General

Question 0

Gamma rays and X-rays are at the UV part of spectrum and have …….

Answer 0

Short wavelengths and high frequency

Question 1

An increasing wavelength = a decrease in …..

Answer 1

Frequency and energy

Question 2

Microwaves and radio waves are at the IR part of the spectrum and have…..

Answer 2

Long wavelengths.

Question 3

Do X-rays or microwaves have more energy?

Answer 3

X-rays have more energy and shorter wavelengths

Question 4

Spectroscopy is defined as….

Answer 4

Techniques where matter is exposed to radiation and the pattern of absorption, transmission or reflection of radiation by the matter is measured and inturpretted.

Question 5

Spectroscopy is the….

Answer 5

Study of interaction or radiated energy and matter.

Question 6

The speed of light, c, in a vacuum is….

Answer 6

3.00 x 10 ^8 m s -1

Question 7

Plancks constant, h, in eV is….

Answer 7

4.14 x 10^-15 eV Hz^-1

Question 8

Plancks constant, h, in J s is….

Answer 8

6.63 x 10^-34 J s

Question 9

Light of a single wavelength is…

Answer 9

Monochromatic

Question 10

Light of many diff wavelengths, white light, is….

Answer 10

Polychromatic.

Question 11

A photon is a form of light absorbed by…..

Answer 11

An atom or molecule.

Question 12

The visible spectrum, in nm, ranges from…..

Answer 12

A wavelength of 400 nm (violet) to 700 nm (red)

Question 13

Spectroscopy can obtain information about (3)…..

Answer 13

Atomic an molecular energy levels
Chemical bonds
Molecule interactions

Question 14

Matter absorbs visible light which gives rise to…..

Answer 14

Colour.

Question 15

A shorter wavelength = higher energy =

Answer 15

Larger transitions.

Question 16

700 nm = (m)

Answer 16

7.00 x 10^-7 m

Question 17

Absorption of red wavelengths, gives rise to….

Answer 17

A green colour.

Question 18

Absorption of blue wavelengths, gives rise to….

Answer 18

Orange colour

Question 19

Absorption of purple wavelengths, gives rise to….

Answer 19

Lime/yellow colour

Question 20

By studying absorption of photons by a molecule, in a certain range of wavelengths, it’s absorption….

Answer 20

Fingerprint can be identified.

Question 21

Obtains over 90% of…..

Answer 21

Astronomical data.

Question 22

Stella composition can be determined by….

Answer 22

IR, visible and UV-Visible spectroscopy

Question 23

In black bodies, radiation and matter are….

Answer 23

In thermal equilibrium.

Question 24

The equation for calculating temp of astronomical objects....

Answer 24

T = 2.90 x 10^-3 m K / wavelength max

Question 25

Wein's constant is...

Answer 25

2.90 x 10^-3 m K

Question 26

Red objects are.....

Answer 26

Cooler temps

Question 27

Blue/white objects are.....

Answer 27

Hotter temps

Question 28

In astronomy, the distance between the source and the detector....

Answer 28

Can be huge.

Question 29

Most of the universe is composed of....

Answer 29

Hydrogen.

Question 30

Equation to calculate wavelength from energy....

Answer 30

Wavelength = hc / E Where E is in eV, Plancks constant is used in eV.

Question 31

Why are Balmer lines weak (low intensity) in stars of low temp?

Answer 31

Low temp = low energy, most transitions are in the lyman series.

Question 32

Why are Balmer lines weak (low intensity) in stars of high temp?

Answer 32

Hydrogen may be fully ionised. Most transitions will be in the paschen series. Higher temp = higher energy.

Question 33

Energy is inversely proportional the wavelength which means....

Answer 33

Shorter wavelengths have greater energy (X-rays) and longer wavelengths have lower energy (microwave)

Question 34

Absorption moves up the n series, where as emission....

Answer 34

Moves down the n series.

Question 35

Equation for light as photons...

Answer 35

E = hf

Question 36

Equation for light as waves...

Answer 36

C= f / wavelength

Question 37

The strength of spectral lines can determine the...

Answer 37

Temp of an object.

Question 38

Difference between uv and vis spec and IR and Raman spec....

Answer 38

In uv and vis the energy is high enough for electrons to move from one energy level to another - electron transitions. In IR the energy is too low to displace molecules but can cause other transitions, rotational or vibrational.