Using materials (chemistry only)

Question 1

Easy

Polymers are widely used to manufacture lightweight orthotic leg braces for medical rehabilitation.

Table 1 shows some key physical and mechanical properties of two candidate polymers, Polymer X and Polymer Y.

Table 1

Property	Polymer X	Polymer Y
Density in $g/cm3\text{g/cm}^3$	1.05	1.40
Melting point in $∘C^\circ\text{C}$	165	260
Stiffness (Elastic Modulus)	Low	High
Moisture absorption	Low	High

An orthotic leg brace must be lightweight (to minimize patient fatigue), highly rigid/stiff (to provide proper structural support), and hygienic (having low moisture absorption to prevent sweat buildup and skin irritation).

Using the data in Table 1, decide which polymer (Polymer X or Polymer Y) is best suited for each of the following criteria:

Density (to keep the brace lightweight)
Stiffness (to provide structural support)
Moisture absorption (to ensure hygiene)

[3]

A heavy-duty bionic orthotic brace fabricated from Polymer Y has a mass of 4.8 kg.

Calculate the mass of a brace with the exact same dimensions if it were fabricated from Polymer X.

Use the information in Table 1 and the equation:

\text{mass of Polymer X brace} = \frac{\text{density of Polymer X}}{\text{density of Polymer Y}} \times \text{mass of Polymer Y brace}

[3]

Using materials (chemistry only)

Question 1

Table 1

Using materials (chemistry only) Questions

Using materials (chemistry only)

Question 1

Table 1

Using materials (chemistry only) Questions