Answer:
Rb > K > Na > Li
Explanation:
Ionization energy increases up the period and up the group.
From the periodic table, we can see that Li is the going to have the highest ionization energy and Rb is going to have the lowest.
Therefore, the correct answer is the first choice
Answer:
860 J / mol
Explanation:
Enthalpy = Energy / no. of moles
no. of moles = mass / molar mass
Take the atomic mass of H = 1.0,
molar mass of H2 = 1.0 x 2
= 2.0
no. of moles of H2 = 9.00/2
= 4.5 mol
Hence,
Enthalpy = 3870 / 4.5
=860 J / mol
Group 1: +1
Group 2: +2
Group 13: +3
Group 14: +4
Group 15: -3
Group 16: +II
Group 17: -1
The reaction equation:
2Li + O → Li₂O
Molar ratio of Li to Li₂O is:
2 : 1
So if 3.03 moles of Li are present:
2/1 = 3.03 / x
x = 1.515 moles of Li₂O will be produced.
