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WELCOME TO THE 2010CHEMISTRY TEACHERS’ DAY

Jointly hosted by the School of Chemical and Physical

Sciences, Victoria University of Wellington

and the Wellington Branch of the New Zealand Institute of

Chemistry

PROGRAMME8.55 Welcome Professor John Spencer – SCPS

Dr Joanne Harvey– NZIC Wellington9.05 Associate Professor Kate McGrath – SCPS 9.35 Dr Ben Ruck – SCPS 10.05 Awhina presentation10.40 MORNING TEA11.00 Students: Emma Dangerfield and John Watt11.30 Sheila Woodgate – Lessons from Bestchoice12.00 Teaching and Learning – sharing ideas

- Senior Subject Guidelines, Nature of Science and NZ stories - Writing logical and concise answers – Toulmin analysis- Concept inventory, misconceptions and clickers- SCPS Outreach and IYC2011- FORUM; Teachers sharing and questions

1.00 LUNCH1.30 Workshop 12.30 Workshop 2

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WORKSHOPS1.30 – 2.30 Engaging Maori and Pasifika students (LB203)

Titrations with slime + titrating for Ka (LB116)Bestchoice (LB201)Teaching scholarship classes (AM104)Lab tourExam Analysis (AM102)

2.30 – 3.30 Natural dyes (LB203)Titrations with slime + titrating for Ka (LB116)Bestchoice (LB201)Spectroscopy (LB408)Teaching Level 1 Chemistry/Science (AM104)Lab Tour

RESOURCESScience Teaching and Learning Guide

Part 1 content (MOE approved – 15 November, 2010)

Science: about this guideScienceScience in Te Marautanga o AotearoaThe dynamic process of scienceThe science curriculum: What is changed?What is the Nature of Science strand about?What is biology /chemistry/physics/Earth and space science about?Interpreting the Nature of Science aims in a biology /chemistry/physics/Earth and space science contextWhy study science/biology /chemistry/physics/Earth and space science?Key concepts: science/ biology /chemistry/physics/Earth and space scienceAchievement aimsAchievement objectives by level and strandAchievement objectives: Nature of Science/ biology /chemistry/physics/Earth and space science with INDICATORS AND CONTEXT ELABORATIONS

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Achievement objectives: Chemistry

Considerations for teachers

• Central to all study of chemistry is the recognition that, for any substance, the properties and behaviours that we can observe and measure are the result of the properties and behaviours of sub-microscopic particles that we cannot see; it is of these particles that the substance is made.

• Chemists carry out reactions at what is known as the macroscopic level, and they think about reactions at the particulate or sub-microscopic level. They often use symbols to represent their observations.

• All learning in chemistry should be related to its practical applications in everyday life.

• To make the necessary connections, a chemistry programme should include learning in all three achievement objectives at each level of the curriculum.

Progression in chemistry• Students’ progress in learning chemistry is demonstrated by their

increasingly sophisticated ability to identify, explain, apply and reflect on the role of chemistry in the natural and physical world. This will be observed when they relate the properties of a range of groups of substances to the nature of the particles of which they are made and to the symbols and conventions of chemistry.

• As they progress, students move:• from a focus on matter and the changes it undergoes to a focus on

the composition and properties of matter and the energy involved as it undergoes change;

• from a focus on how substances behave in isolation to a focus on how they interrelate; this may include consideration of their impact on society;

• from a focus on observing the behaviour of substances to a focus on explaining these observations using the fundamental concepts of chemistry;

• from a focus on understanding the nature of particles to a focus on using their understanding of the nature of particles to predict the properties and reactions of materials.

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Achievement objective MW 6-1Students will: Identify patterns and trends in the properties of a range of groups of substances, for example, acids and bases, metals, metal compounds, and hydrocarbons; Explore factors that affect chemical processes.Indicators• Collects and collates data on the chemical and physical properties

of a variety of substances;• Classifies substances by physical properties such as hardness or

conductivity;• Classifies substances by chemical properties such as reactivity in air

or water;• Predicts the chemical or physical properties of substances based on

membership of a known group;• Justifies the choice of a substance for an application based on its

chemical and physical properties;• Relates the rate of a reaction to changes in surface area and

concentration.

