atomic structure

Question 1

define an atom

Answer 1

The smallest particle of an element that can exist on its own - atoms of the same element have the same number of protons

Question 2

define an element

Answer 2

The simplest kind of substance that consists of only 1 type of atom and cannot be broken down into anything simpler

Question 3

draw a diagram of the structure of an atom

Question 4

what is the relative mass, charge and location of the 3 main subatomic particles

Answer 4

relative mass charge location
proton 1 +1 nucleus
neutron 1 0 nucleus
electron 1/1836 (negligible) -1 electron cloud shells

Question 5

define an isotope

Answer 5

isotopes = atoms of the same element (therefore same no. of protons) but a different number of neutrons therefore different mass numbers.

Question 6

similarities and differences of isotopes of the same element

Answer 6

similarities
- same no of protons
- therefore same atomic number
- similar chemical properties

differences
- different number of neutrons
- therefore different mass number
- different physical properties

Question 7

define relative atomic mass

Answer 7

relative atomic mass = the weighted avg of the mass of all the naturally abundant isotopes of an element relative to 1/12 the mass of Carbon-12 atom

Question 8

explain how relative atomic mass is different from mass number

Answer 8

The relative atomic mass of an element is the weighted average mass of its atoms, considering the abundance of isotopes. It accounts for the presence of different isotopes in nature. In contrast, the mass number is the total number of protons and neutrons in an atom’s nucleus and is a whole number specific to an isotope, not accounting for isotopic abundance - it’s simple the no. protons + no. neutrons.

Question 9

what is the purpose of a mass spectrometer?

Answer 9

Used to determine the % composition (relative abundance) and relative atomic (isotopic) masses of a sample of isotopes - used to differentiate the different isotopes

Question 10

what is the order of the steps of mass spectrometry

Answer 10

vapourisation -> ionisation -> acceleration-> deflection -> detection