Which statement is true about shape?

A chemist adds 180.0 ml of a 1.77 mol/L of sodium thiosulfate solution to a reaction flask. Calculate the mass in grams of sodium thiosulfate the chemist has added to the flask. Be sure your answer has the correct number of significant digits.

Answer: 50.4 g

Explanation:

To calculate the number of moles for given molarity, we use the equation:

$\text{Moles of solute}={\text{Molarity of the solution}}\times{\text{Volume of solution (in L)}}$ .....(1)

Molarity of sodium thiosulfate solution = 1.77 M

Volume of sodium thiosulfate solution = 180.0 mL = 0.1800 L

Putting values in equation 1, we get:

$\text{Moles of sodium thiosulfate}={1.77}\times{0.1800}=0.319moles$

Mass of sodium thiosulfate = $moles\times {\text {Molar mass}}=0.319moles\times 158.11g/mol=50.4g$

Thus 50.4 g of sodium thiosulfate the chemist has added to the flask.

6 0

3 years ago

Find the cell potential for a system whose ∆G = +55 kJ and 3 moles of electrons are exchanged.

rosijanka [135]

Answer:- cell potential = -0.19 volts

Solution:- The equation that shows the connection between $\Delta G$ and cell potential, E is written as:

$\Delta G=-nFE$

in this equation, n stands for moles of electrons, E stands for cell potential and F stands for faraday constant and it's value is $\frac{96485C}{mol}$ .

It asks to calculate the value of E, so let's rearrange the equation:

$E=-\frac{\Delta G}{nF}$

Let's plug in the values in it:

$E=-\frac{55kJ}{3mol*96485C.mol^-}$

$E=-\frac{0.00019kJ}{C}$

since, $\frac{1kJ}{C}=1000V$

Where C stands for coulombs and V stands for volts.

So, $E=-\frac{0.00019kJ}{C}(\frac{1000V}{\frac{1kJ}{C}})$

E = -0.19 V

So, the cell potential is -0.19 volts.

4 0

3 years ago

What were the defects in Ruther Ford Atomic model?

juin [17]

the RutherFord atomic model has the limitations in explaining the stability of the atom and the stability of the electron.

<u>Explanation:</u>

As we know basically the atom comprises of the positively charged proton and negative charge electron and no charge neutron.
In these particles, electron revolves with the nucleus as a centre in the orbit with the different energy levels.
So by this revolving action, there will be the loss of energy and thus electrons are to be falling into the nucleus which affects the stability of the electron.
The atom is said to be neutral electrically if the protons and electrons are equal. So in the above case if the electrons on losing the energy if it fells into the nucleus, as a result, the stability of the atom is affected which makes the atom as ions.

7 0

3 years ago