Answer is: synthesis.
Chemical reaction: Ba + F₂ → BaF₂.
Synthesis is type of reaction where two or more compounds (in this reaction barium and fluorine) react to form one product (in this reaction BaF₂).
BaF₂ - barium fluoride, salt, <span>white cubic crystals, soluble in methanol and ethanol.</span>
I think the answer is c not completely sure
<span>The escape of gas through a small hole in a container is called effusion. This phenomenon happens when the diameter of the hole is small enough compared to the mean free path of the gas particles. This is governed by Graham's Law which states that the rate of effusion is inversely proportional to the molecular weight of the gas.</span>
V1 = 30 mL
P1 = 760 torr
P2 = 1520 torr
V2 = ?
applying Boyle's Law
P1*V1 = P2*V2
760 torr * 30 mL = 1520 torr * V2
V2 = 760 torr * 30 mL / 1520 torr
( C ) is correct