Nickel Ni Uchemya.weebly.com/uploads/2/8/9/7/28974683/stoichiometry.pdf · 2019-04-20 · used and amounts of products formed by a chemical reaction. Stoichiometry is based on the

Germanium

32

Ge 72.61

Nickel

28

Ni 58.693

Uranium

92

U 238.029

Sulfur

16

S 32.066

Stoichiometry Worksheets

Chemistry worksheets, Stoichiometry

pg. 1 http://chemya.weebly.com

Mole Ratios Stoichiometry: The study of quantitative relationships between the amounts of reactants

used and amounts of products formed by a chemical reaction.

Stoichiometry is based on the law of conservation of mass. Recall that the law states that

matter is neither created nor destroyed in a chemical reaction. In any chemical reaction, the

amount of matter present at the end of the reaction is the same as the amount of matter

present at the beginning. Therefore, the mass of the reactants equals the mass of the products.

4Fe(s) 3O2(g) 2Fe2O3(s)

iron oxygen iron(III) oxide

4 atoms Fe 3 molecules O2 2 formula units Fe2O3

4 mol Fe 3 mol O2 2 mol Fe2O3

223.4 g Fe 96.00 g O2 319.4 g Fe2O3

319.4 g reactants 319.4 g products

1) In the following interactions, determine the number of moles of each component of the

reaction.

a) 2PbO2 2PbO O2

__________ __________ __________

b) 2Fe(OH)3 Fe2O3 3H2O

__________ __________ __________

c) (NH4)2CO3 2NH3 H2O CO2

__________ __________ __________ __________

d) 4H2 Fe3O4 3Fe 4H2O

__________ __________ __________ __________

Law of conservation of mass

Molar mass ratio #𝒈

𝟏𝒎𝒐𝒍

2) conclude the molecular mass relationship of the following Elements

Molar massSubstance Molar mass Substance Molar mass Substance

N2 N H

Fe O 7g/molLi

C O2 Mg

S8 O3 Cl



3) conclude the molecular mass relationship of the following compounds

Molar massSubstance Molar mass Substance Molar mass Substance

(NH4)2CO3

CO2 18g/molH2O

Zn(NO3)2

PbO2

Fe2O3

Fe(OH)3

CH4

C3H8

4) The combustion of propane (C3H8) provides energy for heating homes, cooking food, and

soldering metal parts. Interpret the equation for the combustion of propane in terms of

representative particles, moles, and mass. Show that the law of conservation of mass is

observed.

C3H8 (g) + 5 O2 (g) 3CO2 (g) + 4 H2O(g)

1 molecule C3H8+ 5 molecules O2 3 molecules CO2 + 4 molecules H2O

1 mol C3H8+ 5 mol O2 3 mol CO2 + 4 mol H2O

moles of reactant or product × 𝑔𝑟𝑎𝑚𝑠 𝑟𝑒𝑎𝑐𝑡𝑎𝑛𝑡 𝑜𝑟 𝑝𝑟𝑜𝑑𝑢𝑐𝑡

1 𝑚𝑜𝑙 𝑟𝑒𝑎𝑐𝑡𝑎𝑛𝑡 𝑜𝑟 𝑝𝑟𝑜𝑑𝑢𝑐𝑡 = grams of reactant or product

1 mol C3H8 × 44.09 𝑔 𝐶3𝐻8

1 𝑚𝑜𝑙 𝐶3𝐻8 = 44.09 g C3H8

5 mol O2 ×32.00 𝑔 𝑂2

1 𝑚𝑜𝑙 𝑂2 = 160.0 g O2.

3 mol CO2 × 44.01 𝑔 𝐶𝑂2

1 𝑚𝑜𝑙 𝐶𝑂2 = 132.0 g CO2.

4 mol H2O × 18.02 𝑔 𝐻2𝑂

1 𝑚𝑜𝑙 𝐻2𝑂 = 72.08 g H2O

44.09 g C3H8 + 160.0 g O2 = 204.1 g reactants.

132.0 g CO2 + 72.08 g H2O = 204.1 g products.

204.1 g reactants = 204.1 g products.

The coefficients

indicate the number

of molecules.

The coefficients

also indicate the

number of moles.

The conversion factor we use to calculate mass

Calculate the mass of the reactant C3H8 .

