Practice questions on : atmospheric nitrogen

Question 1

what is the equation to find the speed of light?

Answer 1

speed of light (ms-) = wavelength (m) x frequency (Hz or s-1)

Question 2

what is the equation of energy in terms frequency ?

Answer 2

energy (J) = plank constant x frequency (s -1)

Question 3

80nm is short wavelength radiation. convert this wavelength range to an energy range (J) . step by step

Question 4

for the molecule NH3 explain the bond angle and shape.

the angle and shape

Answer 4

The bond is 107 this is because there is four areas of electrons around the central N atom . 3 bond pairs with hydrogen and one lone pair around the center nitrogen.The electrons arrange themseleves to minimize repulsion.

the shape is called trigonal pyramidal with 107 angle around the nitroge

Question 5

for the moecule N2O state and explain the bond angle and the shap of the molecule,

Answer 5

Two areas of electrons around central N atom. the electrons arranged to minimize repulsion.

thw shape is linear and the angle is 180.

Question 6

Why are levels of NH3 variable in the atmosphere?

Answer 6

Because deposition processes dominate its loss and sources of deposition are diverse

Question 7

what is the main source of ammonia in the atmosphere ?

Answer 7

-main source arise from biological activity such as the decomposition of urea (CH2)2 +co in animal urine by enzymes.
-agriculture, animal husbandry

Question 8

equation for the reaction of compound with water to make ammonia.

Answer 8

(NH2)2) + H2O - 2NH3 + CO2

Question 9

How does ammonia cause a decline in plant growth ?

Answer 9

It forms ammonia sulfate aerosol that when deposited causes a decrease in PH.

Question 10

What is the oxt state of N in NO2- ?

Answer 10

o = ( -2 x 2 ) = -4 N = +3 -4+3= -1

Question 11

what is the oxt state of N ion NH4+ ?

Answer 11

N = -3

Question 12

what is the main way NOx molecules are removed from the atmosphere?

Answer 12

the conversion of HNO3 of NOx molecules with the HO.
NOx + HO. - HNO3

Question 13

how does N2O get into the atmosphere?

Answer 13

• N20 is released to the air from both soils and aquatic system with undistributed soils, cultivated soils and oceans bulk of the sources.
  -The bacteria transfer nitrate to N2 under aerobic conditions
  -N2O escaping to the surface of the ocean

Question 14

How is N20 removed from the atmosphere ?

Answer 14

-N2O is inert in the trosposphere. when the N2O releases stratosphere it is destroyed by the photolysis ( splitting of compound by the photo)
-destroyed by dissolving in ocean by O2

Question 15

what happens in the initiation step ?

Answer 15

-one molecule react with itself to form a radical.
-its a endothemic reaction because the bonds are broken when exposed to the UV light.

ex. CL2 - CL. + CL.

Question 16

what happens in the propagation process?

Answer 16

-A radical reacts with reactant to form a new molecule which keeps the reacton going

ex. CL. + CH4 - CH3. + HCL

Question 17

what happens in the termination step?

Answer 17

• two radical react to form a molecule
• it is an exothermic reaction because the bond is making

ex CH3. + CH4. - C2H6

Question 18

methan reacting wih the chlorine full homolytic process.

Answer 18

-cl2 + HV - cl. + cl.
-cl. + ch4 - hcl + ch3.
-ch3. + cl - ch3cl +cl.
formaions : cl. + cl. = cl2
ch3. + cl. = ch3cl
ch3. + ch3.=c2h6

Question 19

what is homolytic fission ?

Answer 19

-cl2 = cl. + cl.
-one of the 2 shared gos to each the elements

Question 20

what is the hetrolytic fission?

Answer 20

-both shared electrons go to just one of the atom

Question 21

what happens as the temperature increases ( maxwell - boltzmann )

Answer 21

as the temperature increases, more molecules move at higher speeds as the molecule collised with eachother so they have higher kenetic energies.