yr 10 science notes

Question 1

What are the three main subatomic particles that make up an atom?

Answer 1

Protons, neutrons, and electrons

Protons and neutrons form the nucleus, while electrons orbit in electron shells.

Question 2

Where are protons and neutrons located in an atom?

Answer 2

In the nucleus

Electrons are located in electron shells around the nucleus.

Question 3

What is the charge and mass of an electron?

Answer 3

Charge: -1, Mass: 1/1840

The mass of an electron is negligible compared to protons and neutrons.

Question 4

What is the atomic number?

Answer 4

The number of protons in an atom

It determines the type of element.

Question 5

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

Answer 5

Subtract the atomic number from the atomic mass

Atomic mass is the total number of protons and neutrons.

Question 6

What are protons and what is their charge?

Answer 6

Subatomic particles with a positive charge (+1)

Protons have a mass of 1 atomic mass unit.

Question 7

What determines the type of atom?

Answer 7

The number of protons

For example, 2 protons = helium, 6 protons = carbon.

Question 8

What are neutrons and what is their charge?

Answer 8

Subatomic particles with no charge

Neutrons have a mass of 1 atomic mass unit.

Question 9

What is an isotope?

Answer 9

Atoms with the same number of protons but different number of neutrons

Isotopes have the same atomic number but different mass numbers.

Question 10

What is the charge and mass of an electron?

Answer 10

Charge: -1, Mass: 1/1840

Almost all of the mass of an atom is in the nucleus.

Question 11

What is electron configuration?

Answer 11

The arrangement of electrons in shells around the nucleus

Electrons fill up from the inner shell first.

Question 12

How many electrons can the first shell hold?

Answer 12

2 electrons

The second shell can hold 8 electrons, and the third shell can hold up to 18 electrons.

Question 13

What is the shorthand electron configuration of silicon?

Answer 13

2, 8, 4

Silicon has 14 electrons total.

Question 14

What is the outermost electron shell called?

Answer 14

Valence shell

It can hold a maximum of 8 electrons.

Question 15

What are valence electrons?

Answer 15

Electrons in the valence shell

They largely determine the chemical properties of an element.

Question 16

True or False: The number of electrons in an atom equals the number of protons.

Answer 16

True

This means atoms have no overall charge.

Question 17

What is the mass number of an atom?

Answer 17

The total number of protons and neutrons

It is different from the atomic number.