Calculate the mass of the reactant O2

Calculate the mass of the product CO2

Calculate the mass of the product H2O

Add the masses of the reactants

the law of conservation of mass is observed

Add the masses of the products



Calculate the mass of the reactants and products in the following reactions and apply the

law of conservation of mass

5) 2PbO2 → 2PbO + O2

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6) 2Fe(OH)3 → Fe2O3 + 3H2O

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7) (NH4)2CO3 → 2NH3 + H2O + CO2

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Balance the following equations and apply the law of conservation of mass

8) H2 + O2 → H2O

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9) CH4 + O2 → CO2 + H2O

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Mole ratio A mole ratio is a conversion factor that relates the amounts in moles of any two substances in

a chemical reaction. The numbers in a conversion factor come from the coefficients of the

balanced chemical equation.

The production of ammonia (NH3) from nitrogen and hydrogen gases is an important industrial

reaction called the Haber process, after German chemist Fritz Haber.

N2(g)+3H2(g)→2NH3(g) The balanced equation can be analyzed in several ways, as shown in Figure below.

The following six mole ratios can be written for the ammonia forming reaction above.

1 mol N2

3 mol H2 ,

3 mol H2

1 mol N2 ,

1 mol N2

2 mol NH3 ,

2 mol NH3

1 mol N2 ,

2 mol NH3

3 mol H2 ,

3 mol H2

2 mol NH3

Note that the number of mole ratios you can write for a chemical reaction involving a total of

n substances is (n)(n-1). Thus, for reactions involving four and five substances, you can write

12 and 20 moles ratios, respectively.

Four substances: (4)(3) = 12 mole ratios

Five substances: (5)(4) = 20 mole ratios

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10) Determine all possible mole ratios for the following balanced chemical equations.

a) 4Al(s) + 3O2(g) → 2Al2O3(s)

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b) 3Fe(s) + 4H2O(l) → Fe3O4(s) + 4H2(g)

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c) 2HgO(s) → 2Hg(l) + O2(g)

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11) Balance the following equations and determine the possible mole ratios.

a) ZnO(s) + HCl(aq) → ZnCl2(aq) + H2O(l)

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b) butane ( C4H10 ) + oxygen → carbon dioxide + water

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Stoichiometric Calculations Mole to mole conversion In a mole ratio problem, the given substance, expressed in moles, is written first. The

appropriate conversion factor is chosen in order to convert from moles of the given substance

to moles of the unknown.

How many moles of ammonia are produced if 4.20 moles of hydrogen are reacted with an

excess of nitrogen?

12) One disadvantage of burning propane (C3H8) is that carbon dioxide (CO2) is one of the

products. The released carbon dioxide increases the concentration of CO2 in the

atmosphere. How many moles of CO2 are produced when 10.0 mol of C3H8 are burned in

excess oxygen in a gas grill?

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13) Methane and sulfur react to produce carbon disulfide (CS2), a liquid often used in the

production of cellophane.

___CH4(g) + ___ S8(s) → ___CS2(l) + ___ H2S(g)

a. Balance the equation. b. Calculate the moles of CS2 produced when 1.50 mol S8 is used.

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c. How many moles of H2S are produced?

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Known Unknown Known Mole × mole ratio

Mole Mole

H2 = 4.20 mol

mol of NH3 = ? 4.20 mol H2 ×

2 mol NH3

3 mol H2 = 2.80 mol NH3

From the

balanced

equation



14) Sulfuric acid ( H2SO4 ) is formed when sulfur dioxide (SO2 ) reacts with oxygen and water. a. Write the balanced chemical equation for the reaction.

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b. How many moles of H2SO4 are produced from 12.5 moles of SO2?

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c. How many moles of O2 are needed?

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15) If you have 9 moles of H₂, how many moles of NH₃ can you make?

N₂+3H₂→2NH₃

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2 H₂ + O₂ → 2 H₂O

16) If 8 moles of H2O are produced, how many moles of oxygen gas must be used?

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17) If 14.00 moles of H₂ were used, how many moles of water would be produced?

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18) What's the molar ratio between H₂SO₄ and H₂O

2Al(OH)₃ + 3H₂SO₄ → Al₂(SO₄)₃ + 6H₂O

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19) If you have 30 moles of S₂ , how many FS₃ moles can you make?

2F + 3S₂ → 2FS₃

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20) If you have 12 moles of NaClO₃ will produce how many moles of O₂?

