Exam 2017, questions PDF

Preview

Summary

Download Exam 2017, questions PDF

Description

Examination Cover Page

Examination Period: Academic Institution: Academic Group: Academic Career: Examination Type:

AFFIX STUDENT ID STICKER HERE

2017 Term 1 Central Queensland University Higher Education Division Undergraduate Standard

I have read and understood the penalties involved if I do not abide by the rules outlined on the back of this examination paper. Student Signature: Student ID Number Unit: Subject Area: Catalog Number: Paper Number: Component:

Fundamentals of Chemistry CHEM 11042 1 ALL Components

Duration: Perusal Time: First Contact: Second Contact:

120 minutes 15 minutes Leanne Voss - vossl Aoife Power

Restrictions:

Closed Book

Contact Number: Contact Number:

07 49232876 07 49306439

Office Use: Release examination paper via the CQ University Past Exams website two weeks after the DE/SE examination period? Yes

Instructor Authorised/Allowed Materials Dictionary - non-electronic, concise, direct translation only (dictionary must not contain any notes or comments). Calculator - all non-communicable calculators, including scientific, programmable and graphics calculators are authorised. Student Calculator - Make:____________________ / Model: ____________________

Special Instructions to Students: Please see instruction sheet on first page of the examination paper.

Examination Office Supplied Materials 4 x Rough Paper 1 x Exam Answer Booklet 1 x Periodic Table of Elements

QUESTIONS ANSWERED

MARKS

QUESTIONS ANSWERED

MARKS

Number of examination answer booklets used: Number of separate sheets attached (Do not include rough paper):

This examination paper is not to be released to the student at the conclusion of the examination. Central Queensland University considers improper conduct in examinations to be a serious offence. Penalties for cheating are exclusion from the University and cancellation with academic penalty from the unit concerned.

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Instructions: 1.

This examination is comprised of two sections, Sections A and B.

2.

Total marks: 100

Section A 1.

2. 3. 4. 5. 6. 7.

Answer fifty (50) of the sixty (60) questions in Section A by writing one or two words in the space provided on the exam paper. Should the answer be numeric, provision to show your working will be provided as the next question. Each question is worth 1 mark. If you complete more than fifty (50) questions all will be marked and your best attempts will contribute to your mark for this section. There is a maximum score of 50 marks for this section. Make sure you enter your name and student number on each page of Section A of the exam paper. You should spend approximately 60 minutes on this section. Marks for Section A: 50

Section B 1. 2. 3. 4.

Answer Section B in the exam answer booklet supplied. Answer all three (3) questions. You should spend approximately 50 minutes on this section of the examination. Marks for Section B: 50

Page 1 of 20

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

50 MARKS

Section A Name:

Student number:

Question

Topic 1: Matter

1

The state of matter that has definite shape and volume and has strong intermolecular forces is ________.

2

Condensation occurs when a _____________ is transformed to a liquid.

3

Density is a measure of _________ divided by _____________.

4

Compounds are substances that can be separated into different elements by ___________ methods only.

5

The term used to describe a mixture when it has chemical species found in one phase only, is ________________.

Page 2 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name:

Student number:

Question 6

Topic 2: Measurement The correctly reported answer to the following addition of volumes is __________mL. 52.063 mL + 102.0 mL =

7

How many significant figures are present in the following number: 101.010 ? __________ .

8

The correctly reported answer to the following multiplication of distances is _________ mm2. 3.523 mm x 0.025 mm =

9

When repeated measurements provide consistent but incorrect results, they are said to be ____________ but not accurate.

10

When recording measurements both the measured value and its _________ must be recorded.

Page 3 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name:

Question 11

Student number:

Topic 3: Atomic structure and Periodic Table All atoms with the same number of protons have the same atomic ____________.

12

Elements having the same number of valence electrons would be found in the same __________ of the Periodic Table.

13

How many neutrons are present in an atom of the element 226 88 Ra?

14

A theoretical element ‘X’ has 2 isotopes that occur as 80% 40X and 20% 48X, What is the average atomic mass for this theoretical element X?

15

Which subatomic particle is not found in the nucleus of the atom? _____________ .

Page 4 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name:

Question 16

Student number:

Topic 4: Scientific Notation and the Metric System Express 0.005890 in scientific notation to 3 significant figures.

17

Express 5.20 x 10-4 in decimal notation.

18

How many microliters are present in 0.005300 mL?

19

Express 180000 in scientific notation using 3 significant figures.

20

Convert 2255 nanograms to micrograms.

Page 5 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name:

Question 21

Student number:

Topic 5: Molecular formula and the mole Write the molecular formula for potassium dichromate given that it is made up of 2 potassium, 1 chromium and 4 oxygen atoms.

