1. What was the purpose of testing the known compounds?1 pointThe purpose of testing the known compounds was to observe the substance's atomic emission spectrum.The purpose of testing the known compounds was to determine the characteristic flame color of each of the substancesThe purpose of testing the known compounds was to predict the identity of the unknown compoundsThe purpose of testing the known compounds was to determine exactly how much of each element the substance contained
Question
- What was the purpose of testing the known compounds?1 pointThe purpose of testing the known compounds was to observe the substance's atomic emission spectrum.The purpose of testing the known compounds was to determine the characteristic flame color of each of the substancesThe purpose of testing the known compounds was to predict the identity of the unknown compoundsThe purpose of testing the known compounds was to determine exactly how much of each element the substance contained
Solution
The purpose of testing the known compounds was multi-fold:
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To observe the substance's atomic emission spectrum: This is done to understand the wavelengths of light that a particular element emits. This is unique to each element and can be used as a 'fingerprint' to identify the element.
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To determine the characteristic flame color of each of the substances: When a substance is heated, the electrons get excited and jump to higher energy levels. When they fall back to their original levels, they emit light of a specific color. This color is characteristic of the element and can be used to identify it.
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To predict the identity of the unknown compounds: By comparing the emission spectrum and flame color of the unknown compound with those of known compounds, one can predict the identity of the unknown compound.
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To determine exactly how much of each element the substance contained: This can be done by comparing the intensity of the emission lines in the spectrum. The intensity of the line is proportional to the amount of the element present in the substance.
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