UNE GEN CHEM 2 MIDTERM NEWEST ACTUAL

UNE GEN CHEM 2 MIDTERM NEWEST ACTUAL /

EXAM QUESTIONS AND CORRECT

ANSWERS.VERIFIED/GRADED A+

A heterogenous catalyst is present in a different phase than the reactants

Which of the following is true about reaction mechanisms?-A reaction mechanism includes intermediates that aren't represented as products or reactants in a balanced chemical equation -Elementary reactions produce unstable transition states -The molecularity of a reaction is the number of intermediate steps in a reaction -The rate-limiting step is the fastest step in a reaction -A reaction mechanism includes intermediates that aren't represented as products or reactants in a balanced chemical equation

A transition state is an unstable species created by the collision and combination of two reactant molecules 1 / 3

The rate constant for a reaction is determined to be 1.23*10^5 s^-1 at 600°C. What is the activation energy for this reaction?169 kJ/mol

According to collision theory the reacting species must collide with enough energy to overlap and combine valence-shell electrons to form new bonds

A catalyst is not consumed during an overall reaction

The elementary reaction CH3 + Cl → CH3Cl is an example of bimolecular reaction

At equilibrium the rate of the forward reaction is equal to rate of reverse reaction

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For the reaction: 2PH3 ↔ P2 + 3H2

If 0.0425 mol of pure PH3 is placed in a 1 L flask at constant temperature and the reaction is allowed to reach equilibrium, the equilibrium concentration of PH3 is 0.0173 M. What is the equilibrium constant for the reaction at this temperature?

2.27*10^-3

For the endothermic reaction O2 → 2O, what effect would increasing the temperature have?The equilibrium will shift right, and the equilibrium constant will change.

The equation for relating Kc and Kp for the reaction 2SO2(g) + O2(g)↔2SO3 (g) is Kp=Kc/(RT)

For the reaction 2BrCl(g) ↔ Br2(g) + Cl2(g), the equilibrium constant at 223°C is 32. If a sample of BrCl is heated to 223°C and allowed to reach equilibrium there will be a significant amount of Br2, Cl2, and BrCl present

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