This question is about glass and polymers.
Beakers can be made from soda-lime glass or poly(ethene). Table 1 shows information about these materials.
| Property | Soda-lime glass | Poly(ethene) |
|---|---|---|
| Temperature at which softening/melting begins (∘C)(^\circ\text{C})(∘C) | 700 | 115 |
| Flammability | Does not burn | Burns |
| Resistance to impact | Shatters | Tough |
| Cost of one beaker | £1.20£1.20£1.20 | £1.80£1.80£1.80 |
Suggest two reasons why a Bunsen burner should not be used to heat a liquid in a poly(ethene) beaker. Use Table 1.
Poly(ethene) beakers are more expensive than soda-lime glass beakers. Suggest one reason why using poly(ethene) beakers instead of soda-lime glass beakers could save a science department money over time. Use Table 1.
Ethene (C2H4)(\text{C}_2\text{H}_4)(C2H4) is polymerized to make poly(ethene). The displayed formula of ethene is:
HH\/C =C/\HH\begin{array}{cc} \text{H} & \text{H} \\ \backslash & / \\ \text{C} & \!\!=\text{C} \\ / & \backslash \\ \text{H} & \text{H} \end{array}H\C/HH/=C\H
Which of the following structures represents the repeating unit of poly(ethene)?
Structure A: [HH∣∣−C−C−∣∣HH]n\left[ \begin{array}{cc} \text{H} & \text{H} \\ | & | \\ -\text{C} & -\text{C}- \\ | & | \\ \text{H} & \text{H} \end{array} \right]_nH∣−C∣HH∣−C−∣Hn
Structure B: [HCH3∣∣−C−C−∣∣HH]n\left[ \begin{array}{cc} \text{H} & \text{CH}_3 \\ | & | \\ -\text{C} & -\text{C}- \\ | & | \\ \text{H} & \text{H} \end{array} \right]_nH∣−C∣HCH3∣−C−∣Hn
Structure C: [ClH∣∣−C−C−∣∣HH]n\left[ \begin{array}{cc} \text{Cl} & \text{H} \\ | & | \\ -\text{C} & -\text{C}- \\ | & | \\ \text{H} & \text{H} \end{array} \right]_nCl∣−C∣HH∣−C−∣Hn
Many ethene molecules join together to form poly(ethene). Which two words describe an ethene molecule in this polymerization process?