Possible context elaborations

• What conditions cause corrosion and rust and how can we prevent it from happening?

• How do we extract iron from iron sand? Why can we “pan” for gold but not for iron?

• What conditions slow down the decay of food or speed up cooking processes?

• Which hydrocarbon makes the best fuel?

• Why do we use kindling to light a fire but logs once it is well lit?

• Which substance makes a good antacid?

• How can I choose the best metal for a piece of jewellery?

• How does the pH of a substance (for example, shampoo, bathroom cleaner, vinegar) relate to its usefulness?

• What is the best way to get a cake to rise?

• A “cycle of copper reactions” that can be classified according to the interactions of the particles.

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http://www.understandingscience.org/

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LOGICAL PLANNED COHERENT ANSWERS

TOULMIN ANALYSIS – CONSTRUCTING AN ANSWER

Claim - a conclusion derived from the data / focus of the argument

Data – measurements/ observations on which the claim is based / evidence

Warrant – links data to the claim / supports the claim

Backing – additional information or support for the warrant

Qualifier – may indicate the strength of the leap from the data to the claim / limitations of the claim

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Working as a group, make a list of the structural characteristics that are similar in all molecules in Table 1 of Model 1 and all the structural characteristics that differ among the molecules in Table 1 of Model 1.

Circle or highlight and label all Claims, Data, Warrants, Backing, that you can identify in each of the four interpretations (1->4) in Model 1 and place a check in the boxes in Table 2 below to indicate Toulmin elements present in each interpretation (1 -> 4).

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Compound Electrical Conductivity pH

NH3 Slight 11.1

NH4NO3 Good 5.1

HNO3 Good 1.0

Data - pH decreasing

Claim – [H+] increases as acid strength increases

Warrant – stronger acids dissociate more and produce more H+

Backing – NH3 is a base so [OH-] > [H+] sp pH > 7NH3 + H2O NH4

+ + OH-

NH4NO3 is a salt that dissociates to produce NH4+

NH4+ is a weak acid so produces only small [H+]

NH4+ + H2O NH3 + H3O+

HNO3 is a strong acid and completely dissociates so produces maximum [H+]

HNO3 + H2O → H3O+ + NO3-

Compound Electrical Conductivity pH

NH3 Slight 11.1

NH4NO3 Good 5.1

HNO3 Good 1.0

Data – Conductance smaller for NH3 than NH4NO3 and HNO3

Claim – There are more ions present in NH4NO3 and HNO3

Warrant – NH4NO3 and HNO3 are ionic compounds

Backing – Ionic compounds dissociate completely in water releasing

the ions.

NH3 is a molecular compound; the reaction with water does not go to

completion (equilibrium) so only a small number of ions are produced

Data –

Claim –

Warrant –

Backing –

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EXAMPLE 1: Explain why water has a higher boiling point than hydrogen sulfide, H2S

Data – water has a higher boiling point than H2S

Claim – water has stronger intermolecular forces

Warrant – water molecules can hydrogen bond to each other

Backing - hydrogen bonding occurs when an H atom is bonded to an atom of a strongly electronegative element (O, N or F). The electronegative atom pulls the electron density away from the hydrogen atom. The hydrogen atom takes on a strongly ‘partial’ charge δ+ and attracts ‘lone pairs’. O is more electronegative than S

EXAMPLE 2: Discuss reasons for NH3 being a stronger base than PH3.

Data – NH3 is a stronger base than PH3

Claim – NH3 is able to attract protons better than PH3

Warrant – NH3 has a more concentrated region of –ve charge than PH3

Backing – N is more electronegative than P so the bonds with H are more polar giving a greater charge separation in the molecule

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Which of the following is responsible for the heat?

A. Breaking hydrogen bonds gives off energy

B. Breaking oxygen bonds gives off energy

C. Forming hydrogen-oxygen bonds gives off energy

D. Both A and B are responsible

E. A, B and C are responsible

Heat is given off when hydrogen burns in air according to the equation

2H2(g) + 2O2(g) 2H2O(g)

Which if any, of the properties would be the same for one

single atom of sulfur obtained from the sample?

