant problem.
1. Assemble the information
We will need a chemical equation with masses and molar masses, so, let's gather all the information in one place.
Mᵣ: 239.27 32.00 207.2
2PbS + 3O₂ ⟶ 2Pb + 2SO₃
m/g: 2.54 1.88
2. Calculate the moles of each reactant

3. Calculate the moles of Pb from each reactant

4. Calculate the mass of Pb

1 L ---------- 1000 mL
274 L ------- ??
274 x 1000 / 1 => 2,740 mL
hope this helps!