C2 H - Sample set 1 Q6
6) This question is about properties of materials.
(a) Figure 6 shows some properties of steel and Kevlar®.
(a) Figure 6 shows some properties of steel and Kevlar®.
Body armour, such as a bullet-proof vest, could be manufactured using either of these materials.
Explain two reasons why Kevlar® is preferred to steel as the material for body armour. (4)
(b) The use of nanoparticles has increased in recent years. (i) The length of one side of a cube of silver is 2cm as shown in Figure 7.
Explain two reasons why Kevlar® is preferred to steel as the material for body armour. (4)
(b) The use of nanoparticles has increased in recent years. (i) The length of one side of a cube of silver is 2cm as shown in Figure 7.
surface area to volume ratio = ..............................................................
(ii) Suggest an explanation of why a given mass of silver is more effective as a catalyst when used as nanoparticles rather than in a powder form. (3)
(Total for Question 6 = 10 marks)
(Total for Question 6 = 10 marks)