A. i and ii only

B. iii and iv only

C. iv only

D. All of the properties will be the same

E. None of the properties will be the same

Following is a list of properties of a sample

of solid sulfur

i brittle, crystalline solid

ii melting point 113°C

iii density of 2.1 g cm-3

iv combines with oxygen to form sulfur dioxide

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POGILSOLUTIONS and CONCENTRATIONINFORMATION: The concentration of solute in an aqueous solution can be

expressed in many ways e.g. grams of solute per dm3 of solution, grams of solute per 100 grams of water (% w/w). The most frequently used concentration is moles per litre ( mol L–1 or mol dm–3).

Concentration can be found using the relationship: c =

When a substance is dissolved in a liquid a solution is formed. Most chemical reactions occur in solution. A solution is usually a liquid (solvent) in which one or more chemicals species (solutes) are dissolved. Most of the solutions we use are aqueous solutions i.e. water is the solvent.

MODEL 2:

V

n

dmlitresinsolutionofvolume

solutionofmoles3

)(

250 dm 3

10 g Na2SO

4

or 7.04 x 10-2 mol Na2SO

4

or 14.1 x 10-2 mol Na+ ions

or 7.04 x 10-2 mol SO42- ions

QUESTIONS:1. Verify that when 10 g of sodium sulfate dissolves in 250 dm 3 water there are:

(a) 7.04 × 10–2 mol of sodium sulfate in water(b) 7.04 × 10–2 mol of sulfate ions in the water(c) 14.1 × 10–2 mol of sodium ions in the water

2. (a) What is the concentration of sodium sulfate in Model 2?(b) What is the concentration of sulfate ions in Model 2?(c) What is the concentration of sodium ions in Model 2?

3. Decide which is more concentrated with respect to sodium ions, 50.0 g of NaCl in 500 cm3 of solution or 59.0 g of Na2SO4 in 500.0 cm3 of solution. Justify your answer.

4. Determine the aluminium ion and the chloride ion concentration in 0.125 mol dm–3

AlCl3.5. Determine the chromium ion concentration and the sulfate ion concentration in a

300 cm3 solution that contains 5.00 g of chromium (III) sulfate.

PROBLEMS1. Calculate the concentration of a solution made by dissolving 2.72 g of

Na2CO3.10H2O in sufficient water to make 250 cm3.

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The molecular formula for this molecule is:

A. C18H27NO3

B. C19H30NO3

C. C17H25NO3

D. C18H25NO3

The functional groups in the molecule above are:

A. ketone, alcohol and alkyne

B. aldehyde, alcohol and alkyne

C. ketone, alcohol and alkene

D. aldehyde, alcohol and alkene

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The molecular formula for this molecule is:

A. C18H27NO3

B. C19H30NO3

C. C17H25NO3

D. C18H25NO3

Select the correct name for the following compound.

A. 1,1,3-triethyl-2-methylbutane

B. 1,1-diethyl-2,3-dimethylpentane

C. 2,4-diethyl-3-methylhexane

D. 3-ethyl-4,5-dimethylheptane

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Which of the following compounds has the lowestboiling point?

A. B. C. D.

The classification for the following reactions is:

OH

O

OH

O

OH

OOH

I

II

III

O

O

A. I – Elimination II – Addition III – OxidationB. I – Substitution II – Addition III - SubstitutionC. I – Addition II – Substitution III - OxidationD. I – Elimination II – Addition III - Substitution

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The major product for the following reaction is:

Treatment of pentan-1-ol with concentrated sulfuric acid, followed by reaction with HBr gives which of the following compounds as the major product?

A B C D

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Treatment of cyclopentene with dilute sulfuric acid, followed by reaction with chromic acid gives which of the following compounds as the major product?

O

OH

OH O

O

Oa) b) c) d)

Which is the major product of the following reaction?

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OH

Heating an alcoholic solution of sodium hydroxide and 1-bromopentane at 60°C yields primarily:

A. B C D

Which reactions can be used to prepare an ester?

