<u>Answer:</u>
0.058 M
<u>Explanation:</u>
HBr reacts with NaOH and forms NaBr and H₂O as the products. The balanced equation is as follows:

Molarity (M) = moles of solute (mol) / volume of the solution (L)
Molarity of NaOH = 0.115 M
Volume of NaOH = 18.2 mL = 18.2 x 10⁻³ L
So, moles of NaOH = molarity x volume of the solution
= 0.115 M x 18.2 x 10⁻³ L
= 2.093 x 10⁻³ mol
From the equation, we can see that the ratio between NaOH and HBr is 1 : 1.
Therefore, moles of HBr in 35.6 mL = moles of NaOH added = 2.093 x 10⁻³ mol
Hence, molarity of HBr = 2.093 x 10⁻³ mol
/ 35.6 x 10⁻³ L = 0.058 M
I honestly don’t know the answer to this one
Answer:125ml - volume of phosphoic acid
Explanation:
The equation of the reaction is
H3PO4 + 3 NaOH ---> Na3PO4 + 3H2O
Such that I mole of H3PO4 reacts with 3 moles of NaOH to produce the products above.
Given that
M1= Molarity of phosphoric acid = 7.48x10^-2 M
n1= number of moles of phosphoric acid = 1
V1=? ml
M2= Molarity of Sodium hydroxide =0.244 M
V2= volume of sodium hydroxide= 115ml
n2=number of moles of sodium hydroxide = 3
Using the Dilution equation formulae,
M1V1/n1 = M2V2/n2
7.48X10-2 x V1 /1= 0.244M x 115ml/3
V1=0.244Mx115mlx1/0.0748M X 3
V1= 28.06/0.2244= 125.04ml
V1=125.04ml rounded up to 125ml