Answer:
B. 0.075 m (NH4)3PO4
Explanation:
Our strategy here is to recall the van´t Hoff factor, i, for the colligative properties of electrolyte solutions which appears as the consequence that electrolytes disociate completely in their solutions in water.
Thus in this problem we need to determine i and then realize the one with the lowest freezing point will have the biggest i ( all the concentrations are equal) since
ΔTf = i m Kf
Substance van´t Hoff factor
Li I 2
(NH4)3PO4 4
NaIO4 2
KCN 2
KNO2 2
The correct answer is B. 0.075 m (NH4)3PO4
Answer:
Electrolytes are chemicals that break into ions (ionize) when they are dissolved in water. The positively-charged ions are called cations, while the negatively charged ions are called anions.
Strong electrolytes completely ionize in water. This means 100% of the dissolved chemical breaks into cations and anions.
Weak electrolytes partially ionize in water. Pretty much any dissociation into ions between 0% and 100% makes a chemical a weak electrolyte, but in practice, around 1% to 10% of a weak electrolyte breaks into ions.
If a substance doesn’t ionize in water at all, it’s a nonelectrolyte.
Explanation:
The answer is C : 15.7 m/s
Use the idea of : momentum before collision = momentum after collision
Before collision;
For car:mass=1.1×10^3, velocity=22
For truck:mass=2.3×10^3, velocity=0
After collision;
For car:mass=2.3×10^3, velocity=-11
For truck:mass=2.3×10^3, velocity=V
(1.1×10^3 × 22) + (2.3×10^3 × 0) = (1.1×10^3 × -11) + (2.3×10^3 × V)
24200 = -12100 + 2.3×10^3V
2.3×10^3V = 36300
V = 15.7 m/s
Is A “the density of the ice decreased as it melted”
