Spectra

Question 1

How do we excite electrons?

Answer 1

1.Spark
2.Heat
3.light

Question 2

Electron Orbit + Bohrs Discovery.

Answer 2

1. Electrons orbit the nucleus in fixed energy levels and at a fixed distance from the nucleus.
2. Electrons that orbit shells further from the nucleus exist at higher energy levels.
3. If energy is absorbed, the electrons jump to an “excited state” and if the energy is removed the electrons will move to their ground state.
4. This results in a photon being emitted( A light particle with no mass or charge).

Question 3

What does the absorption spectrum and emission spectrum show?

Answer 3

The absorption spectrum displays dark lines or gaps in the spectrum of which the gas has absorbed corresponding to wavelength.

The emission spectrum has coloured lines in the spectrum corresponding to the wavelengths of the electromagnetic radiation emitted by the gas.

The energy absorbed or emitted in the electron transfer of a given element are unique for that element hence the line spectrum is also unique. It is like the finger print of the element,

Note: The energy absorbed by the electron to go from ground state to excited state is equal to the energy released by the electron upon returning from excited state to ground state.

Question 4

Flame Test info:

Answer 4

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1. Flame Test
Analytical technique that relies on the unique nature of an element’s emission spectrum to identify its presence in a mixture or compound.

Platinum metal wire is dipped into a solution of the unknown element’s salt. When placed near Bunsen burner, the heat of the flame excites electrons in the vapourised metal ions of the salt. When these excited electrons return to ground state, they emit light of specific wavelengths, producing characteristic colours = flame colour.

Flame colour = indicates metal ion present in the salt

Question 5

What is AAS:

Answer 5

Atomic Absorption Spectroscopy

It is an analytical technique that relies on unique nature of an elements absorption spectrum to identify its Prescence and concentration in a mixture.

AAS works as an element in the gaseous phase can absorb only certain specific wavelengths of light called absorption spectrum.