topic 17- groups of the periodic table (1, 7 and 0) Flashcards
Group one elements are also referred to as what?
Alkali metals
What is lithium’s electronic configuration?
2,1
What colour flame does lithium produce when reacted with oxygen?
crimson
What is sodium’s electronic configuration?
2,8,1
Why do the elements become more reactive as you go down group one?
As you go down the group, the electron on the outer shell gets further away from the positively charged nucleus. This causes it to be less strongly attached to the nucleus as you go down the group. So, they become more reactive as it’s easier to break the force of attraction between the outer electron and the nucleus as due to it being further away from the nucleus the force of attractions weaker. Therefore it is easier for the outer electron to be lost.
What flame does sodium burn when reacted with oxygen?
Yellow/orange
What is potassium’s electronic configuration?
2,8,8,1
What flame does potassium burn when it reacts with oxygen?
Lilac
How do the elements in group 1 react with chlorine?
A metal chloride is formed (e.g sodium chloride), which dissolves water to give a colourless solution
How do the elements in group 1 react with water?
The metal floats on the surface and melts to create a metal hydroxides
How do elements in group 1 react with oxygen?
Rapidly turns from silvery shiny to dull as a metal oxide is produced
What happen when lithium (group 1) reacts with water?
It floats in the surface of the water and will release bubbles of hydrogen gas (it effervesces)
How does potassium react with water?
The hydrogen produced by the reaction ignites instantly and the metal also sets alight, sparking, and burning with a lilac flame
What happens when sodium reacts with water?
Sodium fizzes rapidly and melts to form a ball that moves around on the water surface
What happens when lithium reacts with water?
Lithium fizzes steadily and floats, becoming smaller until it eventually disappears
Write out the word equation for a metal reacting with water:
metal + water —> metal hydroxide + hydrogen
What are the elements in group 7 also known as ?
Halogens
How many electrons on the outer shell do elements in group 7 have?
7 electrons
Halogens are diatomic molecules, what does diatomic mean?
Molecules made up of pairs of atoms
What colour is iodine at room temperature?
Dark grey
What state is iodine at room temperature?
Solid
What colour is bromine at room temperature?
Red-brown
What state is bromine at room temperature?
Liquid
What colour is chlorine at room temperature?
Pale green
What state is chlorine at room temperature?
Gas
Method for testing for chlorine:
- insert damp litmus paper into a test tube containing a gas
- if the gas is chlorine, the litmus paper will bleach and change colour from red to white
What colour will the litmus paper change/bleach to if the gas is chlorine?
White
Why do halogens become less reactive as you go down the group?
The electron to be gained from another element is further form the nucleus
What is another name for group 0?
Noble gases
Why are elements in group 0 unreactive?
Because they have a full outer electron shell. They do not lose or gain electrons to create a full shell as it is already full.
Why are noble gases used in light bulbs?
As due to them being inert they will not react with the hot metal filament
Are not noble gases:
-monatomic
-diatomic
why is this?
Noble gases are monatomic as they are unreactive so they exist as single atoms instead of forming molecules
