Chem 1510 Chap 4 Smartbook

Which of the following options identify the correct coefficients required to balance the reaction illustrated?

- CO2 is a product and has the coefficient 2 - The reactant CO must have the coefficient 2

True or false: To calculate the overall percent yield for a multistep process, add the individual percent yields together.

False

Percent yield

actual yield/theoretical yield × 100

Given the balanced equation 2Al(s) + 3Cl2(g) → 2AlCl3(s), select all the conversion factors that correctly represent the molar relationships in this equation.

-2 mol AlCl3/3 mol Cl2 -2 mol Al/3 mol Cl2

Given the balanced equation Ag2S(s) + 2HCl(aq) → 2AgCl(s) + H2S(g), determine the moles of HCl required and the mass of AgCl formed from the complete reaction of 18.3 g of Ag2S.

-21.2g of AgCl are formed -0.148 mol HCL are required

Hydrogen and nitrogen react to form ammonia according to the balanced equation 3H2 (g) + N2 (g) → 2NH3 (g). In a particular reaction vessel, 4.5 mol of H2 are reacted with 4.5 mol of N2. Which of the following options correctly describe how to complete the reaction table given? Select all that apply.

-the final quantity of NH3 present is 3.0 mole -the change in moles of N2 (a) is equal to -1.5

When hydrogen gas is passed over powdered iron(III) oxide, iron metal and water vapor are formed. Which of the following is the correct balanced equation for this process?

3H2(g)+Fe2O3(s)-->2Fe(s)+3H2O(g)

Which of the following statements correctly describe the percent yield in a chemical reaction? Select all that apply.

-The actual yield is almost always less than the theoretical yield. -% yield = actual yield/theoretical yield × 100

Compound B2 (represented by the red spheres) reacts with AB, as shown in the illustration. From the illustration, the reagent in excess is _____, and the limiting reagent is _____.

B2, AB

A chemical equation must be balanced. This means that the same _____ and _____ of atoms must appear on both sides of the equation.

number, type

Iodine trichloride is produced in a two-step process, represented by the following balanced equations: I2 (s) + Cl2 (g) → 2ICl (s)I2 (s) + Cl2 (g) → 2ICl (s); and ICl (s) + Cl2 (g) → ICl3 (s)ICl (s) + Cl2 (g) → ICl3 (s). Select all the statements that correctly describe how to write a complete balanced equation for the overall process.

-the overall equation is given by I2 (s) + 3Cl2(g)-->2ICl3(s) -the second equation must be multiplied by 2

Actual Yield

Amount of product obtained experimentally from a chemical reaction

Which of the following statements describe the information that can be gained from a balanced chemical equation?

- The relative quantity(moles) of substances involved - The identities of substances involved - The physical States of reactant and products, often

Theoritical yield

The amount of product calculated from the molar ratio in the balanced chemical equation

Which of the following statements correctly describe the information conveyed by the balanced equation 16Cu (s) + S8 (g) → 8Cu2S (s)? Select all that apply.

-16 moles of Cu react with 1 mole of S8 to form 8 moles of Cu2S - Cu and S8 are reactants and Cu2S is the product -16 atoms of Cu react with 1 molecule of S8 to form 8 formula units of Cu2S

Correctly order the steps necessary to balance a chemical equation.

1) Place reactant on the left of the reaction arrow, and products on the right 2) Balance the Atoms 3) Adjust the coefficients such that there are the smallest whole- number at coefficients 4) Do a final check to make sure the equation as balanced

B2 reacts with AB to form AB2 according to the balanced equation B2 + 2AB → 2AB2. If 1.5 moles of B2 are reacted with 1.5 moles of AB, the maximum amount of AB2 that can form is equal to _____ moles.

1.5

Given the balanced equation 3H2(g) + N2(g) → 2NH3(g), calculate the mass of NH3 produced by the complete reaction of 2.55 g of H2.

14.4 g

A particular reaction is expected to yield 125 g of calcium. The actual amount of calcium obtained is equal to 105 g. Calculate the percentage yield for the reaction.

84.0%

Correctly order the steps necessary to calculate the mass of product formed in a chemical reaction, given the masses of all reactants.

