Level 3 Chemistry (91391) 20189 1 3 9 1 M
© Mana Tohu Mtauranga o Aotearoa, 2018. Pmau te mana. Kia kaua rawa he whi o tnei tuhinga e whakahuatia ki te kore te whakaaetanga tuatahi a te Mana Tohu Mtauranga o Aotearoa.
M TE KAIMKA ANAKE
TAPEKE
Te Mtauranga Mat, Kaupae 3, 2018 91391M Te whakaatu mramatanga ki ng huatanga
o ng phui whaiwaro
2.00 i te ahiahi Rpare 15 Whiringa--rangi 2018 Whiwhinga: Rima
Paetae Kaiaka Kairangi Te whakaatu mramatanga ki ng huatanga o ng phui whaiwaro.
Te whakaatu mramatanga hhonu ki ng huatanga o ng phui whaiwaro.
Te whakaatu mramatanga matawhnui ki ng huatanga o ng phui whaiwaro.
Tirohia mn e rite ana te Tau konga -Motu (NSN) kei runga i t puka whakauru ki te tau kei runga i tnei whrangi.
Me whakamtau koe i ng tmahi KATOA kei roto i tnei pukapuka.
He taka pmotu kua whakaritea ki te Puka Rauemi L3-CHEMMR.
Mn ka hiahia whrangi atu an koe m tuhinga, whakamahia ng whrangi wtea kei muri o tnei pukapuka, ka ta tohu ai i te tau tmahi.
Tirohia mn e tika ana te raupapatanga o ng whrangi 2 – 19 kei roto i tnei pukapuka, , kore ttahi o aua whrangi i te takoto kau.
ME HOATU RAWA KOE I TNEI PUKAPUKA KI TE KAIWHAKAHAERE TE MUTUNGA O TE WHAKAMTAUTAU.
Te Mtauranga Mat 91391M, 2018
M TE KAIMKA
TMAHI TUATAHI
(a) Whakaotia te ttohi i raro nei hei whakaatu i te ture ttai hanganga, i te ingoa (nahanaha) IUPAC rnei m ia rpoi ngota whaiwaro.
Ture Ttai Hanganga Ingoa (nahanaha) IUPAC
Cl
Cl
O
4-mewaro hparo-tahi owaro
phaukini pwaro (propanamide)
(b) I h te tapa i ng ptara e toru, , he w kanokore rerek kei roto i ia ptara. E mhiotia ana ng w kanokore e toru ko te:
hparo-tahi pwaro CH3CH2CH2CH2CHO
waikawa pwaro waih-kore phaumota CH3CH2CH2CH2COCl
Hangaia he htepe hei tautohu i ia w kanokore e toru m te whakamahi anake i ng whakahohe e whai ake:
• wai
• ng mtakinga e hono ana ki ng momo kei roto
• te momo tauhohenga kei te puta
• ng ture ttai hanganga o ng hua whaiwaro.
2
M TE KAIMKA
QUESTION ONE
(a) Complete the table below to show either the structural formula or the IUPAC (systematic) name for each organic molecule.
Structural Formula IUPAC (systematic) name
Cl
Cl
O
4-methylhexanal
propanamide
(b) Three bottles, each containing a different colourless liquid, have been incorrectly labelled. The three colourless liquids are known to be:
pentanal CH3CH2CH2CH2CHO
pentan-1-ol CH3CH2CH2CH2CH2OH
pentanoyl chloride CH3CH2CH2CH2COCl
Develop a procedure to identify each of the three colourless liquids using only the following reagents:
• water
Your procedure should include:
• the type of reaction occurring
• structural formulae of any organic products.
4
M TE KAIMKA
ANAKE
(c) He C4H8O3 te ttai rpoi ngota o te X t mhiotia, , ka puta ng tauhohenga e whai ake:
• Ka tauhohe a X ki te mehanga konutai pkawa waro hei whakaputa i te hauh.
