Percentage Of Copper In A Brass Alloy: Analysis
Unit Name: Analysis at Work Unit Number: G621
Assignment Title: Finding the Percentage of Copper in a Brass Alloy
Assignment: G620 Sample Assignment C
Date Set: Due Date:
Assessment Objective(s): AO3
Vocational Brief:
Brass is an alloy of copper and zinc. This alloy has many uses ranging from coinage to non-ferrous fittings on ships. Many domestic taps use brass where contact with water occurs. You are provided with a sample of brass which is about 150 years old and you are asked to quantitatively analyse it, using colorimetry, to find the percentage of copper present. Your results will be used to compare the composition of antique brass with modern brass.
Task:
Finding the Percentage of Copper in a Brass Alloy
The …show more content…
Use your graph to measure the concentration of copper ions in your ‘brass’ solution. The value that you obtain will give you the mass of copper in your ‘brass solution’.
15. Use this value to calculate the percentage of copper in your antique brass sample.
G621: Analysis at Work – Sample Assignment C
Finding the Percentage of Copper in a Brass Alloy
Technicians’ Guidance:
Please read this guidance before issuing the practical.
Calibration
• Copper sulphate 0.1 mol dm-3 can be used – as indicated in experimental details Assignment C.
• However, Cu(NO3)2 (aq) rather than CuSO4 could be used in the calibration in case of a colour difference of the hydrated copper ions in the two solutions.
Antique Brass
• Small brass screws can be used (washed with alcohol / acetone and dried).
• 1.5 g will give a concentration of about 1 g / 250 cm3, which fits onto the graph.
Reaction with Nitric Acid
• Note that the brass takes time to dissolve.
• It is the responsibility of the Centre to ensure that correct health and safety regulations are adhered to. Please refer to www.cleapss.org.uk for further details.
• Ratio 1:1 HNO3 : H2O could be used, but it is advisable that the teacher completes
Assignment Title: Finding the Percentage of Copper in a Brass Alloy
Assignment: G620 Sample Assignment C
Date Set: Due Date:
Assessment Objective(s): AO3
Vocational Brief:
Brass is an alloy of copper and zinc. This alloy has many uses ranging from coinage to non-ferrous fittings on ships. Many domestic taps use brass where contact with water occurs. You are provided with a sample of brass which is about 150 years old and you are asked to quantitatively analyse it, using colorimetry, to find the percentage of copper present. Your results will be used to compare the composition of antique brass with modern brass.
Task:
Finding the Percentage of Copper in a Brass Alloy
The …show more content…
Use your graph to measure the concentration of copper ions in your ‘brass’ solution. The value that you obtain will give you the mass of copper in your ‘brass solution’.
15. Use this value to calculate the percentage of copper in your antique brass sample.
G621: Analysis at Work – Sample Assignment C
Finding the Percentage of Copper in a Brass Alloy
Technicians’ Guidance:
Please read this guidance before issuing the practical.
Calibration
• Copper sulphate 0.1 mol dm-3 can be used – as indicated in experimental details Assignment C.
• However, Cu(NO3)2 (aq) rather than CuSO4 could be used in the calibration in case of a colour difference of the hydrated copper ions in the two solutions.
Antique Brass
• Small brass screws can be used (washed with alcohol / acetone and dried).
• 1.5 g will give a concentration of about 1 g / 250 cm3, which fits onto the graph.
Reaction with Nitric Acid
• Note that the brass takes time to dissolve.
• It is the responsibility of the Centre to ensure that correct health and safety regulations are adhered to. Please refer to www.cleapss.org.uk for further details.
• Ratio 1:1 HNO3 : H2O could be used, but it is advisable that the teacher completes