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Flashcards in The Chemical Industry Deck (24)
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1

Bonding in nitrogen

Triple bonds between nitrogen atoms

2

How is ammonium formed

Nitrogen has a lone pair of electrons which allows ammonia to act as a base and form dative covalent bonds to hydrogen ions

3

Nitrogen oxide, appearance and origin

Appearance: Colourless gas

Origin: Combustion in vehicle engines, thunderstorms, denitrifying bacteria in soil

4

Nitrogen dioxide, appearance and origin

Appearance: Brown gas

Origin: Oxidation of NO in atmosphere

5

Dinitrogen oxide, appearance and origin

Appearance: Colourless gas

Origin: Denitrifying bacteria in soil

6

Test for nitrate (V) and ammonium ions

Nitrate (V): Add sodium hydroxide and Deverda's alloy (Cu/Al/Zn) and gently heat. If present ammonium gas will be given off

Ammonium: Add sodium hydroxide and heat gently. If present the gas wi turn damp red litmus paper blue

7

What effect does increasing the pressure have on equilibrium

Equilibrium shifts to the side with fewer molecules of gas. This follows Le Chatelier's principle

8

What effect does changing the temperature have on equilibrium

If forwards reaction is exothermic:
Increasing the temperature will shift equilibrium to the right, decrease will shift to the left

If forwards reaction is endothermic:
Increasing the temperature will shift equilibrium to the left, decreasing will shift to the right

9

What effect does using a catalyst have on equilibrium

Does not effect the position of equilibrium, only increases the rate of reaction

10

Ways of measuring rate of reaction

-Measuring volumes of games evolved
-Measuring mass changes
-pH measurement
-Colorimetry
-Chemical analysis including titration

Rate of reaction = Change in property / Time

11

How to find initial rate from a graph

Draw a tangent at t=0 and the find the gradient

12

Rate equation

Rate = k[product]^order

13

The gas constant

8.314

14

The graph of ln(Arrhenius) tells you what

Gradient = Activation energy/Gas constant

Y-intercept = ln(A)

15

How to find the order on a graph

Take a half life. If constant then the reaction is first order

16

What does a flat line on a rate graph sbow

The reaction is zero order

17

What are raw materials

The base materials for a reaction

18

What are feedstocks

The reactants that go into a chemical process

19

Ammonia, feedstocks and raw materials

Feedstocks: methane, air, water

Raw materials: natural gas, air, water

20

Nitric acid, feedstocks and raw materials

Feedstocks: ammonia, air, water

Raw materials: natural gas/oil, air

21

Sulphuric acid, feedstocks and raw materials

Feedstocks: sulphur, air, water

Raw materials: natural gas/oil, air, water

22

Ethanoic acid, feedstocks and raw materials

Feedstocks: methanol, carbon monoxide, water

Raw materials: coal/natural gas, air, water

23

What is a co-product

A product produce in a chemical process which was not desired but is still useful

24

What is a by-product

A waste product produced in a chemical process