Tare the balance. Put calorimeter (no lid) on the balance.

The pKs of succinic acid are 4.21 and 5.64. How many grams of monosodium succinate (FW = 140 g/mol) and disodium succinate (FW =

Varvara68 [4.7K]

Answer:

9.744g of monosodium succinate.

4.925g of disodium succinate.

Explanation:

To find pH of the buffer produced by the mixture of monosodium succinate-Disodium succinate is obtained from H-H equation:

pH = pKa + log ([Na₂Suc] / [NaHSuc])

As you want a pH of 5.28 and pKa is 5.64:

5.28 = 5.64 + log ([Na₂Suc] / [NaHSuc])

-0.36 = log ([Na₂Suc] / [NaHSuc])

0.4365 = ([Na₂Suc] / [NaHSuc]) (1)

As total concentration of the buffer is 100mM = 0.100M:

0.100M = [Na₂Suc] + [NaHSuc] (2)

Replacing (2) in (1):

0.4365 = (0.100M - [NaHSuc] / [NaHSuc])

0.4365 [NaHSuc] = 0.100M - [NaHSuc]

1.4365 [NaHSuc] = 0.100M

[NaHSuc] = 0.0696M

And:

[Na₂Suc] = 0.0304M

As volume of the buffer is 1L:

[NaHSuc] = 0.0696 moles

[Na₂Suc] = 0.0304 moles

Using molar mass of both substances:

Mass of monosodium succinate:

0.0696moles * (140g / 1mol) = 9.744g of monosodium succinate.

Mass of disodium succinate:

0.0304moles * (162g / 1mol) = 4.925g of disodium succinate.

5 0

2 years ago

When a pan containing liquid and solid water (ice water) is put over the flame of a stove and stirred vigorously 1. the temperat

nata0808 [166]

When a pan containing liquid and solid water (ice water) is put over the flame of a stove and stirred vigorously: 2. the temperature rises but only after the ice melts.
It is known that ice lower the temperature of solution, after ice is melt temperature of liquid start to rise normally. Temperature of ice is 0°C.

3 0

2 years ago

Consider the following oxides: SO2, Y2O3, MgO, Cl2O, and N2O5. How many are expected to form acidic solutions in water? Consider

Snowcat [4.5K]

Answer:

Three of the five oxides are expected to form acidic solutions in water

Explanation:

We have different types of oxides : Acidic oxides, Basic oxides, Amphoteric oxides, Peroxides and Higher oxides.

Only acidic oxides will dissolve in water to give an acidic solution.

Considering the given oxides carefully,

SO2 will dissolve in water to produce H2SO3 which is acidic.

Y2O3 will dissolve in water to produce Yttrium(III) hydroxide which is basic.

MgO will dissolve in water only to produce Mg(OH)2 which is also basic.

Cl2O dichlorine mono oxide will dissolve in water to produce HClO which is acidic.

N2O5 will dissolve in water to produce HNO3 which is also acidic.

5 0

2 years ago

Which solution contains the largest number of moles of chloride ions?

elixir [45]

Molarity = number of moles of solute/liters of solution
number of moles of solute = molarity x liters of solution

Part (a): 30.00 ml of 0.100m Cacl2
number of moles of CaCl2 = 0.1 x 0.03 = 3x10^-3 moles
1 mole of CaCl2 contains 2 moles of chlorine, therefore 3x10^-3 moles of CaCl2 contains 6x10^-3 moles of chlorine

Part (b): 10.0 ml of 0.500m bacl2
number of moles of BaCl2 = 0.5 x 0.01 = 5x10^-3 moles
1 mole of BaCl2 contains 2 moles of chlorine, therefore 5x10^-3 moles of BaCl2 contains 10x10^-3 moles of chlorine

Part (c): 4.00 ml of 1.000m nacl
number of moles of NaCl = 1 x 0.004 = 0.004 moles
1 mole of NaCl contains 1 mole of chlorine, therefore 4x10^-3 moles of NaCl contains 4x10^-3 moles of chlorine

Part (d): 7.50 ml of 0.500m fecl3
number of moles of FeCl3 = 0.5 x 0.0075 = 3.75x10^-3 moles
1 mole of FeCl3 contains 3 moles of chlorine, therefore 3.75x10^-3 moles of FeCl3 contains 0.01125 moles of chlorine

Based on the above calculations, the correct answer is (d)

5 0

2 years ago

Read 2 more answers

Sixty-five percent of the mass of bone is a compound called hydroxyapatite. sixty-five percent of the mass of bone is a compound

mafiozo [28]

True. Its simple how i remeberd was the bone has 650,000 cells and the bone has 65% hydroxyapatite

5 0

2 years ago