• Ina whakaweratia a X ki te konurehu konukita-rua i whakawaikawatia, ka huri te tae mai i te karaka ki te kkriki, engari kore te hua e tauhohe ki te mehanga Benedict.
• He tauhohenga tangohanga ka puta i a X me te waikawa pungatara kuk kia puta ai ng hua whaiwaro e rua.
E ai ki ng mhiohio i runga ake, ttuhia te ttai hanganga o X T Mhiotia.
Parahautia t ttai hanganga o X, me:
• ng ture ttai hanganga o ng hua whaiwaro
• ttahi whakamramatanga o ng hua nui, iti hoki pea ka puta.
Ttai hanganga m X T Mhiotia:
6
(c) Unknown X has the molecular formula C4H8O3 and undergoes the following reactions:
• It reacts with sodium carbonate solution to release carbon dioxide gas.
• When X is heated with acidified potassium dichromate, the colour changes from orange to green, but the product does not react with Benedict’s solution.
• X undergoes an elimination reaction with concentrated sulfuric acid to produce two organic products.
Based on the information above, draw the structural formula of Unknown X.
Justify your structural formula of X, including:
• structural formulae of any organic products
• an explanation of any major and minor products.
Structural formula for Unknown X:
7
M TE KAIMKA
TMAHI TUARUA
(a) E whakaaturia ana te ttai hanganga o te 2,3-hparo-tahi pwaro waih-rua, ko ttahi ingoa an ko te hparo-tahi nonireka (glyceraldehyde), i raro.
H C
H C OH
Ka taea e te hparo-tahi nonireka te noho hei poinanaha whakaata (poinanaha mata).
(i) Ttuhia ng poinanaha whakaata o te hparo-tahi nonireka ki te tapawh i raro nei.
(ii) Whakamramahia he aha i taea ai e te hparo-tahi nonireka te noho hei poinanaha whakaata.
(iii) Me phea te wehewehe i ng poinanaha whakaata e rua o te hparo-tahi nonireka?
Whakamramatia t tuhinga.
(a) The structural formula of 2,3-dihydroxypropanal, more commonly known as glyceraldehyde, is shown below.
H C
(i) Draw the enantiomers of glyceraldehyde in the box below.
(ii) Explain why glyceraldehyde can exist as enantiomers.
(iii) How could the two enantiomers of glyceraldehyde be distinguished?
Explain your answer.
M TE KAIMKA
ANAKE
(b) Hangaia ai ng ptini-rua (dipeptide) mai i ng waikawa amino e rua e honoa ana e ttahi hononga phaukini (ptini). Ka mahia te ptini-rua e whakaaturia ana i raro mai i te kairni (glycine) me te aranina (alanine):
CH C
C CH2H2N
(i) Porowhitatia te hononga phaukini (ptini).
(ii) Whakatauritea ng whakapheko -wai waikawa me te kawakore o te ptini-rua o runga ake.
Me whakauru ki t tuhinga:
• ttahi whakamramatanga o te tauhohenga whakapheko -wai
• ng ttai hanganga o ng hua ka puta mai i te whakapheko -wai waikawa me te kawakore o te ptini-rua, ki ng tapawh e rua kua tukuna.
Whakapheko -wai waikawa:
Whakapheko -wai kawakore:
10
(b) Dipeptides are made from two amino acids joined by an amide (peptide) bond. The dipeptide shown below is made from glycine and alanine:
CH C
C CH2H2N
(i) Circle the amide (peptide) bond.
(ii) Compare and contrast the acidic and basic hydrolysis of the above dipeptide.
Your answer should include:
• an explanation of the hydrolysis reaction
• structural formulae of the products formed when the dipeptide undergoes acidic and basic hydrolysis, in the two boxes provided.
Acidic hydrolysis:
Basic hydrolysis:
M TE KAIMKA
(c) Ko te ttai hanganga o te hporo-tahi pwaro he:
H
O CH3 CH2 CH2 C
Hangaia he mahere tauhohe hei tahuri i te hporo-tahi pwaro ki te hporo-rua pwaro.
