The Chemical Industry Flashcards
Bonding in nitrogen
Triple bonds between nitrogen atoms
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
Nitrogen oxide, appearance and origin
Appearance: Colourless gas
Origin: Combustion in vehicle engines, thunderstorms, denitrifying bacteria in soil
Nitrogen dioxide, appearance and origin
Appearance: Brown gas
Origin: Oxidation of NO in atmosphere
Dinitrogen oxide, appearance and origin
Appearance: Colourless gas
Origin: Denitrifying bacteria in soil
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
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
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
What effect does using a catalyst have on equilibrium
Does not effect the position of equilibrium, only increases the rate of reaction
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
How to find initial rate from a graph
Draw a tangent at t=0 and the find the gradient
Rate equation
Rate = k[product]^order
The gas constant
8.314
The graph of ln(Arrhenius) tells you what
Gradient = Activation energy/Gas constant
Y-intercept = ln(A)
How to find the order on a graph
Take a half life. If constant then the reaction is first order
