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1.
Halftime - The time taken for the radioactivity of a specified isotope to fall to half its original value.
2.
Oxygen2- has 8 protons, 10 neutrons, 10 electrons
3.
226Ra decays into 222Rn
4.
Moles = 0.0111
5.
-417kJ/mol
6.
(gmol-1) gram per mole or, Mass of one mole of a compound
7.
x = 4 for the H20
8.
Ionisation energy is the energy required to remove one mole of electrons from one mole of its gaseous atoms
9.
Phosphorus has a higher ionisation energy than sulphur as sulphur has an electron paired in a sub orbital resulting in repulsion thus easier to remove.
10.
Magnesiums 2nd ionisation energy is a lot higher as nuclear charge is increased and sue to electron - electron repulsion
11.
Suggest a value for the IE - 1000???
12.
Lithium is ionised in mass spectrometer through an electron gun, The atom or molecule is ionised by knocking one or more electrons off to give a positive ion.
13.
Lithium RAM = 6.93
14.
Lithium7 and Lithium6 have the same chemical properties due to same electron number
15.
Lower m/z are deflected more thus Li6 is deflected more due to lower mass (one less neutron)
16.
Ef-Eb =deltaH
17.
Empirical formula for NO is N205
18.
0.32dm^3 volume of gas
19.
Atom economy 18.9/18.8/19%
20.
-36.6KJmol?
21.
Yield of NO Decreases as pressure increases, Thus Products have more moles
22.
Yield of NO Decreases as temperature increases, Exothermic reaction
23.
900C is used as although a lower temperature can result in more yield, higher temperature = faster rate of reaction
24.
Pipette to measure 25cm3 of solution
25.
Heat loss to surroundings result in experimental errors an thus different enthalpy values
26.
Zac could insulate the calorimeter
1.
Halftime - The time taken for the radioactivity of a specified isotope to fall to half its original value.
2.
Oxygen2- has 8 protons, 10 neutrons, 10 electrons
3.
226Ra decays into 222Rn
4.
Moles = 0.0111
5.
-417kJ/mol
6.
(gmol-1) gram per mole or, Mass of one mole of a compound
7.
x = 4 for the H20
8.
Ionisation energy is the energy required to remove one mole of electrons from one mole of its gaseous atoms
9.
Phosphorus has a higher ionisation energy than sulphur as sulphur has an electron paired in a sub orbital resulting in repulsion thus easier to remove.
10.
Magnesiums 2nd ionisation energy is a lot higher as nuclear charge is increased and sue to electron - electron repulsion
11.
Suggest a value for the IE - 1000???
12.
Lithium is ionised in mass spectrometer through an electron gun, The atom or molecule is ionised by knocking one or more electrons off to give a positive ion.
13.
Lithium RAM = 6.93
14.
Lithium7 and Lithium6 have the same chemical properties due to same electron number
15.
Lower m/z are deflected more thus Li6 is deflected more due to lower mass (one less neutron)
16.
Ef-Eb =deltaH
17.
Empirical formula for NO is N2050.
18.
32dm^3 volume of gas
19.
Atom economy 18.9/18.8/19%
20.
-36.6KJmol?
21.
Yield of NO Decreases as pressure increases, Thus Products have more moles
22.
Yield of NO Decreases as temperature increases, Exothermic reaction
23.
900C is used as although a lower temperature can result in more yield, higher temperature = faster rate of reaction
24.
Pipette to measure 25cm3 of solution
25.
Heat loss to surroundings result in experimental errors an thus different enthalpy values
26.
Zac could insulate the calorimeter
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