Date | May 2022 | Marks available | 3 | Reference code | 22M.2.SL.TZ0.1 |
Level | SL | Paper | 2 | Time zone | no time zone |
Command term | Explain | Question number | 1 | Adapted from | N/A |
Question
Figure 1 shows the rapid increase in global plastics production. Concerns have been raised about the environmental impact as vast quantities of discarded plastics are found in the oceans, like the Great Pacific Garbage Patch (GPGP).
Figure 1: World global plastics production (1950–2015)
Some countries have developed strategies to recover these plastics. These strategies have been more successful in some countries than others. Figure 2 compares the percentage of plastics recovered in European countries.
Figure 2: Plastic – wasted or recovered?
Figure 1: Hannah Ritchie and Max Roser (2018) - “Plastic Pollution”. Published online at OurWorldInData.org. Retrieved from: https://ourworldindata.org/plastic-pollution [Online Resource]. Source: based on Jambeck et al (2015) and
Eriksen et al (2014). Icon graphics from Noun Project. Data is based on global estimates from Jambeck
(2015) based on plastic waste generation rates, coastal pollution sizes, and waste management practices
by country. This is a visualization from OurWorldDate.org, where you will find data and research on how
the world is changing. License under CC-BY-SA by the authors Attribution 4.0 International (CC BY 4.0)
https://creativecommons.org/licenses/by/4.0/ [Accessed 20 April 2020]. Source adapted.
Figure 2: © DEUTSCHE WELLE.
Many governments have introduced legislation to ban single-use plastic straws. As a result many customers have started to use metal straws, see Figure 3.
Figure 3: Different types of straw
Figure 3: s-cphoto / iStock.
State the trend of plastic production between 1950 and 2015.
List two reasons why polyethylene terephthalate (PET) is often used for food packaging.
Outline one reason why products that are made of more than one material can be difficult to recycle.
List two reasons why some countries recycle a larger percentage of plastics than others.
Outline why thermoplastics tend to be easier to recycle than thermosetting plastics.
Explain one negative environmental impact of incinerating plastic waste.
State how the plastic straw gains its stiffness.
Outline one reason why the plastic straw is mass produced.
Outline one appropriate manufacturing method for making the plastic straw.
Explain how market pull has influenced the release of the metal straw.
Markscheme
increasing;
rising;
Award [1] for stating the trend of plastic production between 1950 and 2015.
Award a mark for any appropriate word that describes an increase but do not accept terms such as ‘positive trend’ or ‘improving’.
lightweight;
low cost/cheap;
easily shaped/moulded;
non toxic/food safe;
widely available;
recyclable;
waterproof/non absorbent;
Award [1] for listing each reason why polyethylene terephthalate (PET) is often used for food packaging up to [2 max].
need to be separated;
as they may fall into different recycling categories/have different recycling requirements;
need to be separated;
which can be time/energy consuming/costly;
Award [1] for identifying a reason why products that are made of more than one material can be difficult to recycle and [1] for a development up to [2 max].
Do not award marks across clusters.
government policy/legislation/regulations;
infrastructure/capability/resources/facilities;
public awareness/community driven;
Award [1] for listing each reason why some countries recycle a larger percentage of plastics than others [2 max].
thermoplastics have a linear chain structure/weak secondary bonds;
which allows them to be heated/melted and reformed/reshaped;
thermosetting plastics have cross-linked chains/strong secondary bonds;
which make them difficult to be heated/melted and reformed/reshaped;
Award [1] for identifying why thermoplastics tend to be easier to recycle than thermosetting plastics and [1] for a development up to [2 max].
Do not award marks across clusters.
incineration results in toxic chemicals being released into the atmosphere;
resulting in pollution/harmful emissions;
leading to health issues/damage to plants and wildlife;
incinerating plastic waste requires high energy usage;
which utilises fossil fuels;
leading to high carbon emissions/climate change/global warming/depletion of finite resources;
Award [1] for each distinct point in an explanation of one negative environmental impact of incinerating plastic waste up to [3 max].
Do not award marks across clusters.
cylindrical shape;
wall thickness;
Award [1] for stating how the plastic straw gains its stiffness up to [1 max].
straws are high consumption/disposable/single-use items;
creating demand for the product from retailers/consumers;
large consumer base / target audience / target market;
allows for benefits derived from economies of scale;
Award [1] for identifying a reason why the plastic straw is mass produced and [1] for a development up to [2 max].
Do not award marks across clusters.
extrusion;
allows for production be made quickly/in high volume;
Award [1] for identifying an appropriate manufacturing method for making the plastic straw and [1] for a development up to [2 max].
a new idea is needed as a result of demand from the marketplace;
due to a greater awareness of the negative impact of plastic on the environment;
resulting in consumer pressure for eco friendly alternatives to single use plastic products;
Award [1] for each of three distinct points in an explanation of how market pull has influenced the release of the metal straw up to [3 max].
Examiners report
A straightforward graph reading question. Most students found this easy but a small percentage did not express their answer using clear language.
A list two question. Quite straightforward with most students able to achieve 1 or 2 marks.
Quite straightforward with most students able to achieve 1 or 2 marks.
Another list two question. Quite straightforward with most students able to achieve 1 or 2 marks.
Most students were able to achieve at least one mark with a few achieving two. Most attained a mark from the second line of the first cluster.
A question that allowed students to achieve 1 or 2 marks although only a few achieved 3. The most common responses related to the first cluster, but responses were not always well structured. Some candidates included cross cluster responses.
A question most candidates struggled with as there was possibly some confusion caused by the stem and images/discussion of both metal and plastic straws. Very few achieved the one mark.
Quite a straightforward question. Most candidates achieved at least one mark, with the most common responses identifying 'demand' for the product.
A very challenging question for candidates which showed a poor understanding of how plastic straws would be manufactured. Many wrote about injection moulding, blow moulding and some about 3D printing. Very few achieved any marks at all for this question. This question was similar to Q1e(i) from May 2021 about carbon reinforced plastics which was also poorly answered.
Many candidates answered this with relevant points although again responses were not always well structured. This question was a good discriminator. Almost all candidates were able to achieve at least one mark, a number were able to achieve 2 but very few achieved 3. Some similarity on responses compared to 1d(i) relating to 'demand'.