Question

PH experiment:

What is one real-world or practical application for this experiment or portion of this experiment?

Define the following: abscissa, acid, base, endpoint, equivalence point, neutralization, pH, pKa, mono- protic acid, polyprotic acid, ordinate, strong acid, strong base, and weak acid.

Draw the structure of each of the acids in Table 1.

Produce data tables for each of your runs. Leave room in your notebook for lots of data. Record the actual volume of titrant and solution pH as you conduct the experiment.

Identify all potentially hazardous steps in your procedure. In your own words, explain what safety precautions should be taken and why.

Consider the titration of 0.050 M HCl with 0.050 M NaOH. Calculate the pH: (a) of the pure HCl solution; (b) of 25.00 mL acid plus 12.50 mL base; (c) at the equivalence point; and (d) of 25.00 mL acid and 37.50 mL base.

Consider the titration of 0.050 M NaOH with 0.050 M HCl. Calculate the pH: (a) of the pure NaOH solution; (b) of 25.00 mL base plus 12.50 mL acid; (c) at the equivalence point; and (d) of 25.00 mL base and 37.50 mL acid.

In one experiment, an unknown acid was titrated with NaOH. The pH at the equivalence point was 7.75. Was the unknown acid strong or weak? Explain. Hint: The pH of pure water at room temperature is 7.

Answer 1

Answer: PH experiment will be used to identify the acids and bases depending on thiere PH value.

• abscissa is the perpendicular distance of a point from the vertical axis
• Those who donate protons in soltion are acids, which are sour in taste.Further acid turns blue litmus paper into red.
• Those who donate hydroxy ions in soltion are bases, which are bitter in taste.Further acid turns red litmus paper into blue.
• In a titration, end point where colour change will be observed suddenly while titrating. End point also can be called euilance point.
• Neutralization is a point where PH of solution is 7
• PH: The acidity or alkalinity of a solution on a logarithmic scale on which 7 is neutral, lower values are more acid and higher values more alkaline. The pH is equal to −log₁₀c, where c is the hydrogen ion concentration in moles per litre
• PKa: pKa was introduced as an index to express the acidity of weak acids, where pKais defined as follows. For example, the Ka constant for acetic acid (CH₃C00H) is 0.0000158 (= 10^-4.8), but the pKa constant is 4.8, which is a simpler expression. In addition, the smaller the pKa value, the stronger the acid.
• Molecule who is capable of produce one proton in solution is called monoprotic acid.
• Molecule who is capable of produce more protons in solution is called polyprotic acid.
• Ordinate: ordinate most often refers to that element of an ordered pair which is plotted on the vertical axis of a two-dimensional Cartesian coordinate system, as opposed to the abscissa
• Strong acid is able to produce protons easily in and Strong base is able to produce hydroxy ions easily in solution.
• PH of 0.05M solution HCl is 1.3
• At equalent point PH = 7
• PH of 25 mL of 0.05M HCl and 21.5 mL of 0.05M NaOH = 1.77
• PH of 25 mL 0.05M HCl and 37.5 mL of 0.05M NaOH = 12.8
• PH of 0.05 NaOH solution = 12.7
• When we do acid base titration, for strong acid and base at equalant point PH almost around 7, therefore, in titration acid must be strong.