if I have 3 tablespoons of sugar (15 grams) and dissolve it in 1 cup (~237 mL) and take out 30 mL what is the molarity in the 30 mL?
M=15/molmass /.237
molmass sucrose=342g/mole
M=15/(342*.237)=.185
To find the molarity in the 30 mL of solution, we need to know the number of moles of sugar present in that volume. Molarity (M) is defined as the number of moles of solute divided by the volume of the solution in liters.
First, convert the given mass of sugar (15 grams) to moles. The molar mass of sugar (C12H22O11) is 342.3 g/mol. Thus, the number of moles (n) can be calculated using the formula:
n = mass / molar mass
= 15 g / 342.3 g/mol
Next, convert the given volume of the solution (30 mL) to liters by dividing it by 1000:
Volume (in liters) = 30 mL / 1000
= 0.03 L
Now, we have the number of moles of sugar and the volume of the solution in liters. Calculate the molarity (M) using the formula:
M = n / V
where n is the number of moles and V is the volume of the solution in liters.
M = (15 g / 342.3 g/mol) / 0.03 L
By performing the calculation, you will get the molarity of the solution in the 30 mL volume.