U3E1 Review

Balance the following equation and give the coefficients: ___C₂H₄ + ___O₂ → ___CO₂ + ___H₂O

• 1, 3, 2, 2

• 2, 2, 1, 2

• 1, 2, 2, 1

• 1, 3, 1, 2

Tags

NGSS.HS-PS1-7

Find the number of moles of ammonia (NH₃) produced from a reaction of 4 moles of N₂ gas at STP with excess hydrogen gas.

N2 + 3 H2 --> 2 NH3

• 2 mol

• 8 mol

• 4 mol

• 1 mol

Tags

NGSS.HS-PS1-7

How many grams of oxygen gas are formed from the complete decomposition of 3 moles of hydrogen peroxide? (Molar masses: H₂O₂ = 34 g/mol, H₂O = 18 g/mol, O₂ = 32 g/mol)

2 H2O2 --> 2 H2O + O2

• 16 grams

• 32 grams

• 48 grams

• 64 grams

Tags

NGSS.HS-PS1-7

• 64 g SO3; S is the limiting reactant

• 64 g SO3; O2 is the limiting reactant

• 160 g SO3; O2 is the limiting reactant

• 80 g SO3; S is the limiting reactant

Which reactant is in excess when 32.0 g of O₂ and 64.0 g of S are reacted according to the equation: 2S + 3O₂ → 2SO₃?

• Sulfur is the excess reactant.

• Oxygen is the excess reactant.

• Both reactants react completely.

• Excess reactant cannot be determined.

Which of the following is true of a general thermodynamic state function?

• The change in the value of the state function is always positive for endothermic processes.

• The change of the value of a state function is independent of the path of a process.

• The value of the state function remains constant.

• The value of a state function does not change with a change in temperature of a process.

• The change in the value of a state function is always negative for a spontaneous reaction.

Consider two cylinders of gas, both with a volume of 25 L and at 1 atm and 25ºC. Which statements is/are true?

I. The average kinetic energy of the gases is the same

II. The temperature of the gases is different

III. The average molecular speed of the gases is the same

• I

• II and III

• I and II

• I, II and III

Tags

NGSS.HS-PS3-2

Which of the following Kinetic Molecular Theory statements is/are true?

I. There is an inverse relationship between the temperature of a gas and its kinetic energy

II. Gas molecules have elastic collisions in which the ere is no net loss in kinetic energy

III. The smaller the molar mass of a gas, the slower it moves

• I, II, III

• III

• I, II

• II

The graph shows the Maxwell distribution plots for a given gas at three different temperatures. Which plot corresponds to the lowest temperature?

• A

• B

• C

• It cannot be determined from this graph.

At constant temperature, the rate of effusion of He is ________.

• seven times that of N₂

• twice that of CH₄

• twice that of H₂

• half that of CH₄

Tags

NGSS.HS-PS3-2