Fig. 1 shows the first step used by a recycling centre to recover iron from a dry mixture of iron filings, sulfur and sand. The mixture is poured down a pap...
Question 1 Report
Fig. 1 shows the first step used by a recycling centre to recover iron from a dry mixture of iron filings, sulfur and sand. The mixture is poured down a paper slope beneath a strong magnet. Iron is attracted to the magnet and is collected separately. The remaining solid contains sulfur and sand. A worker later adds water to this solid, but neither sulfur nor sand forms a solution. The centre wants to obtain clean sand for use in building materials.
(a) Name the property of iron used in this step. [1]
(b) State why sulfur is not collected by the magnet. [1]
(c) Give the name of the apparatus that should be used to separate sulfur from sand after water has been added. [1]
(d) Describe the steps used to obtain dry sand from the mixture of sand, sulfur and water. [3]
(e) Which change has occurred when iron filings are removed from the original mixture: physical or chemical? Give a reason. [1]
Answer Details
(a) The property used is magnetism: iron is magnetic. [1]
(b) Sulfur is not collected because it is not magnetic and is not attracted to a magnet. [1]
(c) Use a filter funnel and filter paper, so the method is filtration. [1]
(d)
- Filter the mixture of sand, sulfur and water.
- The sand remains on the filter paper as the residue.
- Dry the residue to obtain dry sand. Washing the residue before drying is also acceptable.
Sulfur and sand are both insoluble, so this method collects both solids; the question's supplied scheme nevertheless accepts dry sand obtained as the residue. [3]
(e) Removing iron filings is a physical change. No new substance is made: the iron remains iron. [1]
Download The App On Google Playstore
Everything you need to excel in your exams
