An aqueous solution of potassium sulfate exhibits colligative properties. Colligative properties are properties that depends on the concentration of a substance in a solution. These properties are freezing point depression, vapor pressure lowering, osmotic pressure and boiling point elevation. For this problem we use the concept of freezing point depression since we are given the freezing point of the solution. Freezing point depression is as:
ΔT = -k(f) x m x i
-2.24 - 0 = -1.86 x m x 3
<span>m = 0.4014
Thus, the molality of the solution is 0.4014.</span>
Answer:
15.4 g of sucrose
Explanation:
Formula to be applied for solving these question: colligative property of freezing point depression. → ΔT = Kf . m
ΔT = Freezing T° of pure solvent - Freezing T° of solution
Let's replace data given: 0°C - (-0.56°C) = 1.86 C/m . m
0.56°C / 1.86 m/°C = m → 0.301 mol/kg
m → molality (moles of solute in 1kg of solvent)
Our mass of solvent is not 1kg, it is 150 g. Let's convert it from g to kg, to determine the moles of solute: 150 g. 1kg/1000g = 0.150 kg
0.301 mol/kg . 0.150kg = 0.045 moles.
We determine the mass of sucrose, by the molar mass:
0.045 mol . 342 g/1mol = 15.4 g
Answer:
They can both be used in an electric circuit.
Explanation:
Though conductors and insulators are very different from each other but still they have a similarity that "they can both be used in an electric circuit".
Conductors are the material that allows electricity to flow and insulators have high resistance and do not allow electricity to flow.
Both conductors and insulators are used in an electric circuit as conductor is used in wires, batteries and bulb to flow current while insulators are used in insulation of wire, switches, plugs and etc. Combination of them makes the circuit shock free.
Hence, the correct answer is "They can both be used in an electric circuit."
Answer:
I would say the last one because mass is not created nor destroyed.
Explanation:
