Properties and uses of different kinds of steel
3 marks · NormalExplain why stainless steel is more suitable than mild steel for kitchen sinks. Your answer should mention at least two properties of each material.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
Stainless steel is more suitable because it does not rust or corrode due to the chromium content forming a protective oxide layer. Mild steel is strong and malleable, but it rusts easily when in contact with water and air, making it unsuitable for wet conditions like a kitchen sink.
Also accept: Accept mentions of resistance to corrosion, ease of cleaning, inability to rust for stainless; rusting and strong/malleable for mild steel.
Common mistakes: Only giving one property per material.; Not mentioning corrosion/rust.
Show mark scheme and worked solution
Marking points
M1 · 1 mark · Mentions stainless steel resists rust/corrosion due to chromium/oxide layer.
B1 · 1 mark · Mentions mild steel rusts easily/is prone to corrosion with water and air.
B2 · 1 mark · Gives a second correct property for each material (e.g. ease of cleaning for stainless; strong or malleable for mild steel).
Worked solution
Stainless steel is chosen for kitchen sinks because its chromium content makes it very resistant to corrosion and rust, even when constantly wet. It is also easy to clean and durable. Mild steel, while strong and malleable, will rust quickly when exposed to water, making it unsuitable for a sink.