Write up titration
11053457
Iman B.Zamani
Titration of NaOH with potassium hydrogen phthalate to determine
the molarity of NaOH
Introduction, Titration is a common lab procedure, which gives highly accurate
results if done properly, for a variety of chemicals. Titrations are often used to
determine the concentration of a solution like an acid or a base. This uses of a
known reaction between two chemicals, for this we need a solution, with an
unknown concentration, this will be reacted with a precisely measured of another
chemical wich we known the molar mass of it.
And an indicator is used, to show when the same amount of each chemicals are
combined, wich we will see in the balance equation, the exact molar ratio of the
reaction. This is called equivalence point. To maesure this accurately the volumes of
solutions, buretes must be finely calibrated.
In this experiment, we determined the exact molar concentration of sodium
hydroxide, which we prepared in class. Even if we aldready knew that there was 5g
the actuall concentration will be different due to chemical interaction of the hydroxide
ion with other disolved substances in water particulary CO 2. If we assuMe that the
molarity is 5g would lead to inaccuracies in subsequent titrations where the
concentration of the NaOH solution must be known with great accuracy. The process
of earning the exact concentration of the NaOH solution is commonly called
standardizing.
Something that we followed and it is important to mention, is safety, goggles must be
where'd when working with acid or base solutions, and the glasswear must be clean,
and also use deionized water for all rinsing and mixing.
Preparing the buret
1, The buret was already set up for us in this practical, but it is pretty easy to do just
secure a buret for base in a clamp, and making sure that the valve is closed, wich we
noticed when the tap was in a cross set up +, if the tap is vertical mean that it is
open, also making sure that the tip doesent hit any other objects.
2, To make sure that the burete was clean, we rinse it with deionized water, or
rubbing soap with a brush and rainsing with distilled water, If water runs smoothly
along the inside of the buret, you know that the glass is clean that was already been
done by the technician, after this the buret is ready to recive the solution to be titrted.
Also while rainsing it a second time it is a good thing because we can see if the
water is draining out properly, andpracticing the control of rate of fluid delivery. See if
he buret is able to deliver liquid one drop at a time. Also studying the volume
markings on the buret and trying to read the level of the meniscus to the nearest
0.01 ml, this should always be at eye level.
11053457
Iman B.Zamani
Titration of NaOH with potassium hydrogen phthalate to determine
the molarity of NaOH
Introduction, Titration is a common lab procedure, which gives highly accurate
results if done properly, for a variety of chemicals. Titrations are often used to
determine the concentration of a solution like an acid or a base. This uses of a
known reaction between two chemicals, for this we need a solution, with an
unknown concentration, this will be reacted with a precisely measured of another
chemical wich we known the molar mass of it.
And an indicator is used, to show when the same amount of each chemicals are
combined, wich we will see in the balance equation, the exact molar ratio of the
reaction. This is called equivalence point. To maesure this accurately the volumes of
solutions, buretes must be finely calibrated.
In this experiment, we determined the exact molar concentration of sodium
hydroxide, which we prepared in class. Even if we aldready knew that there was 5g
the actuall concentration will be different due to chemical interaction of the hydroxide
ion with other disolved substances in water particulary CO 2. If we assuMe that the
molarity is 5g would lead to inaccuracies in subsequent titrations where the
concentration of the NaOH solution must be known with great accuracy. The process
of earning the exact concentration of the NaOH solution is commonly called
standardizing.
Something that we followed and it is important to mention, is safety, goggles must be
where'd when working with acid or base solutions, and the glasswear must be clean,
and also use deionized water for all rinsing and mixing.
Preparing the buret
1, The buret was already set up for us in this practical, but it is pretty easy to do just
secure a buret for base in a clamp, and making sure that the valve is closed, wich we
noticed when the tap was in a cross set up +, if the tap is vertical mean that it is
open, also making sure that the tip doesent hit any other objects.
2, To make sure that the burete was clean, we rinse it with deionized water, or
rubbing soap with a brush and rainsing with distilled water, If water runs smoothly
along the inside of the buret, you know that the glass is clean that was already been
done by the technician, after this the buret is ready to recive the solution to be titrted.
Also while rainsing it a second time it is a good thing because we can see if the
water is draining out properly, andpracticing the control of rate of fluid delivery. See if
he buret is able to deliver liquid one drop at a time. Also studying the volume
markings on the buret and trying to read the level of the meniscus to the nearest
0.01 ml, this should always be at eye level.
