Radioactivity Calculations/Units

Question 1

Speed of light

Answer 1

3x10^8 m/s

Question 2

How do you calculate binding energy in Joules

Answer 2

Energy=Mass(Kg) x (Speed of light)^2

Question 3

How to calculate Mass defect

Answer 3

Mass of component parts (Kg/u) - Mass given in question (Kg/u). If in u, convert to Kg to find binding energy

Question 4

What does t stand for in decay equation

Answer 4

Time elapsed

Question 5

What does No stand for in decay equation

Question 6

Isotope definitely

Answer 6

Different form of the same element with same number of protons but different number of neutrons

Question 7

What does the mass number tell us

Answer 7

Identifies the element

Question 8

What does the atomic mass number tell us

Answer 8

Identifies the isotope of an element

Question 9

Converting years into seconds

Answer 9

x60x60x24x365

Question 10

What is the binding energy per nucleon

Answer 10

The energy required to break down the nucleus into its constituent parts

Question 11

What is the relation between the stability of an isotope and their binding energy/nucleon

Answer 11

The higher the binding energy, the more stable the nucleus.

Question 12

What energy level does Lymaan drop to

Answer 12

Drops to n=1

Question 13

What energy level does Bahmer drop to

Answer 13

N=2

Question 14

What energy level does Peschan drop to

Answer 14

3

Question 15

What spectrum is Lymaan

Answer 15

Ultraviolet

Question 16

What spectrum is Bahmer

Answer 16

Visible light

Question 17

What spectrum is Peschan

Answer 17

Infrared

Question 18

Which of the three energy levels requires the most energy and why?

Answer 18

Lymaan as it takes a lot more energy to drop all the way down to n=1

Question 19

Turning …x10^-7 to nanometres

Answer 19

x10^9

Question 20

E=mc^2 what is c?

Answer 20

Speed of light

Question 21

Stable nucleus

Answer 21

Even number of protons and neutrons
More protons means means more electrostatic repulsion force so more neutrons are needed to stop this.

Question 22

Unstable nucleus

Answer 22

Too many protons and not enough neutrons to stop electrostatic force of repulsion

Question 23

Why radioactive decay occurs

Answer 23

A nucleus is unstable and wants to become more stable so it must get rid of either a proton or a neutron to stabilise it.

Question 24

Proton number

Answer 24

Z

Question 25

Convert lamda to nano meters

Answer 25

X10^9 (-9)

Question 26

Nano to mew(micro)

Answer 26

/1000

Question 27

Plank’s constant

Answer 27

6.63x10^-34

Question 28

Frequency unit

Answer 28

Hz

Question 29

H

Answer 29

Plank’s constant

Question 30

Metres to nano metres

Answer 30

x10^-9

Question 31

Steps for wavelength transition calculations

Answer 31

Energy change, f=e/h, lambda=speed of light/f, convert to nm x10^-9, state spectrum

Question 32

Discrete (whole number) energy levels

Answer 32

Because the electrons in an atom can only occupy certain, specific energy levels or orbitals, so they emit

Question 33

characteristic spectra of elements (frequency and wavelength)

Answer 33

produced when the electrons in an atom or molecule transition between specific energy levels

Question 34

why the visible emission spectrum of hydrogen has only a few lines

Answer 34

Hydrogen has one electron and most transitions