Chemistry

Question 1

How do atomic mass and number relate to neutrons, protons and electrons?

Answer 1

The atomic number represents the number of electrons and protons.
The atomic mass represents the number of protons and neutrons in the nucleus of an atom.

Question 2

What are families and periods in the periodic table?

Answer 2

Families/Groups are the vertical columns. They go from 1-18
Periods are the horizontal rows. They go from 1-7

Question 3

What is the difference between ionic bonding and covalent bonding?

Answer 3

Ionic bonding occurs between a metal and a non-metal while covalent bonding occurs between two non-metals. Additionally, in an ionic bond atoms exchange electrons while in a covalent bond, atoms share electrons.

Question 4

What is an atom?

Answer 4

The smallest unit of matter cannot be broken down chemically. An atom also has no electrical charge as it has the same amount of protons and electrons.

Question 5

What is a nucleus?

Answer 5

The nucleus is the centre of an atom. It is made up of protons and neutrons.

Question 6

What is a proton?

Answer 6

A proton is a subatomic particle with a positive charge. +1

Question 7

What is a neutron?

Answer 7

A neutron is a subatomic particle with zero charges.

Question 8

What is an electron?

Answer 8

An electron is a subatomic particle with a negative charge. -1. It moves around the nucleus in shells.

Question 9

What is a valence shell?

Answer 9

A valence shell is the outermost shell of an atom.

Question 10

What is a pure substance?

Answer 10

A pure substance is a form of matter with the same chemical composition throughout.

Question 11

What is an element?

Answer 11

An element is made up of just one atom and it cannot be broken down chemically.

Question 12

What is an ion?

Answer 12

An ion has an electrical charge. It has a different number of protons and neutrons. An ion can be positively charged or negatively charged by either taking away electrons or adding electrons.

Question 13

What is a metal?

Answer 13

The elements left of the staircase are metals. Metals are solid at room temperature (Except Mercury), have luster, can conduct electricity, malleable, and ductile.

Question 14

What is a non-metal?

Answer 14

The elements right of the staircase is non-metals. Non-metals are typically gases, sometimes solids or liquids. Additionally, they lack luster, cannot conduct electricity (most elements cannot), and are not ductile or malleable.

Question 15

What is a periodic table?

Answer 15

The periodic table is a system for organizing chemical elements. It arranges the elements by their atomic number, 1-118.

Question 16

What are alkali metals?

Answer 16

Alkali metals are the first group of the periodic table. They are very reactive in water.

Question 17

What are alkali earth metals?

Answer 17

Alkali earth metals are the second group of the periodic table. They are metals that can be found in the crust of the earth.

Question 18

What are metalloids?

Answer 18

Metalloids are found in the staircase of the periodic table. They have properties of both metals and non-metals. Metalloids can be shiny or dull and can conduct electricity, but they are not malleable or ductile.

Question 19

What are halogens?

Answer 19

Halogens are the 17th group of the periodic table. They are non-metals and are very reactive.

Question 20

What are noble gases?

Answer 20

Noble gases are the 18th group of the periodic table. They are not reactive as their valence shell is full.

Question 21

What are compounds?

Answer 21

A compound is a substance made from two or more elements by chemical means.

Question 22

What are molecules?

Answer 22

A molecule is formed when two or more atoms of an element are chemically joined.

Question 23

What is a Bohr model?

Answer 23

A Bohr model is a diagram that shows the number of electrons in each shell of an atom. There are 7 shells in each atom that holds a different maximum number of electrons. 2, 8, 8, 18, 18, 32, 32.

Question 24

What is a chemical formula?

Answer 24

A chemical formula is a formula that shows how many atoms of a particular element are found within a compound.

Question 25

What is a subscript?

Answer 25

A subscript is a number that comes after a chemical symbol. It tells us the number of atoms of the element.

Eg. CaCl₂ there is 1 calcium atom and 2 chlorine atoms

Question 26

What is ionic bonding?

Answer 26

When atoms gain electrons from other atoms or lose electrons from other atoms, it is forming an ionic bond. An ionic bond occurs between a non-metal and a metal. The non-metal receives/takes electrons from the metal. Therefore the metal gets a positive charge while the non-metal gets a negative charge. They then combine to make a compound.

Question 27

What is covalent bonding?

Answer 27

Covalent bonding occurs between two non-metals. The electrons are shared which makes the particles of the compound neutral. Neutral particles made of atoms that are joined by a covalent bond is called a molecule.