Higher November 2019 Paper 3 Q13
13 Liquid A and liquid B are mixed together in the ratio 2 : 13 by volume to make liquid C.
Liquid A has density 1.21 g/cm3
Liquid B has density 1.02 g/cm3
A cylindrical container is filled completely with liquid C.
The cylinder has radius 3 cm and height 25 cm.
Work out the mass of the liquid in the container.
Give your answer correct to 3 significant figures.
You must show all your working. (4)
| Answer | Mark | Mark scheme |
|---|---|---|
| 739 | P1 | process to find the volume of C, eg \(\pi \times 3^2 \times 25\) (= 706.8583471 or \(225\pi\)) |
| P1 | process to find the volume of A or the volume of B, eg \(\text{``}706.8\ldots\text{''} \times \dfrac{2}{2 + 13}\) (= 94.24777961 or \(30\pi\)) or \(\text{``}706.8\ldots\text{''} \times \dfrac{13}{2 + 13}\) (= 612.6105675 or \(195\pi\)) or process to work with density and ratio, eg \((2 \times 1.21 + 13 \times 1.02)\ (= 15.68)\) | |
| P1 | process to find the mass of C, eg \(\text{``}30\pi\text{''} \times 1.21\ (= 114.0398133) + \text{``}195\pi\text{''} \times 1.02\ (= 624.8627788)\) or \(\text{``}225\pi\text{''} \times \text{``}15.68\text{''} \div (2 + 13)\) | |
| A1 | for an answer in the range 738.5 to 739 |
Additional guidance
For use of 3.14
Volume of C is 706.5
Volume of A is 94.2
Volume of B is 612.3
Mass of A is 113.982
Mass of B is 624.546
Do not award accuracy mark if the figure is from obvious incorrect working