Dye of iodine is prepared by dissolving in ethanol , and 1% ( one percent ) of this solution contains 10 g of solute in 1000 g of solution
1) how many grams of solvent is there in the solution ?
2) how many moles of solute ( I2) is there?
3) what is the molality of 1% of this solution ?
and can we find the molarity of solution ?
1. 1% means 1g I2/100 g solution = 10g I2/1000g solution = 10g I2/(10g I2+ 990g ethanol)
2. mol I2 = grams/molar mass
3. m = mols/kg solvent = ?
You can convert to M if you know the density of the solution.
To answer these questions, let's break down the information given and use some basic concepts in chemistry.
1) How many grams of solvent are there in the solution?
Solvent is the component that dissolves the solute, so in this case, ethanol is the solvent. The solution is 1% iodine dissolved in ethanol. We know that 1% of the solution contains 10 grams of solute (iodine) in 1000 grams of the entire solution.
To find the grams of solvent, we need to subtract the grams of solute from the grams of the entire solution.
Grams of solvent = Total grams of solution - Grams of solute
Grams of solvent = 1000 g - 10 g
Grams of solvent = 990 g
Therefore, there are 990 grams of ethanol (solvent) in the solution.
2) How many moles of solute (I2) are there?
To calculate the number of moles of solute, we need to know the molar mass of iodine (I2). The molar mass of I2 is approximately 253.8 g/mol.
Now, we can use the mole-to-mass conversion to find the number of moles of iodine:
Number of moles = Mass of solute / Molar mass of solute
Number of moles = 10 g / 253.8 g/mol
Number of moles ≈ 0.039 moles
Therefore, there are approximately 0.039 moles of iodine (I2) in the solution.
3) What is the molality of 1% of this solution?
Molality (m) is defined as the number of moles of solute per kilogram of solvent. Since we know the amount of solute and solvent, we can calculate the molality.
Molality = Moles of solute / Kilograms of solvent
Moles of solute = 0.039 moles
Kilograms of solvent = 990 g ÷ 1000 = 0.99 kg
Molality = 0.039 moles / 0.99 kg
Molality ≈ 0.0394 mol/kg (rounded to four decimal places)
Therefore, the molality of 1% of this solution is approximately 0.0394 mol/kg.
As for the last question, "can we find the molarity of the solution?", the information provided does not allow us to directly calculate the molarity. Molarity (M) is the number of moles of solute per liter of solution. To find the molarity, we need to know either the volume of the solution or the concentration of the solute in terms of moles per liter.