Kinetics

Which phase change results in an increase in entropy?

• I₂(g) → I₂(s)

• CH₄(g) → CH₄(l)

• Br₂(l) → Br₂(g)

• H₂0(l) → H₂O(s)

Based on Table I, which equation represents a reaction with the greatest difference between the potential energy of the products and the potential energy of the reactants?

• 4Al(s) + 3O₂(g) →2Al₂O₃(s)

• 2H₂(g) + O₂(g) → 2H₂O(l)

• C₃H₈(g) + 5O₂(g) → 3CO₂(g) + 4H₂O(l)

• C₆H₁₂O₆(s) + 6O₂(g) → 6CO₂(g) + 6H₂O(l)

Hydrochloric acid reacts faster with powdered zinc than with an equal mass of zinc strips because the greater the surface area of the powdered zinc

• decreases the frequency of particle collisions

• decreases the activation energy of the reaction

• increases the frequency of particle collisions

• increases the activation energy of the reaction

In terms of disorder and energy, systems in nature have a tendency to undergo changes toward

• less disorder and lower energy

• less disorder and higher energy

• greater disorder and lower energy

• greater disorder and higher energy

For a chemical system at equilibrium, the concentration of both the reactants and the products must

• decrease

• increase

• be constant

• be equal

Tags

NGSS.HS-PS1-6

Which sample of HCl(aq) reacts at the fastest rate with a 1.0-gram sample of iron filings?

• 10. mL of 1 M HCl(aq) at 10.^oC

• 10. mL of 1 M HCl(aq) at 25^oC

• 10. mL of 3 M HCl(aq) at 10.^oC

• 10. mL of 3 M HCl(aq) at 25^oC

Tags

NGSS.HS-PS1-5

Chemical systems in nature tend to undergo changes toward

• lower energy and lower entropy

• lower energy and higher entropy

• higher energy and lower entropy

• higher energy and higher entropy

Tags

NGSS.HS-PS3-4

The effect of a catalyst on a chemical reaction is to provide a new reaction pathway that results in a different

• potential energy of the products

• heat of reaction

• potential energy of the reactants

• activation energy

Equilibrium can be reached by

• physical changes, only

• nuclear changes, only

• both physical changes and chemical changes

• both nuclear changes and chemical changes

Based on Table I, which compound dissolves in water by an exothermic process?

• NaCl

• NaOH

• NH₄Cl

• NH₄NO₃