22

Calculate the molar mass of calcium phosphate, Ca3(PO4)2. (show working below)

23

Show working for Q22

24

Calculate the mass in gram of 0.625 mol Fe(NO3)3. (given molar mass = 241.8 g/mol) (show working below)

25

Show working for Q24

Page 6 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name:

Question 26

Student number:

Topic 6: Gas laws and intermolecular forces What is the dominant intermolecular force that is present between molecules of ammonia, NH3 and methanol, CH3OH?

27

Boyles Law explains why that when we breathe in, the pressure of air in the lungs is ________________ than the pressure of air in the atmosphere.

28

Following a fire, an air sample was collected in a flask. The flask was found to contain 0.2 mol of CO (g), 0.04 mol O2 and 0.16 mol of N2. If the concentration of gases in the flask is representative of the air sample at the scene, what is the partial pressure of carbon monoxide at the scene? (assume normal atmospheric pressure of 1 atm)

29

At constant pressure and 250C a gas sample occupies 5 litres. At what temperature will the gas occupy 10 litres? (show working below)

30

Show working for Q29

Page 7 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name:

Question 31

Student number:

Topic 7: Chemical reactions and equilibrium Consider the chemical equation for absorption of potassium in the body: 2K +2H20 -->

H2+2K(OH)

If 0.50 mole of potassium was present, how many mole of hydrogen would be produced? 32

What is the prefix required to balance the following reaction? 2Fe2O3 + 3C ->______ Fe + 3 CO2

33

Consider the reaction for aerobic respiration that occurs in the body. C6H12O6 + 6 O2 --> 6 CO2 + 6 H2O + energy Is this reaction endothermic or exothermic?

34

Write the expression for Kc for the following reaction: 2HCl (g) + I2 (s)  2HI(g) + Cl2(g)

35

Consider the reaction of carbon monoxide and water vapour: CO(g) + H2O (g)  CO2 (g) + H2(g) How would an increase of pressure effect the equilibrium concentration of CO gas?

Page 8 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name:

Student number:

Question 36

Topic 8: Acids, Bases and Buffers A buffer is a solution that resists change in ___________ on addition of small amounts of acid or base.

37

A strong base is a substance that reacts completely with water to produce _______________ ions.

38

Calculate the pH of a solution that is 6.6 x 10 -4 M in H3O+ ions.

39

What is the pH of a buffer solution that 0.15M CH3COOH and 0.25 M CH3COO-. The pKa for acetic acid, CH3COOH is 4.76. (show working below)

40

Show working for Q39.

Page 9 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name:

Question 41

Student number:

Topic 9: Nuclear Chemistry A piece of paper is sufficient to shield form ____________ particles.

42

The intensity of radiation received from a source is inversely proportional to the __________ of the distance from that source.

43

The vital factors in minimising risk to radiation workers are _______, distance, _________ and monitoring.

44

The half-life of a radiation source used internally for a scanning procedure is 3 hours. If the initial intensity is assumed to be 100%, what is the intensity of the radiation after 24 hours? (show working below)

45

Show working for Q44.

Page 10 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name:

Question 46

Student number:

Topic 10: Hydrocarbons and aromatic compounds What is the functional group present in a molecule of C3H6?

47

Draw 2-methylhex-2-ene.

48

Use Markovnikov’s rule to draw the major product of the following reaction: CH3CH=CH2 + HBr _____________

49

What is the IUPAC name for the following molecule?

50

When the carbon atoms of the main chain of an alkene are on the same side of the double bond, the alkene is said to have __________ configuration.

Page 11 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name:

Question 51

Student number:

Topic 11: Aldehydes Ketones, Ethers Alcohols Methanone can be used to help patients off heroin. Based on the name what functional group is present in this drug?

52

Primary alcohols are completely oxidised to _____________________

53

Classify the following alcohol as being primary, secondary or tertiary.

54

The boiling point of alcohols is generally ____________than that of alkanes of similar molar mass.

55

Provide the IUPAC name for the following molecule:

Page 12 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Name: Question 56

Student number: Topic 12: Amines; Carboxylic acids and Chiral Compounds. Methamphetamine, a drug that stimulates the central nervous system, is readily absorbed as it is very _________ in water due to bond _________ between N and H atoms. H H

CH

CH N + CH3 ClH

57

Identify two functional groups present in Lidocaine, a local anaesthetic is shown below.

58

___________ are organic compounds that contain a nitrogen atom and are derived from _________ acids.

59

R2NH is the general formula for a ___________ amine.

60

For a carbon atom to be a chiral centre it must have __________ different substituents.

END OF SECTION A

Page 13 of 20

Answer

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Section B Instructions: • Answer Section B in the exam answer booklet supplied. • Answer all three (3) questions. • Include diagrams as appropriate. • You should spend approximately 60 minutes on this section of the examination. • Marks for Section B: 50

Question 1.

15 MARKS

Apply Lewis dot and VSEPR theory to predict the shape and draw the bonding that occurs in the acetate ion CH3COO- . In your answer you should consider possible resonance structures.

To assist you, a template for Lewis Dot and VSEPR calculations has been attached to this exam paper. DO NOT write on these templates – your answer must be written in the examination booklet.

