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2 years ago

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Chemistry

1 answer:

kow [346]2 years ago

8 0

Answer:

please what do you mean

Explanation:

explain please

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Calculate the pH of a solution prepared by dissolving 0.370 mol of formic acid (HCO2H) and 0.230 mol of sodium formate (NaCO2H)

Veronika [31]

The question is incomplete, here is the complete question:

Calculate the pH of a solution prepared by dissolving 0.370 mol of formic acid (HCO₂H) and 0.230 mol of sodium formate (NaCO₂H) in water sufficient to yield 1.00 L of solution. The Ka of formic acid is 1.77 × 10⁻⁴

a) 2.099

b) 10.463

c) 3.546

d) 2.307

e) 3.952

<u>Answer:</u> The pH of the solution is 3.546

<u>Explanation:</u>

We are given:

Moles of formic acid = 0.370 moles

Moles of sodium formate = 0.230 moles

Volume of solution = 1 L

To calculate the molarity of solution, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}$

To calculate the pH of acidic buffer, we use the equation given by Henderson Hasselbalch:

$pH=pK_a+\log(\frac{[salt]}{[acid]})$

$pH=pK_a+\log(\frac{[HCOONa]}{[HCOOH]})$

$pK_a$ = negative logarithm of acid dissociation constant of formic acid = 3.75

$[HCOONa]=\frac{0.230}{1}$

$[HCOOH]=\frac{0.370}{1}$

pH = ?

Putting values in above equation, we get:

$pH=3.75+\log(\frac{0.23/1}{0.37/1})\\\\pH=3.54$

Hence, the pH of the solution is 3.546

5 0

3 years ago

The difference between diffusion and osmosis is that osmosis deals only with ________.

Nat2105 [25]

Osmosis deals only with D. Water. Diffusion and Osmosis are relatively the same thing besides the fact that water is largely incorporated with the osmosis.

6 0

3 years ago

Moon rocks collected on the moon were returned to earth are made of basalt, a light volcanie rock, have a density of 2.7 g/cm?.

Marina86 [1]

Answer:

160cm³

Explanation:

$V = \frac{m}{D} = \frac{432}{2.7} = 160$

5 0

3 years ago

A student dissolves 3.9g of aniline (C6H5NH2) in 200.mL of a solvent with a density of 1.05 g/mL . The student notices that the

Tresset [83]

Answer:

a. Molarity= $M =2.1x10^{-1}M$

b. Molality= $m=2.0x10^{-1}m$

Explanation:

Hello,

In this case, given the information about the aniline, whose molar mass is 93g/mol, one could assume the volume of the solution is just 200 mL (0.200 L) as no volume change is observed when mixing, therefore, the molarity results:

$M=\frac{n_{solute}}{V_{solution}} =\frac{3.9g*\frac{1mol}{93g} }{0.2L} =2.1x10^{-1}M$