Answer:
- <u><em>0.2 mol of CaCl</em></u><em><u>₂</u></em>
Explanation:
<em>Freezing point</em> depression of a solution, when a nonvolatile solute is dissolved in a solvent, is a colligative property, which means that it depends on the number of particles of solute dissolved.
The equation is:
![\Delta T_f=m\times k_f\times i](https://tex.z-dn.net/?f=%5CDelta%20T_f%3Dm%5Ctimes%20k_f%5Ctimes%20i)
Where:
- ΔTf is the decrease in the freezing point
- m is the molal concentration
- kf is the molal freezing point depression constant, which depends on the solvent
- i is the nan't Hoff factor, which accounts for the dissociation of ionic compounds.
Since the volume is the same for all the solutoins, the molal concentration will be higher for those solutions with more number of moles. Then, cross out the first two choices.
Since CaCl₂, in ideal conditions, dissociates into 1 Ca²⁺ ion and 2 Cl⁻ ions, the van't Hoff factor is 3, while for the molcecular C₆H₁₂O₆ it is 1.
Thus, the lowest freezing point will be produced by the sample of 0.2 mol of CaCl₂.
Answer:
Theory of Plate Tectonics
Explanation:
Scientists especially Geologists study and record seismic data and volcanic activities in order to support the theory of plate tectonics.
The theory of plate tectonics suggests that the earth is broken into slabs called the lithosphere that moves over the fluid asthenosphere below.
- The use of seismic data presents scientists with a way of vertically looking deep into the earth.
- Volcanic activities also presents us with the kind of materials down within the earth.
- Also, coupled with this data, scientists use GPS sensors to monitor the rate of movement of the earth.
- When studying plate tectonics, it invariably culminates in the study of sea floor spreading and theory of continental drift.
Answer: it has 2 parts
Explanation:
Firstly, plant cells have a cell wall that surrounds the cell membrane, whereas animal cells do not. Plant cells also possess two organelles that animal cells lack: chloroplasts and a large central vacuole
Answer:
2.67g of NH4Cl are required
Explanation:
Molarity is an unit of concentration in chemistry defined as the moles of solute (In this case, NH4Cl), per liter of solution.
To prepare 100mL of a 0.50M are required:
100mL = 0.100L * (0.50 moles / L) = 0.0500 moles NH4Cl
As molar mass of NH4Cl is 53.491g/mol:
0.0500 moles * (53.491g / mol) =
<h3>2.67g of NH4Cl are required</h3>