Answer:
3) NaCl.
Explanation:
<em>∵ ΔTf = iKf.m</em>
where, <em>i</em> is the van 't Hoff factor.
<em>Kf </em>is the molal depression freezing constant.
<em>m</em> is the molality of the solute.
<em>The van 't Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved and the concentration of a substance as calculated from its mass. </em>
<em></em>
- For most non-electrolytes dissolved in water, the van 't Hoff factor is essentially 1.
<em>So, for sugar: i = 1.</em>
<em>∴ ΔTf for sugar = iKf.m = (1)(Kf)(2.0 m) = 2 Kf.</em>
<em></em>
- For most ionic compounds dissolved in water, the van 't Hoff factor is equal to the number of discrete ions in a formula unit of the substance.
For NaCl, it is electrolyte compound which dissociates to Na⁺ and Cl⁻.
<em>So, i for NaCl = 2.</em>
<em>∴ ΔTf for NaCl = iKf.m = (2)(Kf)(1.0 m) = 2 Kf.</em>
<em></em>
<em>So, the right choice is: 3) NaCl.</em>
<em></em>
Answer:
a scientific procedure undertaken to make a discovery, test a hypothesis, or demonstrate a known fact.
Answer:
B. 0.55 M
Explanation:
Step 1: Given data
- Moles of calcium chloride (solute): 1.5 mol
- Volume of solution: 2.75 M
Step 2: Calculate the molarity of the aqueous solution
The molarity is a way to express the concentration of a solution. It is equal to the quotient between the moles of solute and the liters of solution.
M = moles of solute / liters of solution
M = 1.5 mol / 2.75 L = 0.55 mol/L = 0.55 M
Answer:see the image for the structure of the allylic carbocation
Explanation:
When 2,4-hexanediene is protonated at the 5-position as shown in the image, a carbonation is formed which can be stabilized by resonance. The positive charge can be found on carbon 4 or carbon 2 due to resonance of the allylic carbonation. The both structures are shown and electron movements were depicted using curved arrow notation in the structures shown in the image attached.
