Combustion and enzymes

How does fractional distillation separate hydrocarbons?

• according to their fractions

• Separates different hydrocarbons because they are different types

• by melting and boiling pointrs

• according to how hot they are

What is the difference between alkanes and alkenes

• alkanes are acidic

• alkenes are acidic

• alkenes have a carbon carbon double bond

• alkanes have a carbon carbon double bond

Name 2 conditions needed for cracking to take place

• high temperature and a catalyst

• a catalyst and an enzyme

• enzymes and high temperatures

• a catalyst

What are the products of incomplete combustion

• carbon dioxide and water and methane

• carbon dioxide and water

• water and carbon monoxide

• carbon monoxide, water, carbon and carbon dioxides

When will incomplete combustion take place

• when there isn't enough oxygen available to completely oxidise the hydrocarbon

• when there is too much oxygen available to completely oxidise the hydrocarbon

• during anaerobic respiration in humans

• during short bursts of exercise

Proteases break down proteins, in which conditions do they work best

• neutral

• pH 7

• pH 2-4

• pH 8-12

Lipases are enzymes - what is the substrates they break down and the products they make

• proteins into amino acids

• lipids into glucose

• Starch into glucose

• Lipids into fatty acids and glycerol

why do carbohydrases like amylase not work in the stomach

• they only break down carbohydrates like starch

• they only work in neutral conditions

• they only work in acidic conditions

• they dont break down proteins

what does the term denature mean

• the enzyme does not work

• The substrate changes shape so the enzyme no longer speeds up the reaction

• The active site changes shape so the substrate no longer fits with the active site and the enzyme no longer speeds up the reaction

what is the function of bile

• to neutralise the enzymes

• to neutralise stomach acid and increase surface area of lipids prior to digestion

• emulsify fats

• denature enzymes