Intro to Org Chem

Intro to Org Chem

Test, Write, Apply

Multiple Choice

What does hydrocarbon consist of?

• hydrogen atoms and carbon atoms

• hydrogen ions and carbon ions

• water molecules and carbon atoms

Multiple Select

Which statement accurately describes a homologous series?

(You may choose more than 1 answer.)

• undergoes similar chemical reactions

• different functional group

• same general formula

• same physical properties

Multiple Select

Select the true statements for the gradual change in physical properties of a homologous series as the number of carbon atoms increases

• Flammability increases

• Melting/Boiling points increases

• Viscosity increases

• Density increases

Gradual Change in Physical Properties

• When number of carbon atoms increases -> bigger size of molecules

• 1. Flammability decreases (Harder to combust, smokier flame)

• 2. Melting/Boiling Points increases

• 3. Viscosity increases (harder for liquid to flow)

• 4. Increase in density (more atoms in each molecule)

Multiple Select

Comparing the structures of alkanes and alkene, how are they similar?

• same general formula

• identical naming prefix

  (eth-, prop-, but-...)

• contained carbon-carbon double bond

• same functional group

• they are hydrocarbons

Alkane & Alkene

• They are hydrocarbons (contained hydrogen and carbon atoms).

• They have the same naming system according to the number of carbon atoms.

Multiple Select

Comparing the structures of alkanes and alkene, how are they different?

• different general formula

• identical naming prefix

  (eth-, prop-, but-...)

• alkene contained carbon-carbon double bond while alkane does not have.

• same functional group

• they are hydrocarbons

Alkane Vs Alkene

• 1. Different General Formula: Alkane - C_nH_2n+2 VS Alkene - C_nH_2n

• 2. Different functional group: Alkene - carbon-carbon double bond

Petroleum

• Mixtures of hydrocarbons

  (mainly alkanes)

• How do we separate the different fractions of petroleum?

  
  

Open Ended

What is a petroleum?

Multiple Choice

Since petroleum is a mixture of hydrocarbons of different boiling points, we can use ____________ to separate the fractions.

• simple distillation

• filtration

• crystallisation

• fractional distillation

Fraction Distillation

• 1. Heat in furnace to form vapours

• 2. Vapours pass through fractionating tower

• 3. Petroleum gas is collected at the top of the tower

• 4. The other vapours cool and condense at the same time at different levels of the tower

• 5. The one with lower boiling points are collected at the top while the one with higher boiling points are collected at the bottom