M ia upane me whakauru:
• ng whakahohe me ng huatanga
• te ttai hanganga o te hua whaiwaro i muri i ia upane.
12
H
Devise a reaction scheme to convert butanal into butanone.
For each step include:
• the reagents and conditions
13
M TE KAIMKA
TMAHI TUATORU
Ka taea te waikawa khuka te whakamahi hei mahi i te waikawa khuka-rau (PGA), he hkawa-rau e whakamahia ana hei mahi i ng tuitui whakarewa. E whakaaturia ana te hanganga o te waikawa khuka i raro nei.
HO – CH2 – COOH
(a) (i) Ki te tapawh i raro, ttuhia he whanga o te mekameka waerau PGA hei whakaatu i ng wae truarua e TORU.
(ii) Tautohua, whakamramahia hoki te momo tauhohenga kei te puta i te hanganga o te PGA.
(b) He maha ng tauhohenga ktui whaiwaro e whakarewahia ana i raro i te rerenga whakamuri (reflux).
(i) Ki te tapawh i raro, ttuhia te ttai hanganga me te ingoa o te hkawa ka puta mai i te whakawera i te waih ewaro me te waikawa pwaro i raro i te rerenga whakamuri i roto i te waikawa pungatara kuk.
Ingoa:
QUESTION THREE
Glycolic acid can be used to make polyglycolic acid (PGA), a polyester used to make dissolvable stitches. The structure of glycolic acid is shown below:
HO – CH2 – COOH
(a) (i) In the box below, draw a section of the PGA polymer chain to show THREE repeating units.
(ii) Identify and explain the type of reaction occurring in the formation of PGA.
(b) Many organic synthesis reactions are heated under reflux.
(i) In the box below, draw the structural formula and name the ester formed from heating ethanol and butanoic acid under reflux in the presence of concentrated sulfuric acid.
Name:
M TE KAIMKA
ANAKE
(ii) Mai i ng hoahoa i raro, tuhia te tau o te taputapu ka whakamahia m te whakawera i raro i te rerenga whakamuri.
1 2 3
(iii) Tuhia ng painga o te whakawera i raro i te rerenga whakamuri m te whakareri i te hkawa i te whanga (i).
(iv) Mai i ng hoahoa i runga, tuhia te tau o te taputapu ka whakamrama i te tukanga ka taea te whakamahi hei horoi (wehe) i te hkawa i te whanga (i) mai i te ranunga tauhohenga.
16
(ii) From the diagrams below, give the number of the apparatus used for heating under reflux.
1 2 3
(iii) Outline the advantages of heating under reflux in the preparation of the ester in part (i).
(iv) From the diagrams above, give the number of the apparatus and explain the process that could be used to purify (separate) the ester in part (i) from the reaction mixture.
17
M TE KAIMKA
ANAKETAU TMAHI
He whrangi an ki te hiahiatia. Tuhia te (ng) tau tmahi mn e tika ana.
18
19
Extra paper if required. Write the question number(s) if applicable.
Level 3 Chemistry, 2018 91391 Demonstrate understanding
of the properties of organic compounds
2.00 p.m. Thursday 15 November 2018 Credits: Five
Achievement Achievement with Merit Achievement with Excellence Demonstrate understanding of the properties of organic compounds.
Demonstrate in-depth understanding of the properties of organic compounds.
Demonstrate comprehensive understanding of the properties of organic compounds.
Check that the National Student Number (NSN) on your admission slip is the same as the number at the top of this page.
You should attempt ALL the questions in this booklet.
A periodic table is provided in the Resource Booklet L3–CHEMR.
If you need more room for any answer, use the extra space provided at the back of this booklet and clearly number the question.
Check that this booklet has pages 2 – 19 in the correct order and that none of these pages is blank.
YOU MUST HAND THIS BOOKLET TO THE SUPERVISOR AT THE END OF THE EXAMINATION.
9 1
3 9
1 M