I need to calcuted the molarity from this
12.5 g of ethylene glycol antifreeze dissolved in o.100kg of water. Density of solution is 1.0 g/mL
I know molarity if mole of solute / L of solution.
I am confused on how to find the L of solution. Do I add 12.5 and .100g to get the solution mass. Since 12.5 is solute and .100 g is solvent.
Please help!!!!!
You're absolutely right.
12.5 g ethylene glycol in 100 g H2O is 12.5 g solute in (12.5g + 100 g) = 112.5 solution. Then use density to convert grams solution to L soln.
To find the molarity, you first need to calculate the mass of the solution.
The mass of the solution is the sum of the masses of the solute (ethylene glycol) and the solvent (water). In this case, the solute mass is given as 12.5 g, and the solvent mass is given as 0.100 kg.
Note: 0.100 kg is equivalent to 100 g.
So, the mass of the solution = 12.5 g + 100 g = 112.5 g
Next, to find the volume of the solution, you need to consider the density of the solution. The density is given as 1.0 g/mL.
Density = Mass / Volume
Since the mass is 112.5 g, and the density is 1.0 g/mL, you can rearrange the equation to solve for the volume:
Volume = Mass / Density
Volume = 112.5 g / 1.0 g/mL = 112.5 mL
Now that you have the volume of the solution, you can convert it to liters by dividing by 1000 (1 L = 1000 mL).
Volume = 112.5 mL / 1000 = 0.1125 L
Finally, you can calculate the molarity using the formula:
Molarity = Moles of Solute / Liters of Solution
In this case, you need to convert the mass of ethylene glycol to moles. The molar mass of ethylene glycol (C2H6O2) is 46.07 g/mol.
Moles of ethylene glycol = mass / molar mass
= 12.5 g / 46.07 g/mol
Now you have all the values needed to calculate the molarity:
Molarity = Moles of ethylene glycol / Liters of Solution
= (12.5 g / 46.07 g/mol) / 0.1125 L
Calculate this expression to find the molarity.