CHEM 109 ACS Second half

A + B -> C + D
is first order in [A] and second order in [B]. If [A] is halved and [B] is doubled, the rate of the reaction will

• remain the same.
• be increased by a factor of 2
• be increased by a factor of 4
• be increased by a factor of 8

Tags

NGSS.HS-PS1-5

The activation energy for a particular reaction is 83.1 kJ * mol^-1. By what factor will the rate constant increase when the temperature is increased from 50.0 C to 60.0 C?

• 10.0
• 2.53
• 0.927
• 0.395

Tags

NGSS.HS-PS1-5

The half-life for the radioactive decay of ³²P is 14.2 days. How many days would be required for a sample of a radiopharmaceutical containing ³²P to decrease to 20% of its initial activity?

• 33.0 d
• 49.2 d
• 71.0 d
• 286 d

Tags

NGSS.HS-PS1-8

^{The forward reaction (1) is proceeding at a certain rate at some temperature and pressure. When the pressure is increased, what might we expect for the forward reaction?}

• a greater rate of reaction and a greater yield of SO₃ at equillibrium
• a greater rate of reaction and the same yield of SO₃ at equillibrium
• a lesser rate of reaction and a smaller yield of SO₃ at equilibrium
• a lesser rate of reaction and a greater yield of SO₃ at equilibriu

In a chemical reaction involving the formation of an intermediate activated complex, which step must always be exothermic?

• reactants -> products
• products -> reactants
• reactants -> activated complex
• activated complex -> products

Tags

NGSS.HS-PS1-4

The gas-phase reaction, A₂ + B₂ -> 2AB, proceeds by bimolecular collisions between A₂ and B₂ molecules. If the concentrations of both A₂ and B₂ are doubled, the reaction rate will change by a factor of

• 1/2
• sqrt(2)
• 2
• 4

Tags

NGSS.HS-PS1-5

2NO(g) + Cl₂(g) -> 2NOCl(g)
doubling the concentration of chlorine doubles the rate of reaction. Doubling the concentration of both reactants increases the rate of reaction by a factor of eight. The reaction is

• first order in both NO and Cl₂
• first order in NO and second order in Cl₂
• second order in NO and first order in Cl₂
• second order in both NO and Cl₂

Tags

NGSS.HS-PS1-5

Under certain conditions, the average rate of appearance of oxygen gas in the reaction
2O₃(g) -> 3O₂(g)
is 1.2 x 10^-3 atm * s^-1. What is the average rate, expressed in atm *s^-1, for the disappearnace of O₃?

• 8.0 x 10^-4
• 1.2 x 10^-3
• 1.8 x 10^-3
• 5.3 x 10^-3

Tags

NGSS.HS-PS1-5

NGSS.HS-PS1-7

H₂O₂ + 2H⁺ + 2I^- -> I₂ + 2H₂O
is rate = k [H₂O₂] [I^-]. The overall order of the reaction is

• five
• three
• two
• one

Tags

NGSS.HS-PS1-5

The activity of a radioisotope is 3000 counts per minute at one time and 2736 counts per minute 48 hours later. What is the half-life of the radioisotope?

• 831 hr
• 521 hr
• 361 hr
• 1.44 hr