Answer:
168°C is the melting point of your impure sample.
Explanation:
Melting point of pure camphor= T =179°C
Melting point of sample =
= ?
Depression in freezing point = 
Depression in freezing point is also given by formula:

= The freezing point depression constant
m = molality of the sample = 0.275 mol/kg
i = van't Hoff factor
We have:
= 40°C kg/mol
i = 1 ( non electrolyte)




168°C is the melting point of your impure sample.
Http://www.lcmrschooldistrict.com/demers/cbphysicalscience/Chp%208-3%20Solubility%20and%20Concentrat...
This website helped me understand the concept.
Answer:
A
Explanation:
in a lewis structure, it shows the connectivity of a molecule as well as how many and where the valence electrons are located.
The answer is A! Heat energy is thermal energy. To remember all Energy use M.E.L.T.S!
M- Mechanical energy
E- Electrical energy
L- Light energy
T- Thermal energy
S- Sound energy