The Relative Formula Mass of NaH2PO4 is 120 g/mol
Therefore, the number of moles = 6.6/120
= 0.055 moles of NaH2PO4 which is also equal to the number of moles of H2PO4.
[H2PO4-] = Number of moles oof H2PO4-/Volume of the solution in L
= 0.055/ ( 355 ×10^-3)
= 0.155 M
Na2HPO4 undergoes complete dissociation as follows;
Na2HPO4 (aq)= 2Na+ (aq) + HPO4^2- (aq)
1 mole of Na2HPO4 = 142 g/mol
Therefore; number of moles = 8.0/142
= 0.0563 moles
[HPO4 ^-2] is given by no of moles HPO4^2- /volume of the solution in L
= 0.0563/(355×10^-3)
= 0.1586 M
Both H2PO4^2- and HPO4^2- are weak acids the undergoes partial dissociation
Ka of H2PO4- = 6.20 × 10^-8
[H+] =Ka*([H2PO4-]/[HPO4(2-)]
= (6.20 ×10^-8)×(0.155/0.1586)
= 6.059 ×10^-8 M
pH = - log[H+]
= - log (6.059×10^-8)
= 7.218
Answer:
0.234 M
Explanation:
C- 12.009 x 7
H- 1.001 x 5
N- 14.006
O- 16 x 3
S- 32.059
___________+
183.133 g/mol
= 0.234 M Cancel out the grams mol/L equals molarity. Lowest significant figure is 3
X is the chemical symbol of the element
B and c...will lose electron(s) in forming an Ion.
P is an Anion
b..Fe. and c...Pb form Cations (+) by losing electrons.
d. Se is an Anion.
Answer:
26
Explanation:
26 because if you split 56.23 in half you get 26