What would be the MOLARITY (M) of the NaBr in the same buffer solution, if its concentration is now 0.9% (w/v)?
Relative atomic masses:Na = 23; Br = 80
The same as what buffer solution.
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To determine the molarity (M) of NaBr in a 0.9% (w/v) solution, we first need to convert the mass of NaBr to grams and then calculate the number of moles.
Step 1: Convert the mass of NaBr from percent to grams
In a 0.9% (w/v) solution, 0.9 grams of NaBr are present in 100 mL of the solution.
Step 2: Calculate the number of moles of NaBr
To calculate the number of moles, we need to use the molar mass of NaBr, which is the sum of the atomic masses of sodium (Na) and bromine (Br).
Molar mass of NaBr = (atomic mass of Na) + (atomic mass of Br)
= (23 g/mol) + (80 g/mol)
= 103 g/mol
Now, we can calculate the number of moles of NaBr by dividing the mass of NaBr in grams by its molar mass.
Moles of NaBr = (mass of NaBr in grams) / (molar mass of NaBr)
= 0.9 g / 103 g/mol
Step 3: Convert the moles of NaBr to molarity (M)
Molarity is defined as the number of moles of solute divided by the volume of the solution in liters.
Molarity (M) = moles of NaBr / volume of solution (in liters)
Since we are not given the volume of the solution in the question, we cannot calculate the molarity without that information.
Therefore, to determine the molarity of NaBr in the solution, the volume of the solution is needed.