Question

Problem Page A chemist adds of a calcium bromide solution to a reaction flask. Calculate the mass in grams of calcium bromide the chemist has added to the flask. Be sure your answer has the correct number of significant digits.

Answer 1

see explanation below

Step-by-step explanation:

First, you are not providing any data of the bromide solution to calculate the mass. So, in order to help you, I will take some random values from a similar exercise, so you can solve this later with your data.

Let's suppose you add 360 mL of a 1.45 mol/L of a calcium bromide solution into the flask. To calculate the mass it was added, you need to calculate first the moles added. This can be done with the following expression:

M = n/V

Where:

M: molarity of solution

n: moles of solution

V: volume (in liters) of solution

here, you have to solve for n, so:

n = M*V

replacing the above data you have:

n = 1.45 * (0.360) = 0.522 moles

Now that we have the moles, you can calculate the mass by the following expression:

m = n * MM

Where MM it's the molar mass of calcium bromide. The reported MM of calcium bromide is 199.89 g/mol, so replacing:

m = 199.89 * 0.522

m = 104.34 g

And this is the mass that was added of the solution. As I stated before, use your data in this procedure, and you should get an accurate result.