Answer:
[OH-] = 1.0 x 10-10 M
Explanation:
The acidity of a solution can be determined directly from the concentration of the hydrogen ions and indirectly from the concentrations of the hydroxide ions.
Generally, for a neutral solution we have;
[H3O+] = [OH-] = 1.0 x 10-7 M
For an acidic solution;
[H3O+] > 1.0 x 10-7 M
[OH-] < 1.0 x 10-7 M
Comparing the options the correct option is;
[OH-] = 1.0 x 10-10 M
Molar mass Na = 23.0 g/mol
1 mol ---- 23.0 g
n mol ---- 69 g
n = 69 / 23.0
n = 3.0 moles
1 mole -------- 6.02x10²³ molecules
3.0 moles ---- ?
3.0 * 6.02x10²³ / 1
= 1.806x10²⁴ molecules
hope this helps!
Coffee is acidic so the first one would be correct
