HELP!!!!!!A solution made from 19.0 g of Na Br and 500 ml of water has what molarity?
0.038
moles NaBr = grams/molar mass
M = moles/L soln.
Note: There is no space between Na and Br.
To find the molarity of the solution, we need to know the number of moles of sodium bromide (NaBr) and the volume of the solution in liters.
Step 1: Convert the mass of NaBr to moles.
To find the number of moles, we divide the mass of NaBr by its molar mass. The molar mass of NaBr 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)
= (22.99 g/mol) + (79.90 g/mol)
= 102.89 g/mol
Number of moles = mass / molar mass
= 19.0 g / 102.89 g/mol
≈ 0.1847 mol
Step 2: Convert the volume of water to liters.
The volume of water is given as 500 ml. To convert it to liters, divide the volume by 1000.
Volume in liters = 500 ml / 1000 ml/L
= 0.5 L
Step 3: Calculate the molarity.
Molarity (M) is defined as moles of solute per liter of solution.
Molarity = moles / volume
= 0.1847 mol / 0.5 L
= 0.3694 M
Therefore, the molarity of the solution made from 19.0 g of NaBr and 500 ml of water is approximately 0.3694 M.