Which weighs more, 5.00 g or 0.0225 mol of acetaminophen (C₈H₉O₂)?

Balance the following equation, and tell how many moles of nickel will react with 9.81 mol of hydrochloric acid.

Ni(s) + HCl(aq) → NiCl₂(aq) + H₂(g)

How many moles of NiCl₂ can be formed in the reaction of 6.00 mol of Ni and 12.0 mol of HCl?

Ni(s) + HCl(aq) → NiCl₂(aq) + H₂(g)

The reaction of ethylene oxide with water to give ethylene glycol (automobile antifreeze) occurs in 96.0% actual yield. How many grams of ethylene glycol are formed by reaction of 35.0 g of ethylene oxide? (For ethylene oxide, MW = 44.0 amu; for ethylene glycol, MW = 62.0 amu.)

The following diagram represents the reaction of A₂(red spheres) with B₂(blue spheres):

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b. How many moles of product can be made from 1.0 mol of A₂? From 1.0 mol of B₂?

Consider the balanced chemical equation: 2A + B₂ → 2AB. Given the following reaction vessel, determine the theoretical yield of product.

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Consider the balanced chemical equation: A₂ + 2 B₂ → 2 AB₂. A reaction is performed with the initial amounts of A₂ and B₂ shown in part (a). The amount of product obtained is shown in part (b). Calculate the percent yield.

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b. <IMAGE>

How many Na⁺ ions are in a mole of Na₂SO₄? How many SO₄^2- ions?

How many moles of ions are in 1.75 mol of K₂SO₄?

Caffeine has the formula C₈H₁₀N₄O₂. If an average cup of coffee contains approximately 125 mg of caffeine, how many moles of caffeine are in one cup?

The principal component of many kidney stones is calcium oxalate, CaC₂O₄. A kidney stone recovered from a typical patient contains 8.5 × 10²⁰ formula units of calcium oxalate. How many moles of CaC₂O₄ are present in this kidney stone? What is the mass of the kidney stone in grams?

Titanium metal is obtained from the mineral rutile, TiO2. The process requires multiple steps, as shown in the following reactions:

TiO₂(s) + 2 Cl₂(g) + 2 C(s) → TiCl₄(s) + 2 CO(g)

TiCl₄(s) + 2 Mg(s) → Ti(s) + 2 MgCl₂(s)

a. Write mole ratios to show the relationship between the reactants and products for each reaction.

Titanium metal is obtained from the mineral rutile, TiO2. The process requires multiple steps, as shown in the following reactions:

TiO₂(s) + 2 Cl₂(g) + 2 C(s) → TiCl₄(s) + 2 CO(g)

TiCl₄(s) + 2 Mg(s) → Ti(s) + 2 MgCl₂(s)

b. How many moles of TiO2 are needed to form one mole of titanium?

Titanium metal is obtained from the mineral rutile, TiO2. The process requires multiple steps, as shown in the following reactions:

TiO₂(s) + 2 Cl₂(g) + 2 C(s) → TiCl₄(s) + 2 CO(g)

TiCl₄(s) + 2 Mg(s) → Ti(s) + 2 MgCl₂(s)

c. How many kilograms of rutile are needed to produce 95 kg of Ti?

In Problem 6.40, hydrazine reacted with oxygen according to the following (unbalanced) equation: N₂H₄(l) + O₂(g) → NO₂(g) + H₂O(g)

a. If 75.0 kg of hydrazine are reacted with 75.0 kg of oxygen, which is the limiting reagent?

Nitrobenzene (C₆H₅NO₂) is used in small quantities as a flavoring agent or in perfumes but can be toxic in large amounts. It is produced by reaction of benzene (C₆H₆) with nitric acid:

C₆H₆(l) + HNO₃(aq) → C₆H₅NO₂(l) + H₂O(l)

a. Identify the limiting reagent in the reaction of 27.5 g of nitric acid with 75 g of benzene.

Nitrobenzene (C₆H₅NO₂) is used in small quantities as a flavoring agent or in perfumes but can be toxic in large amounts. It is produced by reaction of benzene (C₆H₆) with nitric acid:

C₆H₆(l) + HNO₃(aq) → C₆H₅NO₂(l) + H₂O(l)

b. Calculate the theoretical yield for this reaction.

When table sugar (sucrose, C₁₂H₂₂O₁₁) is heated, it decomposes to form C and H₂O.

a. Write a balanced equation for the process.

When table sugar (sucrose, C₁₂H₂₂O₁₁) is heated, it decomposes to form C and H₂O.

b. How many grams of carbon are formed by the breakdown of 60.0 g of sucrose?

Although Cu is not sufficiently active to react with acids, it can be dissolved by concentrated nitric acid, which functions as an oxidizing agent according to the following equation:

Cu(s) + 4 HNO₃(aq) → Cu(NO₃)₂(aq) + 2 NO₂(g) + 2 H₂O(l)

b. Is 35.0 g of HNO3 sufficient to dissolve 5.00 g of copper?

Ethyl alcohol is formed by enzyme action on sugars and starches during fermentation.

C₆H₁₂O₆ → 2 CO₂ + 2 C₂H₆O

If the density of ethyl alcohol is 0.789 g/mL, how many quarts can be produced by the fermentation of 100.0 lb of sugar?

Acetylsalicylic acid, the active ingredient in aspirin, is prepared from salicylic acid by reaction with acetic anhydride.

C₇H₆O₃ (salicylic acid) + C₄H₆O₃ (acetic anhydride) → C₉H₈O₄ (acetylsalicylic acid) + C₂H₄O₂ (acetic acid)

a. Calculate the theoretical yield if 47 g of salicylic acid is reacted with 25 g of acetic anhydride.

Elemental phosphorus exists as molecules of P₄. It reacts with Cl₂(g) to produce phosphorus pentachloride.

a. Write the balanced chemical equation for this reaction.

Calcium citrate, Ca(C₆H₅O₇)₂(MW = 498.5 amu), is a common dietary supplement to provide calcium needed for strong teeth and bones.

a. Look up the recommended daily dietary intake of calcium for adult men and premenopausal women.

Calcium citrate, Ca(C₆H₅O₇)₂(MW = 498.5 amu), is a common dietary supplement to provide calcium needed for strong teeth and bones.

b. What mass of calcium citrate would be needed to provide the recommended daily intake of calcium?

Obtain a bottle of aspirin and identify the amount of active ingredient (acetylsalicylic acid, C₉H₈O₄) per tablet.

a. How many moles of aspirin are in one tablet?

Lovastatin, a drug used to lower serum cholesterol.

a. Look up the molecular formula for Lovastatin and calculate the molar mass.

Pyrite, also known as fool's gold, is used commercially to produce SO₂ used in the production of paper products.

b. How many moles of SO₂ can be produced from 1.0 kg of pyrite?