Topic 3: What are elements?

Question 1

What is the difference between Laws vs Theories?

Answer 1

• Laws explain what happens
• Theories explain why

Question 2

What are the three types of subatomic particles?

Answer 2

• Electron
• Proton
• Neutron

Question 3

What subatomic particles are in the nucleus and what are their charges

Answer 3

Proton - Positively charged
Neutron - Neutral charge

Question 4

Describe what Thompson believed of the atom

Answer 4

• “Raisin bun model”
• Positively charges mass with negatively charged particles embedded

Question 5

Describe what Rutherford believed of the atom

Answer 5

• “Planetary model”
• Nucleus has positively charged atoms called protons
• Nucleus has mass
• Most of the atom is empty space
• Electrons rotate around the atom like planets around a sun

Question 6

Describe what Bohr believed of the atom

Answer 6

• Electrons rotate around the nucleus in fixed shells
• Nucleus has protons and neutrons

Question 7

What is the electron cloud model

Answer 7

• Electrons act like waves
• Their location cannot be calculated, only where they are most likely to be

Question 8

What does the atomic number represent?

Answer 8

Number of protons and electrons in an atom

Question 9

How can you find the number of neutrons in an atom?

Answer 9

Atomic mass - Atomic number = Number of neutrons

Question 10

What is an ion and how it is made?

Answer 10

An ion is an atom that is no longer neutral
Ions are made when an atom gains or loses electrons

Question 11

What is an anion?

Answer 11

An atom that has gained an electron during a chemical reaction, and is now negatively charged

Question 12

What is a cation?

Answer 12

An atom that has lost an electron during a chemical reaction, and is now positively charged