How many molecules are in each sample? a. 6.5 g H₂O c. 22.1 g O₂ d. 19.3 g C₈H₁₀

How many molecules (or formula units) are in each sample? a. 85.26 g CCl₄ b. 55.93 kg NaHCO₃ c. 119.78 g C₄H₁₀ d. 4.59×10⁵ g Na₃PO₄

Calculate the mass (in g) of each sample. a. 5.94×10²⁰ SO₃ molecules b. 2.8×10²² H₂O molecules c. 1 glucose molecule (C₆H₁₂O₆)

Calculate the mass (in g) of each sample. a. 4.5×10²⁵ O₃ molecules

Calculate the mass (in g) of each sample. b. 9.85×10¹⁹ CCl₂F₂ molecules c. 1 water molecule

A sugar crystal contains approximately 1.8×10¹⁷ sucrose (C₁₂H₂₂O₁₁) molecules. What is its mass in mg?

A salt crystal has a mass of 0.12 mg. How many NaCl formula units does it contain?

Calculate the mass percent composition of carbon in each carbon-containing compound. a. CH₄ b. C₂H₆

Calculate the mass percent composition of carbon in each carbon-containing compound. c. C₂H₂

Calculate the mass percent composition of carbon in each carbon-containing compound. d. C₂H₅Cl

Calculate the mass percent composition of nitrogen in each nitrogen-containing compound. a. N₂O b. NO

Calculate the mass percent composition of nitrogen in each nitrogen-containing compound. c. NO₂

Most fertilizers consist of nitrogen-containing compounds such as NH₃, CO(NH₂)₂, NH₄NO₃, and (NH₄)₂SO₄. Plants use the nitrogen content in these compounds for protein synthesis. Calculate the mass percent composition of nitrogen in CO(NH₂)₂.

Iron in the earth is in the form of iron ore. Common ores include Fe₂O₃ (hematite), Fe₃O₄ (magnetite), and FeCO₃ (siderite). Calculate the mass percent composition of iron for each of these iron ores. Which ore has the highest iron content?

Copper(II) fluoride contains 37.42% F by mass. Calculate the mass of fluorine (in g) in 55.5 g of copper(II) fluoride.

Silver chloride, often used in silver plating, contains 75.27% Ag by mass. Calculate the mass of silver chloride required to plate 155 mg of pure silver.

The iodide ion is a dietary mineral essential to good nutrition. In countries where potassium iodide is added to salt, iodine deficiency (or goiter) has been almost completely eliminated. The recommended daily allowance (RDA) for iodine is 150 mg/day. How much potassium iodide (76.45% I) should you consume if you want to meet the RDA?

The American Dental Association recommends that an adult female should consume 3.0 mg of fluoride (F^-) per day to prevent tooth decay. If the fluoride is consumed in the form of sodium fluoride (45.24% F), what amount of sodium fluoride contains the recommended amount of fluoride?

Write a ratio showing the relationship between the molar amounts of each element for each compound. (See Appendix IIA for color codes.) (a)

Write a ratio showing the relationship between the molar amounts of each element for each compound. (See Appendix IIA for color codes.) (b)

Determine the number of moles of hydrogen atoms in each sample. a. 0.0885 mol C₄H₁₀ b. 1.3 mol CH₄

Determine the number of moles of hydrogen atoms in each sample. c. 2.4 mol C₆H₁₂

Determine the number of moles of hydrogen atoms in each sample. d. 1.87 mol C₈H₁₈

Determine the number of moles of oxygen atoms in each sample. a. 4.88 mol H₂O₂ b. 2.15 mol N₂O c. 0.0237 mol H₂CO₃ d. 24.1 mol CO₂

Calculate mass (in grams) of sodium in 8.5 g of each sodium containing food additive. a. NaCl (table salt) b. Na₃PO₄ (sodium phosphate) c. NaC₇H₅O₂ (sodium benzoate) d. Na₂C₆H₆O₇ (sodium hydrogen citrate)

Calculate the mass (in kilograms) of chlorine in 25 kg of each chlorofluorocarbon (CFC). a. CF₂Cl₂ c. C₂F₃Cl₃ d. CF₃Cl

Calculate the mass (in kilograms) of chlorine in 25 kg of each chlorofluorocarbon (CFC). b. CFCl₃

How many fluorine atoms are present in 5.85 g of C₂F₄?

How many bromine atoms are present in 35.2 g of CH₂Br₂?

A chemist decomposes samples of several compounds; the masses of their constituent elements are listed. Calculate the empirical formula for each compound. a. 1.651 g Ag, 0.1224 g O b. 0.672 g Co, 0.569 g As, 0.486 g O c. 1.443 g Se, 5.841 g Br