Quiz 7 CSHS

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Which of the following statements are true and are steps needed to answer the following question: How many atoms of Calcium are in 7.81 g of CaF₂. (all numbers are rounded to 3 significant digits). You may use scratch paper and the following template if you wish.

There are 40.1 g of Calcium in one mole of Calcium.

There are 19.0 g. of Fluorine in 1 mole of Fluorine

To find the molar mass of Calcium Fluoride, we would take 1 x 40.1 + 2 x 19.0

The molar mass of Calcium Fluoride is 78.1

To find the moles of Calcium Fluoride in 7.81 g of CaF₂we would divide 7.81 / 78.1

There are 0.100 moles of Calcium Fluoride in 7.81 g of Calcium Fluoride

To find the number of atoms in 7.81 g of CaF₂ we would multiply 0.100 moles x 6.02 x 10²³ atoms/mole

The number of atoms in 7.81 g of CaF₂is 6.02 x 10²⁴ atoms.

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Stavka koja se može prevući		Odgovarajuća stavka
Molar Mass of CO₂		12.0 g
Mass of Oxygen in one mole of CO₂		16.0 g
Mass of 0.75 moles of Carbon Dioxide		32.0 g
Molar Mass of Oxygen		44.0 g
Molar Mass of Carbon		33.0 g

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146 g Glutamate x .41 = 59.9 g C (rounded to 3 significant digits)

146 g Glutamate x .055 = 8.03 g H (rounded to 3 significant digits)

146 g Glutamate x .095 = 13.9 g N (rounded to 3 significant digits)

146 g Glutamate x .44 = 64.2g O (rounded to 3 significant digits)

59.9 g C / (12.0 g/mol) = 4.99 mol, which rounds to 4

8.03 g H / (1.01 g/mol) = 7.95 mol, which rounds to 8

13.9 g N / (14.0 g/mol) =.993 mol, which rounds to 9

64.2 g O / (16.0 g/mol) =4.01 mol, which rounds to 4

The Molecular formula of Glutamate is C₅H₈NO₄

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