The density has been given as the mass of the substance per volume of the solution. The mass of citric acid in the bottle has been 1.22 grams.
<h3>What is percent mass?</h3>
Percent mass can be given as the mass of substance in the total mass of the solution.
The volume of the face serum has been 250 mL, and the density is 0.979 g/mL.
The mass of face serum in the bottle has been:

The total mass of face serum has been 244.75 grams.
The percent mass of citric acid in face serum is 0.5%. This states the presence of 0.5-gram citric acids in 100 grams sample.
The mass of citric acid in the face serum sample is given as:

The mass of citric acid present in 250 mL serum sample has been 1.22 grams.
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Answer: In order to melt a network solid, a relatively large amount of heat is needed, sufficient to break the covalent bonds that hold the entire solid together
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B, As only are metalloids or have semimetallic properties.
Is constant (matter that has a composition that is the same everywhere)
Answer:

Explanation:
mass of Fe = 55.85 g
Molar mass of Fe = 55.85 g/mol
<u>Moles of Fe = 55.85 / 55.85 = 1</u>
mass of Cl = 106.5 g
Molar mass of Cl = 35.5 g/mol
Moles of Cl = 106.5 / 35.5 = 3
Taking the simplest ratio for Fe and Cl as:
1 : 3
The empirical formula is = 