Answer:
a )Li
b)O
c)F
Explanation:
a) Li-1s^2 2s^1
F-1s^2 2s^2 2p^5
it is easy to pull out e- from 2p orbit than 2s because 2s orbit is close to nucleus.Therefore Li have high ionisation enthalpy
b)oxygen ion is larger than Na because o have fewer proton
c)F because it requires only 1e to achieve stable noble gas configuration.Therefore to achieve stable nobke gas electonic configuration it accept 1e.
First let us calculate for the molar mass of ibuprofen:
Molar mass = 13 * 12 g/mol + 18 * 1 g/mol + 2 * 16 g/mol
Molar mass = 206 g/mol = 206 mg / mmol
Calculating for the number of moles:
moles = 200 mg / (206 mg / mmol)
moles = 0.971 mmol = 9.71 x 10^-4 moles
Using the Avogadros number, we calculate the number of
molecules of ibuprofen:
Molecules = 9.71 x 10^-4 moles * (6.022 x 10^23 molecules
/ moles)
<span>Molecules = 5.85 x 10^20 molecules</span>
Answer:
Because scientists call vaccines reagents.