Topic 10 - Group 7, the halogens

INTRODUCTION TO GROUP 7

• Each of these elements only need one more electron to complete its outer shell. 
• They are good oxidising agents. 
•  The ability to attract electrons is known as electronegativity. Fluorine is the most electronegative element. The alkali metals are the most electropositive, they lose electrons.

FLUORINE

• Pale yellow gas, which has an irratating smell and is very poisonous. 
• Reacts with almost everything. 
• It will accept electrons from every element above it in the series. 
• Fluorine will displace chlorine from chlorides.

BROMINE

• Occurs widely, but in small quantities. 
• Manufactured by using the principle that chlorine is lower in the activity series.
• Deep-red, fuming liquid at room temperature. 
• Slightly solule in water.
• More soluble in organic solvents such as carbon tetrachloride. 

Test for a bromide

Make…