Chemical Synthesis

Question 1

Calculate the cell voltage produced by the hydrogen fuel cell under acidic conditions

Answer 1

1.23V

Question 2

If tempertaure is increased during the Haber process, will the reactant or product be favoured?

Answer 2

Reactant

Question 3

Define what a reaction pathway is

Answer 3

A series of reactions that leads to the formation of the desired product.

Question 4

In the Haber process, in which direction does the the equilibrium shift if the pressure is increased?

Answer 4

Right

Question 5

Give the names of the three different categories of biofuels

Answer 5

First, second and third generation biofuels

Question 6

Is the haber process endothermic or exothermic?

Answer 6

Exothermic

Question 7

How many principles of Green Chemistry are there?

Answer 7

12

Question 8

List the 2 ways ethanol can be synthesised

Answer 8

Fermentation and hydration of ethene

Question 9

Hydration of ethene is produced through the __________ ___________ of products from crude oil

Answer 9

Catalytic cracking

Question 10

List the requirements for fermentation.

Answer 10

Glucose from suitable grain, or fruit. Yeast. Constant temp (37 degrees) absence of air

Question 11

Name an enzyme that can be used as a biological catalyst in the production of biodiesel.

Answer 11

Lipase

Question 12

True or False. Both hydrogen fuel cells in acidic or basic conditions convert H2 & O2 into water.

Answer 12

True

Question 13

Name the two main processes used for synthesising ethanol

Answer 13

Fermentation, hydration of ethene

Question 14

True or False? Glycerin is a by-product of the production of biodiesel via transesterification of vegetable oil.

Answer 14

True

Question 15

Name the two methods that can be used to synthesise biodiesel

Answer 15

base-catalysed and lipase-catalysed methods

Question 16

What are Biofuels?

Answer 16

Fuels produced from plants, algae or animal waste

Question 17

The process of converting one ester to another ester is called _________________

Answer 17

Transesterification

Question 18

What does the contact process produce?

Answer 18

Sulphuric acid

Question 19

True or false. A fuel cell is type of galvanic cell

Answer 19

True

Question 20

What does the Haber process produce?

Answer 20

Ammonia

Question 21

What do the twelve principles of green chemistry aim to reduce?

Answer 21

Waste, energy use, environmental impacts, risks & hazards

Question 22

What is the formula to calculate theoretical atom economy?

Answer 22

(Molar mass of desired product x moles of product/Molar mass of all reactants x moles of reactants) x 100

Question 23

What is biodiesel made from?

Answer 23

Triglycerides (fatty acids) and a short chained alcohol (eg methanol)

Question 24

What is the Haber compromise?

Answer 24

Finding a temperature and pressure that produces enough Ammonia in adequate time without excessive costs or risks. 200atm at 450 degrees C

Question 25

What is steam reforming?

Answer 25

Production of hydrogen from fossil fuels

Question 26

What the name for the synthetic process used to synthesise sulfuric acid

Answer 26

Contact process

Question 27

What is the formula for the Haber Process?

Answer 27

N2(g) + 3H2(g) <-> 2NH3(g)

Question 28

What type of fat is vegetable oil?

Answer 28

Triglyceride

Question 29

What is the formula to calculate experimental atom economy?

Answer 29

Mass of desired product/Mass of all products x 100

Question 30

When designing an optimal synthetic pathway there is a most often a competition between 2 factors. What are they?

Answer 30

The yield of product and the rate of formation of product

Question 31

When producing Biodiesel from a trigylceride, what are the two products?

Answer 31

An ester and Gylcerol

Question 32

Write the formula for the fermentation of glucose

Answer 32

C6H12O6(aq) -> 2C2H5OH(aq) + 2CO2

Question 33

Why is vanadium oxide used as a catalyst in the production of sulphuric acid?

Answer 33

Increases the rate of reaction

Question 34

Why is water not added directly to sulphur trioxide in the contact process?

Answer 34

This would lead to an uncontrolled reaction. So the sulphur trioxide is added to sulphuric acid first before adding the water.

Question 34

Write the equation for the half reaction that occurs at the anode in a hydrogen fuel cell under acidic condictions

Answer 34

2H2 -> 4H+ + 4e-

Question 34

Write the equation for the half reaction that occurs at the cathode in a hydrogen fuel cell under alkaline conditions

Answer 34

O2 + 2H2O + 4e -> 4OH-