Group 7 and Displacement reactions Flashcards
How many electrons do group 7 elements have on their outermost shell?
7
Group 7 atoms are called
Halogens
As you go down the group
The atomic number increases
The elements are darker
The boiling point is higher (making them go from gas to liquid to solid)
Reactivity
Decreases as you go down the group
Elements are more reactive at the top of the group because
The shell with the missing electron is nearer to the nucleus so the pul from the positive nucleus is greater
Group 7 elements take part in
Displacement reactions
What is a displacement reaction?
It is when a more reactive element “pushes out” (displaces) a less reactive element from a compound
What would you call a redox reaction?
When oxidisation and reduction happen at the same time
Example of a displacement reaction written as a equation (chlorine and potassium iodide –> iodine and potassium chloride)
Cl (aq) + 2KI(aq) –> I (aq) + 2KCL(aq)
2 2
OILRIG
Oxidisation Is Loss Reduction Is Gain
What is a halide?
A Halogen with a metal
Chlorine + potassium bromide –>
(Cl + 2KBr –>)
2
And colours
–> Bromine + potassium chloride
( Br + 2KCl)
2
Orange in water, brown in hexane
Chlorine + potassium iodide –>
(Cl + 2KI –>)
2
And colours
–> Iodine + potassium chloride
( I + 2KCl)
2
Purple in water
