Question

A chemist adds of a 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 1

This is a incomplete question.The complete question is:

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

Step-by-step explanation:

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

`\text{Moles of solute}={\text{Molarity of the solution}}*{\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}*{0.1800}=0.319moles`

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

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