Summary

AVOGADRO EXAM 2011
UNIVERSITY OF WATERLOO
DEPARTMENT OF CHEMISTRY


19 MAY 2011 TIME: 75 MINUTES

This exam is being written by several thousand students. Please be sure that you follow the instructions below.
We'll send your teacher a report on your performance. Top performers are eligible for a prize. The names of the top 200
students will be published in the September issue of Chem 13 News.




1. Print your name here:


2. Print your school name and city on your STUDENT 4. Print your name (last name, first name and optional
RESPONSE sheet. middle initial) on the STUDENT RESPONSE sheet.
Also fill in the corresponding circles below your printed
3. Select, and enter on the STUDENT RESPONSE name.
sheet, one of the following CODE numbers:
5. Carefully detach the last page. It is the datasheet.
Code 1 Ontario, now studying Grade 11 Chemistry
in a nonsemestered school
Code 2 Ontario, now studying Grade 11 Chemistry 6. Now answer the exam questions. Questions are not in
order of difficulty. Indicate your choice on the
in a semestered school
STUDENT RESPONSE sheet by marking one letter
Code 3 Ontario, Grade 11 Chemistry beside the question number.
already completed
• Mark only one answer for each question.
Code 4 Any other Ontario student
• Questions are all of the same value.
Code 5 Manitoba or Saskatchewan high school
student • There is a penalty (1/4 off) for each incorrect
answer, but no penalty if you do not answer.
Code 6 Québec high school student
Code 7 not used 7. Take care that you make firm, black pencil marks, just
Code 8 Alberta or British Columbia high school filling the oval.
student
Be careful that any erasures are complete—make the
Code 9 New Brunswick, Newfoundland, Nova Scotia,
sheet white again.
or Prince Edward Island high school student
Code 10 Northwest Territories, Nunavut, or Yukon
high school student
Code 11 High school student outside Canada
Code 12 Teacher




Carefully detach the last page.
It is the Data Sheet.

, 1 Iodine-131 is a radioactive isotope used to treat 5 A student prepared the following graph to illustrate
hyperthyroidism (an overactive thyroid gland) and one aspect of ideal gas behaviour. However, he forgot
thyroid cancer. How many protons, neutrons and to label the axes.
electrons are there in a single atom of iodine-131?

A 131 protons, 131 neutrons, 131 electrons

B 53 protons, 78 neutrons, 53 electrons

C 78 protons, 53 neutrons, 78 electrons

D 53 protons, 131 neutrons, 53 electrons Which of the following graphs could it be?
Note: In the responses below, the symbols have their
E 78 protons, 131 neutrons, 78 electrons
usual meanings: P is pressure; V is volume; T is kelvin
temperature; n is amount in moles.
2 Data are given below for the hypothetical element
A P versus T, with n and V held constant
avogadrium, symbol Av. What is the average atomic
weight of avogadrium?
B T versus n, with P and V held constant
Relative Fractional
C PV versus T, with n held constant
Isotope weight abundance
Av-58 58.017 u 36.02% D P versus V, with n and T held constant
Av-60 60.154 u 63.98%
E PV/T versus P, with n held constant
A 58.79 u
B 59.09 u
6 Which substance, in the solid state, is likely to have
C 58.55 u the following characteristics: hard; brittle; soluble in
water; high melting point?
D 59.38 u

E 59.62 u A Cl2

B RbCl

3 Which of the following equations is not correct? C C(diamond)
A H2(g) → 2 H(g) + energy D Cu
− −
B Na(g) + e → Na (g) + energy
− E IBr
Mg(g) + energy → Mg (g) + 2e
2+
C
D Cu(s) + energy → Cu(l)
− 7 The mass of a sample is measured as 0.03050 g. How
Na (g) + Cl (g) → NaCl(s) + energy
+
E many significant figures are there in this quantity?

A two
4 How many electron pairs are there around the S atom
−
in the SF3 ion? B three
A three bonding pairs
C four
B three bonding pairs and one unshared pair
D five
C three bonding pairs and two unshared pairs
E six
D four bonding pairs and two unshared pairs

E six bonding pairs

2 / AVOGADRO EXAM © 2011 UNIVERSITY OF WATERLOO