Response:
of 
can be found in 39.5 grams of .
Clarification:
Atomic weights: P= 31, F= 19,
The molar mass equals 1 atomic weight of P + 5 atomic weights of
F= 31+5 × 19
= 31+95
=126 g/mole
The number of moles in 39.5 gm of
equals 
= 
=0.3134 moles
1 mole of any substance encompasses
0.3131 moles comprises 0.3134
Thus, of can be found in 39.5 grams of .
The answer is C: hydrogen bonds. Explanation: The surface tension and the capacity for heat storage in water are due to its hydrogen bonds. Water molecules have a strong attraction to one another through hydrogen bonding. These bonds are continuously forming and breaking within water molecules. The result of this hydrogen bonding is surface tension, which allows water to have a greater capacity for heat retention. Consequently, during the night, the temperature on Earth drops much faster than it does for water, as water gradually releases heat, helping maintain a moderate atmospheric temperature at night.