- Determine the moles of each reactant present by dividing its mass by its molar mass - Determine the amount of product that could be formed from each reactant using the appropriate mole ratios - I identify the limiting reactant as the reactant that produces the least amount of product - To find the mass, multiply the number of moles product formed (from the limiting reactant) by the molar mass of the product.

Correctly order the steps necessary to solve for the mass of a product, or second reactant required, given the mass of one of the reactants in a chemical process.

- Write a balanced equation for the reaction - Convert the given mass into moles using molar mass. Convert moles of A to moles of B using a conversion factor derived from the balanced equation - Convert the most of the 2nd substance to mass using its molar math

Which of the following options correctly describe the symbols used to write a balanced equation?

-A liquid is indicated by the symbol (l). -The symbol (g) indicates a substance in the gas phase.

Which of the following statements correctly interpret the balanced chemical equation 4HCl (aq) + MnO2 (s) → MnCl2 (aq) + 2H2O (g) + Cl2 (g)?

-HCl is a reactant in this equation -The MnCl2 produced is dissolved in water

Which of the following actions are permitted in balancing a chemical equation?

-Multiplying all coefficients by a common factor - Inserting coefficients and front of formulas of reactants and products

Hydrogen and oxygen react to form water according to the balanced equation 2H2 (g) + O2 (g) → 2H2O (l). In a particular reaction vessel, 2.2 mol of H2 are reacted with 2.2 mol of O2. Which of the following options correctly describe how to complete the reaction table given?

-The change in moles of H2 (a) is equal to -2.2. -Identify H2 as the limiting reactant. -The change in moles of O2 (b) is equal to -1.1.

Under certain conditions, the reaction of propane and water will produce carbon dioxide and hydrogen gas. The reaction may be represented as a two-step process: C3H8 (g) + 3H2O (g) → 3CO (g) + 7H2 (g) CO (g) + H2O (g) → CO2 (g) + H2 (g) Select the statements that correctly describe how to write a complete balanced equation for the overall process.

-The second equation must be multiplied by 3. -The overall equation is given by C3H8 (g) + 6H2O (g) → 3CO2 (g) + 10H2 (g)

Which of the following steps would be required to convert between the masses of any two substances involved in the same chemical reaction?

-Write a balanced chemical equation for the reaction. -Write a conversion factor using the coefficients from the balanced equation, and convert to moles of the second substance. -Convert from the given mass to moles of the same substance.

A useful method for keeping track of quantities in a chemical reaction is a reaction table. Which of the following are components of a reaction table? Select all that apply.

-final amount of reactants and products remaining after the reaction -initial amounts of reactants and products before reaction -change in the amounts of reactants and products during the reaction -a balanced chemical equation

In order to calculate the overall % yield for a multistep process ___________.

-multiply the individual % yields by each other

In a limiting-reactant problem, the final quantities in a reaction table will show ______.

-the amount of the reactant in excess -one of the reactants totally consumed (final amount is zero)

Which of the following statements correctly describe the steps used to determine which reactant in a given reaction is limiting? Select all that apply.

-the reactant that produces the least amount of possible product is the limiting reactant -calculate the molar masses of any reactants for which a mass has been given -calculate the amount of product that could be formed from each reactant

The balanced equation 2S(s) + 3O2(g) → 2SO3 (g) is given. The number of moles of SO3 that will form from the complete reaction of 1.5 mol of O2 is given by _____.

1.5 mol O2 x 2mol SO3/3mol O2

Identify the whole number coefficients required to balance the chemical equation SO2(g) + O2(g) → SO3(g) correctly. (Enter ALL numbers, including the digit 1 if required, and make sure you have the simplest ratio of coefficients.)

2, 1, 2

A reaction is expected to produce 83.5 g of CaCO3. The percent yield is recorded as 62.5%. What is the actual mass of CaCO3 obtained?

52.2

True or false: In order to balance the reaction of hydrogen gas (H2) with oxygen gas (O2) to form liquid water (H2O), a student adds a subscript of 2 after the oxygen in H2O. This is an acceptable method of balancing the above reaction.

False

A chemical equation is a statement using chemical _______ that expresses both the identities and the relative ____________ of the reactants and products involved in a chemical or physical change.

formulas, quantity