2 NaClO3 → 2 NaCl + 3 O2

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21) To make 6 moles of AlCl3, how many moles of HCl would you need to start the reaction?

2Al+ 6HCl → 2AlCl₃ + 3H₂(g)

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22) How many moles of aluminum sulfate will be produced from the reaction of 3 moles of

aluminum hydroxide?

2Al(OH)₂ + 3H₂SO₄ → Al₂(SO₄)₂ + 6H₂O

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Mole to mass conversion

In a chemical reaction if we know the number of moles for a component so we can calculate

the number of moles for all the other components and using the number of moles we can

calculate the mass for all the components.

Determine the mass of sodium chloride (NaCl), commonly called table salt, produced when

1.25 mol of chlorine gas ( Cl2 ) reacts vigorously with excess sodium.

23) Sodium chloride is decomposed into the elements sodium and

chlorine by means of electrical energy. How much chlorine gas, in

grams, is obtained from the process diagrammed at right? ____________________________________________________________________________________________________________________________________

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Known Unknown Known Mole × mole ratio

Mole Mole

Moles × 𝒎𝒐𝒍𝒆𝒄𝒖𝒍𝒂𝒓 𝒎𝒂𝒔𝒔

𝟏𝒎𝒐𝒍𝒆

Mass

moles of chlorine = 1.25 mol

Cl2

mass of sodium chloride =? g

2Na(s) + Cl2(g) → 2NaCl(s)

Mole ratio: 2 mol NaCl

1 mol Cl 2

1.25 mol Cl2 × 2 mol NaCl

1 mol Cl 2 = 2.50 mol NaCl

1mlo NaCl = 58.44 g

2.50 mol NaCl × 58.44 g NaCl

1 𝑚𝑜𝑙 𝑁𝑎𝐶𝑙 = 146 g NaCl

From the

balanced

equation

From the

periodic

table



24) Titanium is a transition metal used in many alloys because it is extremely strong and

lightweight. Titanium tetrachloride (TiCl4) is extracted from titanium oxide (TiO2) using

chlorine and coke (carbon). TiO2 + C + 2Cl2 → TiCl4 + CO2

a. What mass of Cl2 gas is needed to react with 1.25 mol of TiO2?

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b. What mass of C is needed to react with 1.25 mol of TiO2?

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c. What is the mass of all of the products formed by reaction with 1.25 mol of TiO2?

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25) What is the resulting Mg magnesium mass when 2.5mol of potassium K is reacted?

MgCl2(s) + 2 K(s) → Mg(s) + 2 KCl(s) ____________________________________________________________________________________________________________________________________

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26) What is the hydrogen H2 mass resulting from the reaction of 4mol of zinc Zn?

Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g) ____________________________________________________________________________________________________________________________________

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27) How many Aluminum Al Moles are produced from the 10.87 g Silver Ag reaction?

Al(NO3)3 + 3 Ag → Al + 3 AgNO3 ____________________________________________________________________________________________________________________________________

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Mass to Moles Problems

Acetylene gas, C2H2, is used in welding, produces an extremely hot flame when it burns in pure oxygen according to the following reaction.

2 C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O(g)

28) How many moles of water (H2O) are produced when 25.0 grams of C2H2 burns completely? ____________________________________________________________________________________________________________________________________

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3 Mg + 1 Fe2O3 → 2 Fe + 3 MgO

29) How many moles of iron, Fe, are produced with 25.0 grams of magnesium, Mg? ____________________________________________________________________________________________________________________________________

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30) Laughing gas (nitrous oxide, N2O) is sometimes used as an anesthetic in dentistry.

NH4NO3(s) → N2O(g) + 2H2O(l)

a. How many moles of NH4NO3 are required to produce 33.0g of N2O? ____________________________________________________________________________________________________________________________________

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b. How many moles of water are produced with 45.0g of N2O? ____________________________________________________________________________________________________________________________________

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Known Unknown

Known Mole × mole ratio

Mole Mole

Mass × 𝟏𝒎𝒐𝒍𝒆

𝒎𝒐𝒍𝒆𝒄𝒖𝒍𝒂𝒓 𝒎𝒂𝒔𝒔

Mass

From the

balanced

equation

From the

periodic

table



Mass to Mass Problems

Ammonium nitrate decomposes to dinitrogen monoxide and water according to the following

equation.

NH4NO3(s)→N2O(g)+2H2O(l)

31) In a certain experiment, 45.7 g of ammonium nitrate is decomposed. Find the mass of each

of the products formed.

