Reference no: EM13529625
One student used 0.1 mol/L NaOH to titrate an unknown diprotic acid. The concentration of the unknown acid is 5.1 g/L, and the volume of the unknown acid is 15ml.
I. the volume of NaOH is 12.2 nL at the second equivalent point
II. pH at half of the first equivalent point is 3.09
III. pKa2 is 4.31
a. Calculate Ka1 and Ka2 of the unknown acid
b. Calculate the equivalent weight of the unknown acid
c. compare the Ka1, Ka2 and the equivalent weight of the unknown acid with the date in the table below, the name of the unknown acid can be identifed as:
Acid Ka1 Ka2 Equivalent Weight
Oxalic acid 5.4x10-2 5.1x10-5 63
phthalic acid 1.3x10-3 3.1 x 10-6 83
malic acid 9.0x10-4 2.5x10-5 67
citric acid 7.4 x 10-4 5.0x10-5 64
|
Determine what is the final temperature of the mixture
: If 55.0 ml of ethanol (density=0.789 g/ml) initially at 8.0 C is mixed with 55.0 ml of water (density= 1.0 g/ml)ninitially at 28.6 C in an insulated beaker and assuming no heat is lost, what is the final temperature of the mixture
|
|
Find how much work does the towrope do on water-skier
: The tension in the horizontal towrope pulling a water-skier is 240 N, How much work does the towrope do on the water-skier
|
|
Explain the equilibrium constant for the reaction is keq
: PH for the reaction 2 H2O (l) H3O+(aq) + OH-(aq) is +55.8 KJ/mol. and the equilibrium constant for the reaction is Keq= 1.0x10-14. What is ?S for this reaction
|
|
Calculate the angular speed of rotation
: In an amusement park ride, cars are suspended from L = 4.29 m cables attached to rotating arms at a distance of D = 6.11 m from the axis of rotation. What is the angular speed of rotation
|
|
Explain naoh to titrate an unknown diprotic acid
: One student used 0.1 mol/L NaOH to titrate an unknown diprotic acid. The concentration of the unknown acid is 5.1 g/L, and the volume of the unknown acid is 15ml.
|
|
Explain hcl solution to an unknown solution of metal ions
: On adding 10 drops of 6M HCl solution to an unknown solution of metal ions, a CHem-127 student observed a white precipitate being formed. the white precipitate may contain
|
|
Find how fast is your car moving in kilometers per hour
: Your car's wheels are 65 cm in diameter and the wheels are spinning at an angular velocity of 107 rad/s. How fast is your car moving in kilometers per hour
|
|
The empirical formula if a compund containing nickel
: A student find out the mass percent of Ni is 29.7%, NH3 is 34.4%, and Cl is 35.9% in a compund containing Nickel, ammonia, and chlorine. The empirical formula of the compund is
|
|
Determine her initial velocity
: A diver springs upward from a diving board. At the instant she contacts the water, her speed is 8.90 m/s, and her body is extended at 75.0 degrees with respect to the horizontal surface of the water. Determine her initial velocity
|