The answer is B hope it helped
To determine the molar mass, you need to get the atomic mass of the molecule. To do this, check the periodic table for the atomic mass or average atomic weight of each element.
Mg = 24.305 x 1 = 24.305 amu
O = 15.9994 x 2 =31.9988 amu
H = 1.0079 x 2 = 2.0158 amu
Then, add all the components to get the atomic mass of the molecule.
24.305 amu + 31.9988 amu + 2.0158 amu = 58.3196 amu
The atomic mass is just equivalent to its molar mass.
So, the molar mass of Magnesium hydroxide (Mg(OH)2) is 58.3196 g/mol.
Answer:
The volume of a sample of gas (2.49 g) was 752 mL at 1.98 atm and 62∘C 62 ∘ C .
When the Pka for formic acid = 3.77
and Pka = -㏒ Ka
3.77 = -㏒ Ka
∴Ka = 1.7x10^-4
when Ka = [H+][HCOO-}/[HCOOH]
when we have Ka = 1.7x10^-4 &[HCOOH] = 0.21 m
so by substitution: by using ICE table value
1.7x10^-4 = X*X / (0.21-X)
(1.7x10^-4)*(0.21-X) = X^2 by solving this equation for X
∴X = 0.0059
∴[H+] = 0.0059
∴PH= -㏒ [H+]
= -㏒ 0.0059
= 2.23
