Atomic structure

Question 1

what are all substances made up of?

Answer 1

atoms

Question 2

what is a substance with only one sort of atom?

Answer 2

an element

Question 3

what is the definition of an atom?

Answer 3

it is the smallest piece of an element that can exist

Question 4

when is a molecule formed?

Answer 4

when atoms join together by chemical bonds

Question 5

what is the relative mass, relative charge and position of a proton?

Answer 5

relative mass: 1
relative charge: +2
position: in the nucleus

Question 6

what is the relative mass, relative charge and position of a neutron?

Answer 6

relative mass: 1
relative charge: 0
position: in the nucleus

Question 7

what is the relative mass, relative charge and position of a electron?

Answer 7

relative mass: 1/1836
relative charge: -1
position: in the shells around nucleus

Question 8

what is the atomic (proton) number?

Answer 8

the number of a protons

Question 9

what is the mass (nucleon) number?

Answer 9

the number of protons + the number of neutrons

Question 10

what are isotopes?

Answer 10

different atoms of the same element containing the same number of protons but different number of neutrons in their nuclei

Question 11

what is the relative atomic mass?

Answer 11

an average value that takes account of the abundance of the isotopes of the element

Question 12

How do you calculate the relative atomic mass of an element (or Ar) from isotopic abundances?

Answer 12

RAM (average mass) = mass of isotopes A x % of isotopes A + mass of isotopes B x % of isotopes B/ 100