32) If 5.0 g of KClO₃ is decomposed, how many grams of KCl are produced? (3.0 g)

2KClO₃ → 2KCl + 3O₂

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Known Unknown


Mole Mole





Mass Mass

From the

balanced

equation

From the

periodic

table

From the

periodic

table

given:

45.7 g NH4NO3

molar mass of NH4NO3 =

80.06 g/mol

molar mass of N2O = 44.02

g/mol

molar mass of H2O = 18.02

g/mol

Unknown:

mass N2O =? g

mass H2O =? g

(mole ratios) 1 mol NH4NO3 = 1 mol N2O = 2 mol H2O

g NH4NO3 → mol NH4NO3 → mol 𝐍𝟐𝐎 → g 𝐍𝟐𝐎

45.7 g NH4NO3 × 1𝑚𝑜𝑙 𝑁𝐻4𝑁𝑂3

80.06 g 𝑁𝐻4𝑁𝑂3 = 0.6 mol NH4NO3

0.6mol NH4NO3 × 1 mol N2O

1𝑚𝑜𝑙 𝑁𝐻4𝑁𝑂3 = 0.6 mol N2O

0.6 mol N2O × 44.02 g N2O

1𝑚𝑜𝑙 N2O = 25.1 g N2O

g NH4NO3 → mol NH4NO3 → mol H2O → g H2O

0.6mol NH4NO3 × 2 mol H2O

1𝑚𝑜𝑙 𝑁𝐻4𝑁𝑂3 = 1.2 mol H2O

1.2 mol H2O × 18.02 g H2O

1𝑚𝑜𝑙 H2O = 20.06 g H2O

2

1

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33) How many potassium chloride grams are produced if 25 g of potassium chlorate

decompose? (15 g)

2KClO₃ → 2KCl + 3O₂

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34) How many grams of hydrogen are necessary to react completely with 50.0 g of nitrogen in

the above reaction? (10.8 g)

N₂ + 3H₂ → 2NH₃

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35) How many grams of ammonia are produced when 50.0g of nitrogen reacts with hydrogen

in the above reaction? (60.8 g)

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36) How many grams of silver chloride are produced from 5.0 g of silver nitrate reacting with

an excess of barium chloride? (4.2 g AgCl)

2AgNO₃ + BaCl₂ → 2AgCl + Ba(NO₃)₂

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37) How much BaCl₂ is necessary to react with 5.0 g of silver nitrate in the above reaction?

(3.1 g)

2AgNO₃ + BaCl₂ → 2AgCl + Ba(NO₃)₂

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LiOH + HBr → LiBr + H₂O

38) If you start with 10.0 g of LiOH, how many grams of lithium bromide will be produced?

(36.25 g)

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H₂SO₄ + 2NaOH → 2H₂O + Na₂SO₄

39) How many molecules of water are produced if 2.0 g of sodium sulfate are produced in the

above reaction? 2.41x10²⁴ molecules

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2AlCl₃ → 2Al + 3Cl₂

40) If 10.0 g of aluminum chloride are decomposed, how many molecules of Cl₂ are produced?

6.77x10²² molecules

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Number of

particles Number of

particles particles ×


𝟔.𝟎𝟐𝟐×𝟏𝟎𝟐𝟑 𝒑𝒂𝒓𝒕𝒊𝒄𝒍𝒆 moles ×

𝟔.𝟎𝟐𝟐×𝟏𝟎𝟐𝟑 𝒑𝒂𝒓𝒕𝒊𝒄𝒍𝒆



Mole Mole





Mass Mass

From the

periodic

table

From the

periodic

table

From the

balanced

equation



Limiting Reactant

In the reaction,

N2(g)+3H2(g)→2NH3(g)

One mole of N2 will react with three moles of H2 to form two moles of NH3. Now let us suppose

that a chemist was to react three moles of N2 with six moles of H2.

Hydrogen gas will be completely used up while there will be 1 mole of nitrogen gas left over

after the reaction is complete. Finally, the reaction will produce 4 moles of NH3 because that

is also two times as much as shown in the balanced equation. The overall reaction that

occurred in words:

2 mol N2 + 6 mol H2 → 4 mol NH3

All the amounts are doubled from the original balanced equation.

The limiting reactant (or limiting reagent) is the reactant that determines the amount of

product that can be formed in a chemical reaction.

