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An unknown amount of acid can often be determined by adding an excess of base and then back-titrating the excess. A 0.3471−g sam

MAXImum [283]

Explanation:

The given data is as follows.

Mass of mixture = 0.3471 g

As the mixture contains oxalic acid and benzoic acid. So, oxalic acid will have two protons and benzoic acid has one proton.

This means oxalic acid will react with 2 moles of NaOH and benzoic acid will react with 1 mole of NaOH.

Hence, moles of NaOH in 97 ml = $\frac{0.1090 \times 97}{1000}$

= $10.573 \times 10^{-3} mol$

Moles of HCl in 21.00 ml = $\frac{0.2060 \times 21}{1000}$

= $4.326 \times 10^{-3}$ mol

Therefore, total moles of NaOH that reacted are as follows.

$10.573 \times 10^{-3} mol$ - $4.326 \times 10^{-3} mol$

= $6.247 \times 10^{-3}$ mol

So, total 3 mole of NaOH will react with 1 mole of mixture. Therefore, number of moles of NaOH reacted with benzoic acid is as follows.

$\frac{6.247 \times 10^{-3}}{3}$

= $2.082 \times 10^{-3}$ mol

Since, molar mass of NaOH is 40 g/mol. Therefore, calculate the mass of NaOH as follows.

$2.082 \times 10^{-3} mol \times 40 g/mol$

= $83.293 \times 10^{-3}$ g

= 0.0832 g

Whereas molar mass of benzoic acid is 122 g/mol.

Therefore, 40 g NaOH = 122 g benzoic acid

So, 0.0832 g NaOH = $\frac{122 g}{40 g} \times 0.0832 g$

= 0.253 g

Hence, calculate the % mass of benzoic acid as follows.

$\frac{0.253 g}{0.3471 g} \times 100$

= 73.10%

Thus, we can conclude that mass % of benzoic acid is 73.10%.

4 0

3 years ago

Which of the following is true about an atom of silver

kati45 [8]

Answer:

where is options.

tell me

4 0

3 years ago

Read 2 more answers

What is the pOH value of 0.0000877 M HCL

ki77a [65]

Answer:

pOH=9.9

Explanation:

pH=-log[H+]= -log[0.0000877]

=4.06

pOH+ pH=14

pOH=14-4.06= 9.91

7 0

3 years ago

What does the t cell do to your body?

lawyer [7]

Answer: it's part of the immune system that focuses on specific foreign particles. Rather than generically attack any antigens, T cells circulate until they encounter their specific antigen. As such, T cells play a critical part in immunity to foreign substances !

Explanation:

4 0

3 years ago

Jennie observes her brother playing pool and has a theory that the potential energy in the pool stick is transformed into kineti

Shkiper50 [21]

A lot of theories exist in the world today regarding energy. The statement that explains how she can prove her theory is below:

He could measure the potential energy when the pool stick is pulled back before moving to strike the pool ball, and she could measure the kinetic energy of the ball in motion after the pool stick strikes it. There should be an equal amount of kinetic energy and potential energy to prove there was a transformation of potential energy to kinetic energy.

Potential energy is known to be of position relative, and kinetic energy is motion relative.

The relationship that exist between the two is their ability to transform into one another. That is potential energy transforms into kinetic energy, and kinetic energy converts into potential energy, and vice versa

If an outside force acts upon an object with potential energy, that force is said to change the potential energy into kinetic energy.

The full question is below

Jennie observes her brother playing pool and has a theory that the potential energy in the pool stick is transformed into kinetic energy when he hits the ball.

Which explains how she can prove her theory?

A

She could measure the potential energy in the motionless ball on the pool table, and she could measure the potential energy of the pool stick as it moves to strike the ball. These total of these two measurements will be equal to the kinetic energy in the pool ball as it moves, and this proves there was a transformation of energy.

B

She could measure the potential energy when the pool stick is pulled back to strike the pool ball, and then she could measure the kinetic energy in the pool stick as it moves to strike the ball. The potential energy in the pool stick and the kinetic energy in the pool stick should be equal, proving there was a transformation of energy.

C

She could measure the potential energy when the pool stick is pulled back before moving to strike the pool ball, and she could measure the kinetic energy of the ball in motion after the pool stick strikes it. There should be an equal amount of kinetic energy and potential energy to prove there was a transformation of potential energy to kinetic energy.

D

She could measure the potential energy of the pool ball when it was sitting on the table, and she could measure the kinetic energy of the ball in motion after the pool stick strikes it. There should be an equal amount of potential energy in the motionless ball and kinetic energy in the ball after the stick strikes it to prove there was a transformation of potential energy to kinetic energy.:

Learn more from

brainly.com/question/25841380

8 0

3 years ago