Answer:

Explanation:
Here, we want to calculate the number of moles of methane in the container
From the ideal gas law:

where:
P is the pressure inside the container which is 3 atm
V is the volume of the container which is 2 L
R is the molar gas constant which is 0.0821 Latm/mol.k
T is the temperature in Kelvin (we convert the temperature in Celsius by adding 273 : 273 + 77 = 350 K)
n is the number of moles that we want to calculate
Substituting the values, we have it that:
Answer:
c
Explanation:
and that's bc it will not share stay the same
Magnetic attraction and evaporation are the answers
We are given with the mass of pure iron that reacts with oxygen to form an oxide which has a given mass as well. the mass of oxygen reacted is 8.15-6.25 g or 1.9 grams. THen we convert the mass of the reactants to moles. Iron is equal to 0.1119 moles and oxygen is equal to 0.1188. We divide each number to the less amount. Hence iron is 1 and oxygen is approx 1. The empirical formula hence is FeO or ferrous oxide or Iron (II) oxide.