The reaction proceeds until the limiting reactant is completely used up. In our example above,

the H2 is the limiting reactant.

The excess reactant (or excess reagent) is the reactant that is initially present in a greater

amount than will eventually be reacted.

In other words, there is always excess reactant left over after the reaction is complete. In the

above example, the N2 is the excess reactant.

three

moles

of N2

six

moles

of H2

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Determining the limiting reactant

sulfur dichloride is used to vulcanize rubber, a process that makes rubber harder, stronger, and less likely to become soft when hot or brittle when cold. It is produced by reacting sulfur and chlorine as follows:

S8(l) + 4Cl2(g) → 4S2Cl2(l)

41) Determine the mass (g) of S2Cl2 produced when 200.0g of S8 and 100.0g of Cl2 react.

Determine the limiting reactant, the excess reactant, the mass reacted and the excess

remaining.

given:

200.0g of S8

100.0g of Cl2

Unknown:

1. Determine the limiting

reactant

2. Mass (g) of S2Cl2

Analyze the excess reactant

3. Mass reacted

4. Excess remaining

100.0 g Cl2 × 1𝑚𝑜𝑙 𝐶𝑙2

70.91g 𝐶𝑙2 = 1.410 mol 𝐶𝑙2

200.0 g S8 × 1𝑚𝑜𝑙 𝑆8

256.5 g 𝑆8 = 0.7797 mol S8

1.410 mol 𝐶𝑙2 available

0.7797 mol 𝑆8 available =

1.808 mol 𝐶𝑙2 available

1 mol 𝑆8 available

From the balanced chemical equation each 1mol S8

need 4 moles Cl2 of but we have less amount of Cl2,

so Cl2is the limiting reactant

1.410 mol Cl2 × 4 mol 𝑆2𝐶𝑙2

4 mol 𝐶𝑙2×

135.0 g 𝑆2𝐶𝑙2

1 mol 𝑆8𝐶𝑙2 = 190.4 g

S2Cl2

1.410 mol Cl2 × 1 mol 𝑆8

4 mol 𝐶𝑙2 = 0.3525 mol S8

0.3525 mol S8 26505 g 𝑆8

1 mol 𝑆8 = 90.42 g S8

200.0 g S8 available - 90.42 g S8 needed = 109.6 g

S8 in excess

1

2

3

4



42) The reaction between solid white phosphorus (P4) and oxygen produces solid tetraphosphorus

decoxide (P4O10). This compound is often called diphosphorus pentoxide because its empirical

formula is P2O5.

a. Determine the mass of P4O10 formed if 25.0 g of P4 and 50.0 g of oxygen are combined.

b. How much of the excess reactant remains after the reaction stops?

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43) The reaction between solid sodium and iron (III) oxide is one in a series of reactions that

inflates an automobile airbag: 6Na(s) + Fe2O3(s) → 3Na2O(s) + 2Fe. If 100.0 g of Na and

100.0 g of Fe2O3 are used in this reaction, determine the following.

a. limiting reactant b. reactant in excess c. mass of solid iron produced d. mass of excess reactant that remains after the reaction is complete

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44) Photosynthesis reactions in green plants use carbon dioxide and water to produce glucose

(C6H12O6) and oxygen. A plant has 88.0 g of carbon dioxide and 64.0 g of water available

for photosynthesis.

a. Write the balanced chemical equation for the reaction. b. Determine the limiting reactant. c. Determine the excess reactant. d. Determine the mass in excess. e. Determine the mass of glucose produced

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Our bodies need vitamins, minerals, and some other elements in specific amounts to facilitate normal metabolic reactions. A lack of these substances can lead to

• Abnormalities in growth and development.

• Abnormalities in functioning of your body’s cells. ➢ Phosphorus is an essential element in living systems; phosphate groups occur regularly in

strands of DNA. ➢ Potassium is needed for proper nerve function, muscle control, and blood pressure. A diet

low in potassium and high in sodium might be a factor in high blood pressure. ➢ Vitamin B-12. Without adequate vitamin B-12, the body is unable to synthesize DNA

properly, affecting the production of red blood cells.

Why do we use excess of a reactant?

We use one of the components of the reaction in abundant quantities and often the least

expensive reactant, this to ensure that the reaction is continuous until the limiting reactant

finished as well as to increase the speed of the reaction.

