Answer:
Explanation:
Using freezing point depression formula,
ΔTemp.f = Kf * b * i
Where,
ΔTemp.f = temp.f(pure solvent) - temp.f(solution)
b = molality
i = van't Hoff factor
Kf = cryoscopic constant
= 1.86°C/m for water
= (0 - (-5.58))/1.86
= 3.00 mol/kg
Assume 1 kg of water(solvent)
= (3.00 x 1)
= 3.00 mol.
Answer:
89.4%
Explanation:
Initially, there is 5.0 of the acetanilide in 100 mL of water, then the solution is chilled at 0ºC. The solubility represents the amount that the solvent (water) can dissolve of the solute (acetanilide). So, at 0ºC, 100 mL of water can dissolve till 0.53 g of the compound, the rest will precipitate and will be recovered.
So, the mass that is recovered is 5.0 - 0.53 = 4.47 g
The percent recovery is:
(4.47/5)x100% = 89.4%
Answer:
Geothermal power comes from Earth's internal heat
Explanation:
The description applied to power sources tends to match the names applied to the source of energy. Sometimes Latin, or other word derivations are used.
For example, "hydro-" refers to water, so it is no surprise that hydroelectric power comes from the movement of water. Of course, "nuclear" refers to the nuclei of the atoms that are split to release energy in a nuclear power plant. Similarly, "geo-" refers to Earth, and "thermal" refers to heat, so "geothermal" energy is the name given to energy derived from Earth's heat.
Answer:
C
Explanation:
This is essentially one of the several safety measures in the chemical laboratory. This particular approach is one used in the case of fire eventualities.
A is wrong
This is because in the advent of a fire incident, it is necessary to evacuate the building as a whole. Meeting in the hallway is still within the building which is not the right thing to do when there’s a fire outbreak. Occupants are expected to leave the building immediately
B. Is also wrong. Taking time to pack your belongings might make you be caught in the inferno. It is expected that you leave the building at once
