Answer
1.25M
Explanation
to calculate the molality we use the following equation
Molality = moles of solute / Kg of solvent
step 1: to find the moles of glucose we divide the mass by the Molar mass of glucose
moles = mass (g)/ Molar mass (g/mol)
= 18.0 g / 180,156 g/mol
= 0.0999 moles of glucose
now that we have moles of glucose, the next step is to convert 80.0g of water to Kg of water
1 kg = 1000g
Kg of water = 80g/1000g /kg
= 0.08Kg
Molality = 0.0999 mols / 0.08 kg
= 1.25M