COH

O

CO Na

O

COH

O

CNH2

O

SOCl2

H3O

OH

+OH

+OH

OH+

heat

I

II

III

IV

A. I, IIIB.I, IIC.III, IVD.II, IV

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heat

Pt / H2H3PO4CH3CHCH2OH

CH3

d)c)

b)a)

CH3CH2CH2CH3CH3CHCH3

CH3

CH3CHCOH

CH3

O

CH3CHCH

CH3

O

Which is the major product of the following reaction?

COH

O

CH3CH3

CN

O CH3

CH3

SOCl2 (CH3)2NH

NaOH

NH3 CH3CH2Br

room temp

(CH3)2NH

(CH3)2NH

a)

b)

c)

d)

Which are the best conditions for the following preparation?

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The electron configuration of an element X is 1s2

2s2 2p6 3s2 3p3. What is the formula of the most probable compound that X will form with Ca?

A.CaX2 B. Ca3X2

C. Ca2X D. Ca2X3

Which of the following atoms has the greatest tendency to lose an electron?

A. Cs B. Ca C. Na D. As

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Which of the following compounds is likely to be ionic?

A. SO2 B. BrCl C. CaO D. BH3

Which of the following is true?

A. Noble gas atoms generally occur in molecules

B. A noble gas has a smaller radius than an atoms with either one more or one less proton and electron

C. Noble gas atoms lose and gain electrons easily

D. None of the above

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Which of the following is not a property of ionic solids?

A. Brittleness

B. High meting point

C. Hard

D. Poor electrical conductivity

Which of the following is most likely to be an ionic solid?

A. SiC

B. AlCl3C. SO2

D. SiCl2

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Which of the following has the largest dipole moment?

(a) NH3 (b) PH3

(c) ASH3 (d) SbH3

Which of the following is a polar molecule?

(a) SiO2 (b) SO3

(c) IF5 (d) SiF4S

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Which of the following molecules do not form hydrogen bonds?

(a) CH4 (b) NH3

(c) OH2 (d) HF

2011 International Year of Chemistry

ThemesInternational theme: “Chemistry – our life, our future” There is an IYC2011 logo developed by IUPAC (http://www.chemistry2011.org/participate/marketing-materials/)New Zealand theme: Energy, Air, Water, HealthWomen in science, celebrating the 100th anniversary of Marie Curie’s Nobel PrizeIt is also 100 years since the discovery of superconductivity

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THE CHEMISTRY VARIETY SHOWPresentation to Year 12 and 13 secondary school science students

Friday 11 February, 9-10.45am Ilott Theatre, Town Hall,

9.00am Professor Richard Blaikie’s light fantastic show

9.15am Dr Kerstin Burridge-Lucas presents the merino gold fashion collection

9.30am TV7 presenter Dr John Watt revs up

9.45am Nobel Prize winner, Sir Anthony Leggett

10.00 – 10.45am A drink, something to eat, and the chance to talk to some young

scientists about university study and careers in science.

Outreach Educational Programme inChemistry, Physics and Electronic Engineering

For further information or bookings, please contact Helen Rowley

helen.rowley@vuw.ac.nz; phone: 04 463 5335; fax: 04 463 5241

JUNIOR PROGRAMME

Times: 9.30 am to 12.00 noon

Dates: 1 November– 19 November Maximum 40 students per school

SENIOR WORKSHOPS

Workshops are 120 minutesStarting Times: 9:30am & 12:30pm

• Chemistry Dates: 14 June – 25 June

Maximum 24 students per session

• PhysicsDates: 14 June – 30 June

Maximum 24 students per session

• ElectronicsDates: 14 – 30 June

Maximum 18 students per session

OTHER EVENTS

• Titration Competition and Quiz: 16 June

• Chemistry Scholarship Practical

Workshop: 30 June

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2-(2,5-bis(3,3-dimethylbut-1-ynyl)-4-(2-(3,5-di(pent-1-ynyl)phenyl)ethynyl)phenyl)-1,3-dioxolane.

NanoKid

For those of you who think I’m joking……..Journal of Organic Chemistry, 2003, 68, 8750.