Unit 17, 18 & 19 - Groups in the Periodic Table/ Rates of Reaction/ Heat Energy Changes in Chemical Reactions Flashcards
What and the group 1 elements called
Alkali metals
Give 2 properties of alkali metals that are different to normal metals
Low melting points, soft and easy to cut
What happens to alkali metals when they are burned in air
They are oxidised
Which way does the reactivity of alkali metals go?
More reactive further down
Why are alkali metals with more shells more reactive
It is easier for the electron to be lost
What are group 7 elements called
Halogens
What type of molecules do halogens exist as
Diatomic
Why do halogens need to be handled with care
They are toxic and corrosive
What does chlorine look like
A green has
What does iodine look like
Purple/ black solid
What does bromine look like
Brown liquid
What is formed when a halogen reacts with metals
Salts with halide ions
Give a halide salt and what it is used for
Sodium chloride, table salt
Why can all halogens be used as disinfectants and bleaches
They kill microorganisms and remove colour
What is the test for chlorine
Turns damp blue litmus paper red then bleached
What is formed when halogens react with hydrogen
Hydrogen halides which form an acid
How is HCl acid made
Hydrogen gas and chlorine gas react to form hydrogen chloride, when dissolved in water, the ions disassociate so the H+ ions make it an acid
Which way are the halogens more reactive
As you go up the table
How can the order of halogens be worked out
Using displacement reactions
Why do halogens with less shells react more
It is easier to gain an electron
What is a redox reaction
When a reaction has oxidation and reduction
What are group 0 elements called
Noble gases
Give 3 properties of noble gases
Colourless
Low melting points
Poor conductors
What is a unique property of noble gases
Inert, don’t react easily