Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

Exam 3 with Answer Key for General Chemistry II | CHEM 1120, Exams of Chemistry

Material Type: Exam; Class: General Chemistry II; Subject: Chemistry; University: Roane State Community College; Term: Spring 2006;

Typology: Exams

Pre 2010

Uploaded on 08/18/2009

koofers-user-7t1
koofers-user-7t1 🇺🇸

10 documents

1 / 7

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
CHEM 1120 test 3 - Spring 2006 Page 1
Circle the correct answer on the answer sheet.
R = 8.314 J mol-1 K-1 ln(2) = 0.693
H
eRT
kA
Δ
=
1. The rate constant for a reaction is 1.2 × 10-2 s-1 at room temperature (25EC). The activation
energy is 35.0 kJ mol-1. What is the reaction rate constant at 100EC?
a. 7.0 × 1054 b. 2.1 × 10-1 s-1 c. 7.0 × 10-4 d. 0.998 e. 1.002
2. The following data was determined in a kinetics experiment.
time /min pressure /atm time /min pressure /atm
0.00 2.500 4.00 0.338
2.00 0.920 6.00 0.125
What is the order of this reaction?
a. 0th b. ½ order c. 1st d. 2nd e. 3rd
3. The following initial rates were determined for one of the reactants in a reaction.
CM /Mrate /M s-1 CM /Mrate /M s-1
10 1.50 20 6.00
15 3.78 25 9.38
What is the order of the reaction in this reactant?
a. -1st b. 0th c. 1st d. 2nd e. 3rd
4. The half life of a nuclear decay is 15.5 yr. After how many years will there be just 15 % left?
a. 42.4 yr b. 13.0 yr c. 31.0 yr d. 95.0 yr e. 67.0 yr
pf3
pf4
pf5

Partial preview of the text

Download Exam 3 with Answer Key for General Chemistry II | CHEM 1120 and more Exams Chemistry in PDF only on Docsity!

Circle the correct answer on the answer sheet.

R = 8.314 J mol -1^ K-1^ ln(2) = 0.

H^ †

k A e RT

−^ Δ

  1. The rate constant for a reaction is 1.2 × 10 -2^ s -1^ at room temperature (25EC). The activation energy is 35.0 kJ mol -1^. What is the reaction rate constant at 100EC? a. 7.0 × 10^54 b. 2.1 × 10-1^ s -1^ c. 7.0 × 10 -4^ d. 0.998 e. 1.
  2. The following data was determined in a kinetics experiment.

time /min pressure /atm time /min pressure /atm 0.00 2.500 4.00 0. 2.00 0.920 6.00 0.

What is the order of this reaction? a. 0 th^ b. ½ order c. 1 st^ d. 2 nd^ e. 3 rd

  1. The following initial rates were determined for one of the reactants in a reaction. CM / M rate / M s -1^ CM / M rate / M s - 10 1.50 20 6. 15 3.78 25 9. What is the order of the reaction in this reactant? a. -1st^ b. 0 th^ c. 1 st^ d. 2 nd^ e. 3 rd
  2. The half life of a nuclear decay is 15.5 yr. After how many years will there be just 15 % left? a. 42.4 yr b. 13.0 yr c. 31.0 yr d. 95.0 yr e. 67.0 yr
  1. The following is the reaction mechanism for the reaction H 2 + I 2! 2HI. I 2 º 2I.^ fast H 2 + I.^! H 2 I.^ slow H 2 I.^ + I 2! 2HI fast The observed kinetics is given as:

a. rate = k P ' H 2 PI 2

b. 2 2 2 2

' H I^1 (i.e. k'^ H )

I

rate k P P P

P

=^ −

c. rate = k P ' H 2 PI^3

d. rate = k P ' H^2 2 PI 2

e. rate = k P ' H 2 PI^122

  1. The slope of the plot of ln( k ) versus 1/T (an Arrhenius plot) is –2.55 × 10 3 K. What is the value for the activation energy? a. 10 kJ mol -1^ b. 21.2 kJ mol -^ c. 25 kJ mol -11^ d. 46 kJ mol -1^ e. 50 kJ mol -
  2. The following data are the amounts of reactants with respect to time for a first order reaction. What is the rate constant? time /min reactant /g time /min reactant /g 0 16.520 30.0 0. 10.0 6.389 40.0 0. 20.0 2.471 50.0 0. a. 0.095 s -1^ b. 0.22 s -1^ c. 20.0 s -1^ d. 2.0 × 10-2^ s -1^ e. 1.0 × 10 -3^ s -
  3. The organic chemist rule of thumb depends upon most organic reaction having an activation energy of about 50 kJ mol -1^. If this worked, about how much faster would a reaction go if one were to increase the temperature by 10EC starting at room temperature (25EC)? a. half as fast b. 50 % faster (1.5 times faster) c. 2 times faster d. 3 times faster e. 4 times faster
  1. What is the product for the following reaction? CH 3 CH 2 OH + C 6 H 5 COOH presence of sulfuric acid^ >? a. an ether b. an amide c. an ester d. a Nylon® e. a Teflon®
  2. What is the product for the following reaction? CH 2 =CH 2 + Br 2!?

a. b. c. d. e.

  1. Which of the following structures is not a correct organic structure? a. b.

c. d. e.

  1. What is the product in the following reaction? H 2 C=CH 2 UV light or catalysts^ >?

a. b.

c. Teflon ® d. e. Nylon ®

  1. What is the monomer for latex (and rubber) a. b.

c. d. e.

  1. What is the name of the following compound?

a. 2,2,4-trimethylpentane b. 2,2,4-trimethyloctane c. cyclopentane d. isononane e. n-octane

  1. What functional group(s) does the compound have?

a. an amino, an alcohol group and a carboxylic acid group b. a carboxylic acid group c.d. an amide group and an alcohol groupa secondary amino group and an aldehyde group e. an amino and a carboxylic acid group

  1. What is the result of the reaction: CH 3 CH 2 OH presence of sulfuric acid^ >? a. an inorganic ester b. a cyclic hydrocarbon c. an ether d. an organic ester e. TNT

KEY

1.b 2.c 3.d 4.a 5.e 6.b 7.a 8.c 9.b 10.a 11.d 12.c 13.c 14.d 15.b 16.a 17.e 18.a 19.e 20.c