Physical Chemistry Flashcards
What is an isotope
Same amount of protons different amount of neutrons
What is mass number ?
Total Amount of protons and neutrons
State why isotopes of an element have the same chemical properties.
Same electron configuration
How are ions formed in the mass spectrometer
Sample dissolved in a volatile solution and injected through a hyper dermic needle giving a fine mist/vapour. Needle has a high voltage.
Loses electron to form ion.
How is relative abundance of an ion measured in a mass spectrometer
Abundance is proportional to the size of the current produced when it hits the plate
What block contains rubidium
S block
Where is relative abundance determined
The detector
State and explain the general trend in values for the first ionisation energies of the elements Na- Ar
Ionisation increases
Because outer electrons are closer to the nucleus so more attraction.
What is meant by First Ionisation Energy
Amount of energy needed to removed 1 electron from each atom in 1 mole of gaseous atoms to form 1 mole of gaseous 1+ ions.
Write full electron configuration of Al2+ ion
(- 2 electrons )
1s2 2s2 2p6 3s1
Complete the electron configuration for the sodium ion ,
Na+
(-1 electron )
1s2 2s2 2p6
State and explain the trend in atomic radius of the period 3 elements sodium to chlorine
Decreases
Increasing nuclear charge
Electrons have similar sheilding
Explain why the ionisation energy of every element is endothermic
Heat is needed to overcome bonds from negative electron and positive proton/nucleas
Work out abundance
M/z = 90 RA = 9
M/z= 91 RA = 2
M/z = 91 RA= 3
M/z= 94. RA=3
(90x9) + (91x2)+(92x3)+(94x3)
Divided by 17=
91.2
This element is Zincronium
