CI 1 Flashcards
What conditions are needed for making ammonia?
Iron catalyst
High pressures
High temperature (450C)
Why is a nitrogen molecule very unreactive?
Triple bond
High bond enthalpy
Ammonia (gas) formula
NH3
What bonds does an ammonia molecule have?
1 lone pair
3 N-H single bonds
What does the lone pair in ammonia do?
Allows it to form dative covalent bonds
Allows it to act as a base
To form an ammonium ion
Ammonium ion formula
NH4+
Equation to convert ammonia to ammonium
NH3 + H+ = NH4+
What bonds do ammonium ions have?
1 dative bond
3 single bonds
What color is NO?
Colorless gas
What color is NO2?
Brown gas
What color is N2O?
Colorless gas
Where does nitrogen (IV) oxide come from?
Formed from oxidation of NO in the atmosphere
Where does dinitrogen (I) oxide come from?
Formed in the soil by denitrifying bacteria
What happens to nitrate ions when oxygen levels are low?
anaerobic bacteria reduce them to nitrogen
NO3- -> NO -> N2O -> N2
Nitrate (V) formula
NO3-
What is the formula for nitrite?
NO2-
Aka nitrate (III)
What is the equation for the formation of the nitrate (III) ion?
NH4+ + 1.5O2 -> NO2- + 2H+ + H2O
What is the equation for the formation of the nitrate (V) ion?
Further oxidation from the nitrate (III) ion
NO2- + 0.5O2 -> NO3-
How do we test for ammonium ions?
1) add sodium hydroxide
2) heat gently
3) Ammonia should be given off
How do we test for nitrate (V) ions?
1) add sodium hydroxide
2) add Devarda’s alloy
3) heat gently
4) damp red litmus paper turns blue
Test for ammonia gas?
- Strong smell
- Red litmus turns blue
- white fumes with hydrogen chloride gas from HCL
How do you conduct the brown ring test to test for nitrate ions?
-Add iron sulfate
-Add concentrated sulfuric acid
-Watch for a brown ring in the test tube
What is the bond shape and angle of an ammonia molecule?
Pyramidal
107 degrees
What is the bond shape and angles of an ammonium ion molecule?
Tetrahedral
90 degrees