A Bunsen burner in the lab where the gas is burning with oxygen. The products depend on the

amount of oxygen available to react. If the oxygen is in excess amount, the flame color is blue,

and the carbon is completely burned. In case of lack of oxygen, the carbon does not burn

completely, which turns the color of flame to yellow and accumulates black soot on the surface

of the cup.



Percent yield Most reactions never succeed in producing the predicted amount of product. Reactions do not

go to completion or yield as expected for a variety of reasons.

1) Liquid reactants and products might adhere to the surfaces of their containers or

evaporate.

2) Products other than the intended ones might be formed by competing reactions, thus

reducing the yield of the desired product.

3) Some amount of any solid product is usually left behind on filter paper or lost in the

purification process.

We can easily calculate the amount of products in a particular reaction, but the important

question is, is the quantity of products really the same as the quantity we calculated? Chemical

reactions often do not produce the same mass values that we calculate in our calculations.

Hence, we have two values for the product mass, theoretical and actual yield.

Theoretical yield: The maximum amount of product that can be produced from specific

quantities of reactants.

Actual yield: The amount of product produced when a chemical reaction occurs during a

practical experiment.

Percent yield: the ratio of the actual yield to the theoretical yield.

percent yield = (actual yield)

(theoretical yield) × 100



45) Solid silver chromate (Ag2CrO4) forms when excess potassium chromate (K2CrO4) is added

to a solution containing 0.500 g of silver nitrate (AgNO3). Determine the theoretical yield

of Ag2CrO4. Calculate the percent yield if the reaction yields 0.455 g of Ag2CrO4.

K2CrO4 + 2AgNO3 → Ag2CrO4 + 2KNO3

The answer

✓ Transfer the AgNO3 mass to the number of moles.

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✓ Using the number of moles (AgNO3), calculate the number of moles (Ag2CrO4) produced.

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✓ Using the number of moles (Ag2CrO4), calculate its mass (theoretical yield). ____________________________________________________________________________________________________________________________________

✓ Calculate the percent yield ____________________________________________________________________________________________________________________________________

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46) Aluminum hydroxide (Al(OH)3) is often present in antacids to neutralize stomach acid (HCl).

The reaction occurs as follows: Al(OH)3(s) + 3HCl(aq) → AlCl3(aq) + 3H2O(l). If 14.0 g of Al(OH)3

is present in an antacid tablet, determine the theoretical yield of AlCl3 produced when the

tablet reacts with HCl. ____________________________________________________________________________________________________________________________________

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47) Zinc reacts with iodine in a synthesis reaction: Zn + I2 → ZnI2

a. Determine the theoretical yield if 1.912 mol of zinc is used.

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b. Determine the percent yield if 515.6 g of product is recovered.

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48) When copper wire is placed into a silver nitrate solution (AgNO3), silver crystals and copper

(II) nitrate (Cu(NO3)2) solution form.

a. Write the balanced chemical equation for the reaction.

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b. If a 20.0-g sample of copper is used, determine the theoretical yield of silver.

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c. If 60.0 g of silver is recovered from the reaction, determine the percent yield of the

reaction.

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Percent Yield in the Marketplace

Sulfuric acid is an important chemical because it is a raw material used to make products such

as fertilizers, detergents, pigments, and textiles. The cost of sulfuric acid affects the cost of

many of the consumer items you use every day. The steps of the manufacturing process are

shown below.

Step 1 S8(s) + 8O2(g) → 8SO2(g)

Step 2 2SO2(g) + O2(g) → 2SO3(g)

Step 3 SO3(g) + H2O(l) → H2SO4(aq)

The first step, the combustion of sulfur, produces an almost 100% yield. The second step also

produces a high amount of products when the reaction takes place in the presence of a catalyst

and raises the temperature to 400 ° C

49) What is the catalyst? ____________________________________________________________________________________________________________________________________

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50) What changes in the interaction with the temperature increase? ____________________________________________________________________________________________________________________________________

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The reaction produces a thermal energy up to 600 ° C which reduces the amount of product.

In order for scientists to overcome this problem, the manufacturers re-pass the components

on a catalyst, cooling reaction and repeat the process four times, raising the percent yield up

to 98%.

Documents

Nickel Ni Uchemya.weebly.com/uploads/2/8/9/7/28974683/stoichiometry.pdf · 2019-04-20 · used and amounts of products formed by a chemical reaction. Stoichiometry is based on the