A solution of sulfuric acid in water that is 25% H2SO4 by mass has a density of 1178 g/ml. Which expression gives the molarity of this solution?
Surely the density is not that high. You didn't give any expressions for the molarity.
To determine the molarity of a solution, we need to know the number of moles of solute (sulfuric acid) dissolved in a given volume of solvent (water).
First, let's understand the given information:
- The solution is 25% H2SO4 by mass, which means that 25g of sulfuric acid is present in every 100g of the solution.
- The density of the solution is given as 1178 g/ml, which means that 1 ml of the solution has a mass of 1178g.
To calculate the molarity, we need to convert the mass of sulfuric acid to moles and the volume of the solution to liters. Then we can use the formula:
Molarity (M) = moles of solute / volume of solution (in liters)
Let's calculate the moles of sulfuric acid:
Moles of solute = Mass of sulfuric acid / molar mass of sulfuric acid
The molar mass of H2SO4 is calculated as follows:
2 atoms of hydrogen (2.02 g/mol) + 1 atom of sulfur (32.07 g/mol) + 4 atoms of oxygen (16.00 g/mol) = 98.09 g/mol
Now, let's plug in the values and calculate:
Moles of solute = (25g / 100g) / 98.09 g/mol
Next, we need to convert the volume of the solution to liters:
Volume of solution = mass of solution / density of solution
Since the density is given as 1178 g/ml and 1 ml = 1 cm^3, we can rewrite the equation as:
Volume of solution = mass of solution / density of solution = 1 ml / 1178 g
Finally, we can calculate the molarity:
Molarity (M) = (moles of solute) / (volume of solution in liters)
Therefore, the expression that gives the molarity of the sulfuric acid solution is:
Molarity (M) = ((25g / 100g) / 98.09 g/mol) / (1 ml / 1178 g)