Corrections

Question 1

Shape around carbon in graphene/graphiye

Answer 1

Hexagonal planar layers made of trigonal planar shapes around each C atom with 120⁰ bond angles

Question 2

Carbonate Test

Answer 2

React with dilute strong acid
Products: CO2, H2O, salt
Effervescence due to CO2 production
Confirm bubbles are CO2 with limewater (Ca(OH)2)
–> goes cloudy as CaCO3, a white precipitate, is formed

Question 3

Sulfate Ion Test

Answer 3

Add aqueous Ba ions

Ba 2+ –> SO4 2- –> BaSO4 (white precipitate)

Question 4

Halide ion test

Answer 4

Add aqueous Ag+ ions
Ag 1+ + X 1- –> AgX

AgCl - white, soluble in dilute NH3
AgBr - cream, soluble on conc. NH3
AgI - yellow, insoluble in NH3

Question 5

Ammonium ion test

Answer 5

React with warm NaOH
Forms NH3
Use moist indicator paper to confirm NH3 presence- turns blue

Question 6

What causes E/Z isomerism?

Answer 6

Rigid position of pi bond’s electron density above and below sigma bond
Causes restricted rotation aound double bond

Question 7

CIP Priority Rules for E/Z

Answer 7

Group with higher Ar and Mr given higher priority

Question 8

Cis-Trans Isomerism

Answer 8

When 2 of the substituent groups attached to each C atom are hydrogens
Cis = same side, trans = opposite