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
.
Response: 2. When molecules with different speeds collide, heat is transferred from the faster ones to the slower ones.
Clarification: I hope this was useful!:)