Freezing point depression for dilute solution can be calculated using the formula: ΔT_f = K_f · c · i where K_f = cryoscopic constant of the solvent c = molality of solution, i..e. number os moles solute per kilogram solvent i = van't Hoff factor
The cryscopic constant for the solvent water is K_f = 1.853 °C/m
Glucose has a molar mass of: M = (6·12 + 12·1 + 6·16) g/mol = 180 g/mol So you dissolved n = 15.5 g / 180 mol = 8.61×10⁻² mol Hence molaltity of solution is c = 8.61×10⁻² mol / 0.245 kg = 0.3515 m
The van' Hoff factor gives you the number of particles in solution per particle dissolved. Since glucose does not dissociate, when it is dissolved in water, the van't Hoff factor for this solution is i = 1
So the freezing point depression for this solution is: ΔT_f = 1.853 °C/m · 0.3515 m · 1 = 0.65 °C
The freezing point of the solution equals freezing point of pure solvent minus freezing point depression: T_f = T_f° - ΔT_f = 0 °C - 0.65 °C = - 0.65 °C
Answer:
The molarity of this solution is 14.82 mol/dm3 or 14.82 mol/L
Explanation:
- Molarity is the number of mole present in 1 Litre of solution. Molarity of a solution is a term referred to as concentration of a solution. The unit of Molarity is Mol/dm3 or Mol/L.
- let us make an assumption that the volume of the ammonia solution is 1L or 1dm3. Also, 1L = 1000 mL.
Step 1: calculate the mass of the solution
Density = 0.90g/ml (from the question)
Density = mass/ volume
Therefore Mass = density x volume
= 0.90g/ml x 1000ml
mass = 900 g
Step 2: calculate the mass of NH3 present in the solution
Since the concentrated aqueous of ammonia is 28%, It signifies that 1000ml of the solution contains 28% Ammonia
Recall from the above calculation that the mass of 1000 ml of solution is 900 g.
Therefore the mass of ammonia will be 28% of 900 g
mass of NH3 = 0.28 x 900 g
= 252 g
Step 3: calculate the number of mole of NH3
mole = mass/ molar mass
molar mass of NH3 = 17 g/mol
Therefore mole of NH3 = 252/17
= 14.82 mol
Step 4: Calculate Molarity
Molarity = number of moles/ volume of solution in Litre (L)
Molarity = 14.82 / 1
Molarity = 14.82 mol/L
Answer: You will need mountaineering equipment such as ice axes and crampons, clothing such as gloves and headwear, and supplies such as food, a stove to thaw water and the food, and first aid materials.
Explanation: Please mark as brainliest lol!
Bestie since it’s Cl2, put 2 next to KCl. That means you need to 2 moles of K, so put 2 next to KI. That’s it
The answer is certain chemical symbols on the periodic table were named not anlyafter the people who discovered them. some of their chemical symbols were even taken from their Latin names. in sodium's case it was taken from it's original Latin name, natrium, as is na.