Unknown Acid Molarity

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Introduction:

The unknown acid molarity will be determining by titration method. Titration is a process depends on concentration of known solution to another solution until the solute in the another solution completely react. Standard solution is the solution of known concentration that used in titration. In this experiment, NaOH was the titrant (base) however, the two analyte which used were HCl and H2SO4.

The chemical reaction equations are molecular and ionic molecular equation for (NaOH) and (HCL) is:
HCl (aq) + NaOH (aq) --> H2O (l) + NaCl (aq)
The Net Ionic equation is:
H+ (aq) + OH- (aq) --> H2O (l)
Molecular equation for (NaOH) and (H2SO4) is:
H2SO4(aq) +2NaOH(aq) --> Na2SO4+ 2H2O
The Net Ionic equation is:
H+ (aq) + OH- (aq) -->
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It is highly reactive and it is solutions are not considered to be carcinogens, the molar mass for H2SO4 is 98.09 g/mol. However, hydrochloric acid is corrosive and it is colorless, with the molecular formula HCL. The molar mass for HCl is 36.46 g/mol. Phenolphthalein is flammable and harmful; it is absorbed through the skin. To be safe avoid contact with eyes, skin, and clothing. In case of skin contact, eye contact, ingestion or inhalation, lab coats, gloves and safety spectacles were worn at all times throughout the experiment. In this experiment the alkali NaoH(aq) has been collected about 100 cm3 in a large beaker and about 75 cm3 were collected for the acid in a small…show more content…
Step 4:

Calculate the molarity of the analyte HCl(aq)

M(HCl) = n/V = 2.235x10^-3 / 0.0250 = 0.0894 M

Finding with H2SO4:

Find the Molarity of H2SO4(aq) with analyte NaOH(aq).

Step 1:

Alkali NaOH(aq) (ANALYTE) Acid H2SO4 (aq) (TITRANT)

V(NaOH) = 31.50 cm3 - 0.0315 dm3 V(H2SO4) = 25 cm3 - 0.0250 dm3
M(NaOH) = 0.100 M M(H2SO4) =?

Step 2:

M = n/V, n(NaOH) = M x V = 0.100 x 0.0315 = 3.15x10^-3

Step 3:

The chemical equation: H2SO4(aq) +2NaOH(aq) --> Na2SO4+ 2H2O
1mol 2mole Molar ratio = H2SO4:NaOH = 1:2 = ? : 3.15x10^-3
Thus, n(H2SO4)= 3.15x10^-3 /2 = 1.1175 x10^-3 mol
This mean that 1.1175x10^-3 mole of H2SO4(aq) is used in this experiment.

Step 4:

Calculate the molarity of the analyte HCl(aq)

M(H2SO4) = n/V = 1.1175 x10^-3 / 0.0250 = 0.0447

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