Atomic Theory

Question 1

Atomic number and mass number definition and equations

Answer 1

Atomic number- number of protons in an element Mass number- (atomic weight) number of neutrons + number of protons Equation of number of neutrons Mass number- atomic number = no. of neutrons Protons=electrons Protons= atomic no. Protons+neutrons=mass Eg) helium- atomic number=2 Mass no. =4 4-2=2 2 neutrons

Question 2

Isotope definition

Answer 2

Atom with the same atomic number but a different number of neutrons and therefore, has a different mass number

Question 3

What do electron shells represent?

Answer 3

Electrons shells represent levels of energy surrounding the nucleus and can only fit certain numbers of electrons

Question 4

_ _ _ _ _ _ _ _ _ _ of an element are determined by _ _ _ _ _ _ _ _ Configuration

Answer 4

Properties Electron

Question 5

Periodic table groups definition

Answer 5

Arranged in Columns Group numbers represent the number of electron shells Numbers are written in Roman numerals Eg) I - alkaline metals (reactive) II- alkaline earth metals VI- Chalogens VII- halogens VIII- nobal, gases (unreactive)

Question 6

Periodic table periods definition

Answer 6

Arranged in rows Period number represents the number of electrons in the outer shell

Question 7

Atom definition

Answer 7

Atom- building blocks of all matter. Comprised of a nucleus containing protons and neutrons with electrons arranged in shells outside the nucleus.

Question 8

Element definition

Answer 8

Made up of only one type of atom Eg) sodium contains atoms which all have 11 protons

Question 9

Compound definition

Answer 9

Made up of two or more elements chemically combined together eg) NaCl, Fe2O3, CO2

Question 10

Molecule definition

Answer 10

Contains two or more non-metal atoms bonded together They may be different atoms and in H20 or the same type of atom like 02.

Question 11

3 types of nuclear radiation caused by radioactive elements and the extent of damage they cause to humans

Answer 11

Alpha rays (not dangerous unless eaten) Beta rays (only dangerous at close range) Gamma rays (causes damage to human DNA cells - causes tumour/cancer)

Question 12

Difference between stable and unstable isotopes

Answer 12

Stable isotopes- 12C, 238U Unstable isotopes- 14C, 235U Unstable isotopes->radioactive isotope-> radioisotope Unstable isotopes- break apart on their own eg) 14C = 50 of these Unstable isotopes- break apart when hit eg) 235U = 2000 of these When hit with subatomic particles such as protons and neutrons, it can cause damage to human cells,and easily pass through human tissue

Question 13

Half life definitions

Answer 13

Half life= time taken for half of the sample to decay

Question 14

2D structure of an atom

Answer 14

Question 15

Voltage in series and parallel circuits

Answer 15

Question 16

Current in series and parallel circuits