Chemistry EBIs

What I got wrong and why

Polymers

• When drawing alkenes, remember to count number of bonds per carbon and to put in a double bond! There should only be a max of 4 bonds per carbon
• Alkene general formula CnH2n
• Alkane general formula is CnH2n+2
• Features of a homologous series include the same chemical properties, trend or same functional group. Don't say they have the same reactivity.
• BE SPECIFIC in your answers. When you say there's a trend, say there's a trend in terms of physical properties and they have similar chemical properties.

Reactions

• Reaction between hydrogen and air is 2H2 + O2  > 2H2O
• Rust can be prevented also by covering in plastic

Ions

• Ammonium is not the same as ammonia! Ammonium has a formula of NH4  while ammonia is NH3  !!
• Test for ammonium ions: add NaOH solution, warm, test gas with damp red litmus and it should turn blue.
• Test for chloride ions: add silver nitrate solution and dilute nitric acid, which should form a white precipitate.
• When blue litmus turns red in HCl(aq) solution (water), mention that while it does turn red…