Date | May 2021 | Marks available | 2 | Reference code | 21M.2.SL.TZ0.2 |
Level | SL | Paper | 2 | Time zone | no time zone |
Command term | Outline | Question number | 2 | Adapted from | N/A |
Question
Outline why polypropylene (PP) is used as a material for a cell/mobile phone case.
Describe the difference between a thermoplastic and a thermosetting plastic.
Markscheme
ability to be moulded;
into the shape of the case;
toughness;
ability to withstand impact/protects the mobile phone if dropped;
lightweight;
has little effect on the overall weight (of the phone);
elasticity;
ease of putting the case on and off the mobile phone;
recyclability;
as it is a thermoplastic;
available in a range of colours/textures/styles;
to provide customer choice;
low cost;
making it affordable/easy to replace;
mass production;
making suitable for economies of scale;
Award [1] for identifying why polypropylene (PP) would be used as a material for a cell/mobile phone case and [1] for a brief explanation up to [2 max].
Do not award marks across different clusters.
a thermoplastic has weak secondary bonds/can be heated and shaped repeatedly/can be recycled/cannot withstand high temperatures;
a thermosetting plastic has strong secondary bonds/can be shaped only once/cannot be recycled/can withstand high temperatures;
Award [1] for a definition of a thermoplastic and [1] for a definition of a thermosetting plastic up to [2 max].
Examiners report
Again, a number of cross cluster responses in an accessible question that gave candidates numerous opportunities to achieve 1-2 marks. Many candidates wrote 2 correct points, sometimes more, but not always in a corresponding cluster.
Most candidates knew the difference between thermo and thermoset plastics, but many incorrectly described the process of heating as 'melting'. Most candidates achieved 1-2 marks.