The procedure, which can be used to determine more accurately the concentration of the unknown acid is TO BACK-TITRATE WITH ADDITIONAL HYDROCHLORIC ACID TO NEUTRALIZE THE ADDITIONAL SODIUM HYDROXIDE THAT WAS ADDED.
Monoprotic acids are acids that can donate only one proton per each molecule and they have only one equivalence point. Examples of monoprotic acids are HCI, HNO3 and CH3COOH.
The back titration method is typically used when one needs to determine the concentration of an analyte provided there is a known molar concentration of excess reactants.
From the information given in the question above, we are told that excess NaOH was added. To correct this mistake, the right thing to do is to use additional HCl to carry out back titration, taking note of the quantity of acid that will be needed to neutralize the excess NaOH.
Solution contains 45% salt
She wants to obtain 180 ounces of a mixture that
is 30% salt
Ounces of water with 45% salt solution = ?
30% = 0.3 and 45% = 0.45
Let V is the volume of water to be mixed in
ounces, then the volume of the 45% salt solution needed is 180-V
The balanced equation for the mass of salt is
0.45 x (180-V) = 0.3 x 180
81 – 0.45V = 54
0.45V = 81-54
0.45V = 27
V = 60
<span>So, 60 ounces of water is needed</span>
There is only one product in a synthesis reaction.
I think thee correct answer from the choices listed above is option D. <span>When a physical change in a sample occurs, composition of the sample does not change. It stays the same. Also, the properties of the sample will still be the same. Hope this answers the question.</span>