To determine the mass percentage of the solution for the customer in the hospital, molarity for the customer in the chemistry lab, and molality for the customer of the physics lab, we need to calculate the mass of NaCl, molarity, and molality.
1. Mass percentage of the solution for the customer in the hospital:
To calculate the mass percentage, we need to find the mass of NaCl in the solution and divide it by the total mass of the solution, then multiply by 100.
Mass of NaCl = 900 kg
Total mass of the solution = 100 liters (assumed to be equal to 100 kg because 1 liter of water has a mass of 1 kg)
Mass percentage = (mass of NaCl / total mass of the solution) x 100
= (900 kg / 100 kg) x 100
= 900%
The mass percentage of the solution for the customer in the hospital is 900%.
2. Molarity for the customer in the chemistry lab:
Molarity is defined as the number of moles of solute (NaCl) per liter of solution. To calculate the molarity, we need to find the number of moles of NaCl and divide it by the volume of the solution in liters.
Number of moles of NaCl can be calculated using the formula:
moles = mass / molar mass
Mass of NaCl = 900 kg
Molar mass of NaCl = molar mass of Na (22.99 g/mol) + molar mass of Cl (35.45 g/mol) = 58.44 g/mol
Converting the mass of NaCl from kg to g:
Mass of NaCl = 900 kg x 1000 g/kg = 900,000 g
Number of moles of NaCl = 900,000 g / 58.44 g/mol = 15,401.2 mol
Now, let's calculate the molarity:
Molarity = moles of NaCl / volume of the solution (in liters)
= 15,401.2 mol / 100 liters
= 154.012 mol/L
The molarity for the customer in the chemistry lab is 154.012 mol/L.
3. Molality for the customer of the physics lab:
Molality is defined as the number of moles of solute (NaCl) per kilogram of solvent (water). To calculate the molality, we need to find the number of moles of NaCl and divide it by the mass of water in kilograms.
Number of moles of NaCl remains the same as calculated previously:
Number of moles of NaCl = 15,401.2 mol
Mass of water = 100 liters (assumed to be equal to 100 kg as mentioned earlier)
Now, let's calculate the molality:
Molality = moles of NaCl / mass of water (in kg)
= 15,401.2 mol / 100 kg
= 154.012 mol/kg
The molality for the customer of the physics lab is 154.012 mol/kg.
In summary:
- The mass percentage of the solution for the customer in the hospital is 900%.
- The molarity for the customer in the chemistry lab is 154.012 mol/L.
- The molality for the customer of the physics lab is 154.012 mol/kg.