What is the Molecular Density of Air?
Numerous sources give the number of molecules of air per liter, at STP, as approximately 2.5E22. A liter contains 1E3 cubic centimeters, and a cubic meter contains 1E6 cubic centimeters. Thus a cubic meter contains 1E3 liters, and the number of molecules in a cubic meter is approximately 2.5E25. Best regards, G.R.Dixon, www.maxwellsociety.net
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Being a gas, the density of air can vary a lot, depending on its temperature and pressure. At sea level, it is usually close to 1.2 kilograms per cubic meter.
Air has both mass and density, just like all forms of matter. A liter of air at sea level and at 0 Celsius has a mass of about 1.29 grams. Its density would then be 1.29 grams… per liter.
Like all mass, air does have density. Density is calculated by the formula M/V=D, where M is Mass, V is Volume and D is Density. Mass is the scientifically correct term for …weight, weight varies depending on the gravity, mass is constant. Volume is the area that a substance takes up, a Litre is a measurement of volume. Air is composed of various gases, on Earth it's something like 21% Oxygen 78% Nitrogen, along with water vapor, carbon dioxide, and other gases like hydrogen and methane. Even the lightest of gases have mass, so they must have a density.
Air is a mixture of gases.. so it desn't have any appropriate molecular structure.. The composition of air is :. Nitrogen (N 2 ): 78.09%. Oxygen (O 2 ): 20.95%. Argon (Ar):… 0.93%. Carbon dioxide (CO 2 ): 0.038%. Others (less than 0.002% each): Neon (Ne), Helium (He), Krypton (Kr), Hydrogen (H 2 ), Xenon (Xe).
I'm not exactly positive. But if you know the volume in grams and the mass (giving you density), then you should be able to figure out the molecular weight. The mass is the sa…me as the molar mass, which I would assume is the same as the molecular weight, but I'm not positive.
The average molecular weight of dry air is 28.96 g/gmol.
the ratio between the mass of one mole of a substance and its volume is the molecular density....
vapor density =density of gas/density of hydrogen gas =mass of a certain vol. of gas/mass of same vol. of hydrogen gas =mass of n molecules of gas/mass of n molecules of hy…drogen gas =mass of 1 molecule of gas/mass of 1 molecule of hydrogen gas =molecular mass of gas/molecular mass of hydrogen gas =molecular mass/2 2 x vapor density=molecular mass
without density it would be pretty hard for air to exist. Here is a breakdown: first of all we know air exists, and that it exists in 3 dimentions of space. In order for som…ething to exist there must be space in which it can exist, this is Volume (V). Since air is a form of matter, it must have mass (m) we now have two variables which define air's presence, m and V, mass of air (m), and the space it inhabits, (V). since so much mass has to exist in a certain amount of space, the relationship between mass and space is proportional. You will have so many kilograms of air in so many meters cubed of space. Just as you have 12 eggs in 1 carton, or 4 tires per car, density tells you how many Kg of air per meter cubed. (in metric) density = m/V bottom line: any mass will have density, because it occupies space, and density simply represents how much mass is occupying how much space.
Air density is the mass of air per unit volume, which changes by temperature, humidity, and elevation. Changes in air density will change its pressure. At mean sea level an…d 20Â°C, air has a density of approximately 1.2 kg/m 3 .
Say if you had a closed bottle of air, that contained exactly 100mols, in which there would be 6.023E25 moleculs. Of these molecules, about 21% of would purely as Oxygen O2 at…oms, and about 78% would exist as Nitrogen N2 atoms, with the remaining 1% being trace amounts of other gases. The atoms are all independent of each other, some moving faster, some moving slower.
It is the weighted average of the individual molecular weights of the components oxygen and nitrogen. Generally speaking, air is composed of 21% oxygen and 79% nitrogen. Thus …the average molecular weight of air is calculated as follows: MW air = (.21)*(MW O2) + (.79)*(MW N2)
the given molecular weight is divided by volume