After standardizing a NaOH solution, you use it to titrate an HCl solution known to have a concentration of 0.205 M. You perform five titrations and obtain the following results: 0.213, 0.204, 0.208, 0.200, and 0.198 M.
a) What is the mean?
b) What is the standard deviation of mean?

Respuesta :

Answer:

The right answer is:

(a) 0.205

(b) 0.005425

Step-by-step explanation:

The given data is:

0.213, 0.204, 0.208, 0.200, and 0.198

(a)

The mean will be:

= [tex]\frac{Sum \ of \ all \ data}{No. \ of \ data}[/tex]

= [tex]\frac{0.213+ 0.204+ 0.208+ 0.200+0.198}{5}[/tex]

= [tex]\frac{1.023}{5}[/tex]

= [tex]0.2046[/tex]

or,

= [tex]0.205[/tex]

(b)

The standard deviation will be:

[tex]\sigma^2=\Sigma\frac{(x_i-\mu)^2}{N}[/tex]

    [tex]=\frac{(0.213-0.2046)^2+...+(0.198-0.2046)^2}{5}[/tex]

    [tex]=\frac{0.0001472}{5}[/tex]

    [tex]=2.994\times 10^{-5}[/tex]

or,

    [tex]=0.005425[/tex]