Periodic table

Question 1

How do you calculate the number of neutrons in an element?

Answer 1

Mass number - atomic number = Number of neutrons

Question 2

What charge do protons , neutrons and electrons have?

Answer 2

Protons have +1
Neutrons have 0
Electrons have -1

Question 3

Is going horizontal in the periodic table a period or group?

Answer 3

Period

Question 4

Is going vertical in the periodic table a period or group?

Answer 4

Group

Question 5

How do we rank elements?

Answer 5

Today we rank elements by their atomic number (number of protons in an atom’s nucleus).

Question 6

What are the 3 sub-atomic particles?

Answer 6

Protons , electrons and neutrons

Question 7

Are there metals or non-metals in the periodic table?

Answer 7

Metals

Question 8

Where are metals found in the periodic table?

Answer 8

On the left side of the periodic table

Question 9

What are the properties of noble gases?

Answer 9

~Inert - They do NOT gain or lose electrons because they have a full outer shell. Noble gases can be used as light bulbs because they are unreactive

~Monatomic - Noble gases are unreactive, they exist as single atoms instead of forming molecules.

~Low boiling point - But their boiling points do increase as you move down the periodic table. This is because the relative atomic mass increases lower down the periodic table.

~Low density - Their densities do increase as you move down the periodic table because of their increasing relative atomic mass.

~Colourless

Question 10

What are the properties of halogens?

Answer 10

~7 Outer electrons - When they react , they gain 1 electron to get a full outershell when they gain , the ions become negative.

~Diatomic molecules - In their form, halogens share electrons to make diatomic molecules

~Salt - When the metal atom transfers its outer electron to a non-metal atom , salt is formed(The result is a compound where all the ions have a full outer shell.)

~Reactivity decreases - As you go down they decrease because atoms gain more electron shells and the distance between the outer electron and nucleus increases which makes the attraction decrease

Question 11

Where are halogens in the periodic table?

Answer 11

Halogens are elements in Group 7 in the periodic table.

Question 12

Why are halogens very reactive?

Answer 12

Halogens have 7 electrons in their outer shell. They are very reactive because they easily accept an electron into this outer shell.

Question 13

When halogens react, they gain 1 electron to get a full outer shell. By gaining 1 electron, halogens form a __________ ion.

Answer 13

Negative

Question 14

Which alkali metal is the least reactive and what is its features?

Answer 14

Lithium
~Its electron structure is (2,1)
~Burns with crimson flames when it reacts with oxygen
~Floats on the surface of water and will release bubbles of hydrogen gas (it effervesces).

Question 15

What is sodium’s features?

Answer 15

~Its electron structure is (2,8,1)
~More reactive because its outer electron is less strongly attracted to the positively charged nucleus. This is because it is a greater distance from the positive charge of the atom’s nucleus.
~Burns with a yellow/orange flame when it reacts with oxygen.
~Moves quickly across the surface of the water and melts

Question 16

What is potassium’s features?

Answer 16

~Its electron structure is (2,8,8,1)
~More reactive because its outer electron is least strongly attracted to the nucleus
~More vigorous, water and metal reaction compared with sodium
~Burns with a lilac flame when it reacts with oxygen.

Question 17

Alkali metal reacting?

Answer 17

~Reacting with water - metal floats on the surface and melts to create a metal hydroxide
~Reacting with chlorine - A metal chloride is formed dissolves in water to give a colourless solution
~Reacting with oxygen - Rapidly turns from silvery shiny to dull as a metal oxide

Question 18

When sodium is put in water, the metal ______ on the surface and reacts to form sodium ____________.

Answer 18

Floats , hydroxide

Question 19

Many non-metal elements form diatomic molecules which are molecules made up of pairs of atoms.
Describe
by name the THREE elements that are not in group 7 that form diatomic molecules.

Answer 19

Hydrogen , nitrogen and oxygen

Question 20

Why are some elements displaced during a reaction?

Answer 20

Less reactive halogens can be displaced by more reactive halogens from compounds. In other words, it takes the place of the less reactive element.

Question 21

How many elements are there in the periodic table?

Answer 21

118 elements

Question 22

In group 1 elements , why do the elements get more reactive as you go down?

Answer 22

The outer electron is further from the nucleus, making it easier to lose.

Question 23

True or false!
The colour of the group 7 elements gets darker as you go down ?

Answer 23

True!

Question 24

How is the reactivity when you go down group 0

Answer 24

There is no reactivity because they are gasses!