A total of 15 marks will be awarded for this question, as per the following criteria: •

Calculation of valence electrons in molecule

(2 marks)

•

Lewis dot drawing

(2 marks)

•

Adjusted Lewis dot drawing after minimising formal charge

(3 marks)

•

Identifying basic molecular shape

(2 marks)

•

VSEPR code

(2 marks)

•

Final molecular shape

(2 marks)

•

Comments on effect of lone pairs on bond angles.

(2 marks)

Page 14 of 20

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Question 2.

5+10=15 MARKS

a) A doctor has ordered 2.5 mg of morphine be administered IV to a patient. Given that you have 1 mL ampoules that contain 100 µg of morphine, what volume of morphine would you administer to the patient?

5 marks

b) What volume of a 2.0 M NaCl solution would you need to prepare 250.0 mL of a 0.15 M NaCl solution?

10 marks

Question 3.

2+10+5+3=20 MARKS

Glucose is converted to carbon dioxide and water during respiration. The process provides energy to the body. Consider the chemical equation for this process and answer the following questions: 6 C6H12O6 + 6 O2 -> 6 CO2 + 6 H2O

a) Is this chemical reaction endothermic or exothermic? Explain your answer 2 marks

b) If vigorous exercise is undertaken, oxygen supply to the muscles is reduced and lactic acid build up may occur. Would 50.0 g of glucose be completely metabolised if only 6.00 g of oxygen is available?

In your answer you must consider which reagent is limiting.

10 marks

c) What is the theoretical yield (i.e. mass) of carbon dioxide that would be produced if 50.0 g glucose and 6.00 g of oxygen reacted?

5 marks

d) If only 5.50 g of carbon dioxide were produced, what is the percentage yield for the process that occurred?

3 marks

--- End of paper ---

Page 15 of 20

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Template for Lewis Dot Diagrams Lewis Dot Structure for: Atoms present in molecule

Number atoms present

Electronic configuration

Valence electrons

Total number valence electrons for each type of atom

Adjustment for negative / positive charge Total number of valence electrons in molecule Number of pairs of electrons in molecule Initial Lewis Dot Diagram – showing bond linkages

Number of electron pairs remaining Lewis Dot Diagram with all electron pairs distributed

Formal charge = number of valence e of atom – lone pairs drawn – ½ shared electrons Atoms present in molecule

Valence electrons

e in Lone pairs

½(Total no. shared electrons)

Adjusted Lewis dot diagram (with minimised formal charges)

Page 16 of 20

Formal charge

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

Template for VSEPR stereochemistry Molecule Number of bonding electron charge clouds around atom of interest Number of non-bonding electron charge clouds around atom of interest Total number of electron charge clouds around atom of interest Name of basic molecular shape (From Rule 1) VSEPR Code Comment on the position of any lone pairs present and how they affect bond angles. Draw a three dimensional representation of the final shape of the molecule showing all bonds, consider the effects of lone pairs on bond angles

Name of final molecular shape (From Rule 2)

Total number of electron charge clouds 1 2

Basic molecular geometry

Number of connections

VSEPR code

Number of lone pairs

Final geometry

Linear Linear

3

Trigonal planar

4

Tetrahedral

5

Trigonal bipyramidal

1 2 1 3 2 1 4 3 2 1 5

X2 AX2 AXE X3 AX2E AXE2 AX4 AX3E1 AX2E2 AXE3 AX5

0 0 1 0 1 2 0 1 2 3 0

4 3 2 1 6 5 4 3 2 1

AX4E1 AX3E2 AX2E3 AXE5 AX6 AX5E1 AX4E2 AX3 E3 AX2E4 AXE5

1 2 3 4 0 1 2 3 4 5

linear linear linear trigonal planar bent linear tetrahedral trigonal pyramidal bent linear trigonal bipyramidal see saw T-shaped linear linear octahedral square pyramidal square planar T-shaped linear linear

6

Octahedral

Page 17 of 20

Term 1 2017 Standard Examination 2017 CHEM11042 Fundamentals of Chemistry

GENERAL DATA Powers of ten prefixes

10-12 pico (p) 10-9 nano (n) 10-6 micro (u) 10-3 milli (m) 10-2 centi (c) 10-1 deci (d) 103

kilo (k)

106

mega (M)

109

giga (G)

Temperature 0oC = 273 K 0.0821 L atm K-1mol-1

Universal Gas Constant, R

8.314 J K-1 mol -1 6.022 x 1023

Avogadro Number, NA CHEMICAL CALCULATIONS

Density=

mass volume

Amount (mol) =

Molarity =

SOLUTIONS

mass (g) molar mass (g/mol)

amount (mol) volume (Litre)

Dilution factor=

volume of stock taken total volume of final solution

Volume of stock required=dilution factor x total volume of final solution C1V1=C2V2

Page 18 of 20

Term 1 2017 Standard Examination 2017 CHEM1104...