atomic structure

Question 1

what are all elements made of?

Answer 1

• atoms

Question 2

what are atoms?

Answer 2

• the smallest part of an element that can exist

Question 3

what are atoms made of?

Answer 3

• three types of subatomic particles
• protons, neutrons and electrons

Question 4

what do electrons have?

Answer 4

(-1) charge

Question 5

what do electrons do?

Answer 5

• wizz around the nucleus in orbitals, which take up most of the volume of the atom

Question 6

where is most of the mass of the atom concentrated?

Answer 6

• in the nucleus

Question 7

what is the nucleus?

Answer 7

• where you find the protons and neutrons

Question 8

why is relative mass and relative charge used?

Answer 8

• because the mass and charge of the subatomic particles is really small

Question 9

what is the relative mass of a proton?

Answer 9

1

Question 10

what is the relative mass of a neutron?

Answer 10

1

Question 11

what is the relative mass of an electron?

Answer 11

1/1840

Question 12

what is the relative charge of a proton?

Answer 12

+1

Question 13

what is the relative charge of a neutron?

Answer 13

0

Question 14

what is the relative charge of an electron?

Answer 14

-1

Question 15

why is the mass of the electrons not included when calculating the mass of the atom?

Answer 15

• the mass of electrons is negligible compared to the mass of protons and neutrons

Question 16

what can you use to figure out the number of protons, neutrons and electrons in an atom?

Answer 16

• the nuclear symbol

Question 17

what is the mass number?

Answer 17

• the total number of protons and neutrons in the nucleus of an atom

Question 18

what is the atomic proton number?

Answer 18

• the number of protons (and electrons) in the atom
• it identifies the element
• all atoms of the same element have the same number of protons

Question 19

why is the atomic number sometimes left out of the nuclear symbol?

Answer 19

• you don’t really need it because the element’s symbol tells you its value

Question 20

what happens for neutral atoms which have no overall charge?

Answer 20

• the number of electrons is the same as the number of protons

Question 21

how do you work out the number of neutrons?

Answer 21

mass number - atomic number (top - bottom in the nuclear symbol)

Question 22

how do atoms form ions?

Answer 22

• by gaining or losing electrons

Question 23

what do ions have?

Answer 23

• different numbers of protons and electrons

Question 24

what do negative ions have?

Answer 24

• more electrons than protons

Question 25

what do positive ions have?

Answer 25

• fewer electrons than protons

Question 26

what are isotopes?

Answer 26

• atoms with the same number of protons but different number of neutrons

Question 27

what decides the chemical properties of an element?

Answer 27

• the number and arrangement of electrons

Question 28

why do isotopes have the same chemical properties?

Answer 28

• they have the same configuration of electrons

Question 29

why do isotopes have slightly different physical properties?

Answer 29

• because physical properties depend more on the mass of the atom