Photo AI
An analyst determines the concentration of calcium ions in a city's water supply using Atomic Absorption Spectroscopy (AAS) as the analytical tool - VCE - SSCE Chemistry - Question 1 - 2005 - Paper 1
Question 1
An analyst determines the concentration of calcium ions in a city's water supply using Atomic Absorption Spectroscopy (AAS) as the analytical tool. A simplified diag... show full transcript
Worked Solution & Example Answer:An analyst determines the concentration of calcium ions in a city's water supply using Atomic Absorption Spectroscopy (AAS) as the analytical tool - VCE - SSCE Chemistry - Question 1 - 2005 - Paper 1
Step 1
What particular characteristic is needed by the lamp providing the light source S?
Answer
The lamp providing the light source S must emit light at a specific wavelength that corresponds to the electronic transition of calcium ions (Ca²⁺). This characteristic ensures that the light can be absorbed effectively by calcium ions in the sample, allowing for accurate analysis through Atomic Absorption Spectroscopy.
Step 2
What happens to the Ca²⁺ ions introduced into X? Explain your answer.
Answer
When the sample containing Ca²⁺ ions is introduced into X, the calcium ions will absorb the specific wavelength of light emitted by the lamp in source S. This causes excitation of the electrons in the Ca²⁺ ions. As the excited electrons return to their ground state, they release energy in the form of light. The intensity of this emitted light is then detected in the subsequent stage (Y) and measured, which is proportional to the concentration of calcium ions in the original water sample.