Answer:
The answer IS 0.0000035505. Hope it helps!
Explanation:
The mass of oxygen and hydrogen must be equal to the mass of the substance they create the water. So if the hydrogen is 2.8 g the oxygen must account for the rest of the mass. Basically just subtract 25.4-2.8=mass of oxygen
Answer:
"The number of air molecules above a surface determines air pressure. As the number of molecules increases, they exert more pressure on a surface, and the total atmospheric pressure increases. By contrast, if the number of molecules decreases, so too does the air pressure."