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from wikipedia http://en.wikipedia.org/wiki/Humidity
Humid air is less dense than dry air because a molecule of water (m = 18) is less dense than a molecule of nitrogen(m = 28) and a molecule of oxygen (m = 32). About 78% of the molecules in dry air are nitrogen (N2). Another 21% of the molecules in dry air are oxygen (O2). The final 1% of dry air is a mixture of other gases. For any gas, at a given temperature and pressure, the number of molecules present is constant for a particular volume - see ideal gas law. So when water molecules (vapor) are introduced to the dry air, the number of air molecules must reduce by the same number in a given volume, without the pressure or temperature increasing. Hence the mass per unit volume of the gas (its density) decreases. Isaac newton discovered this phenomenon and wrote about it in his book Opticks.
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Why is the gas sulfur hexafluoride heavier then air?
The density of a gas is propotional to its molecular weight. Air is composed of primarily of nitrogen and oxygen, which have molecular weights of about 28 g/mol and 32 g/mol respectively. Sulfur hexafluoride has a molecular weight of about 146 g/mol, which would make it roughly 5 times denser than air.
Density of low molecular weight polyisobutylene?
The density of low molecular weight polyisobutylene (PIB) typically ranges from 0.87 to 0.92 g/cm3. The exact value may vary based on factors such as molecular weight and purity of the material. It is a generally low-density material.
Atmospheric serpuser is detemined by the temperature and density of the air and the amount of water vapor in it?
Yes, atmospheric pressure is determined by the combined effect of temperature, air density, and the concentration of water vapor present in the air. These factors influence the overall molecular motion and interactions within the atmosphere, directly impacting the pressure exerted by the air at a given location.
Which is thicker air and water vapour?
The density of dry air is higher than the density of water vapor. Using the ideal gas equation, p=(rho)(R*/M)T rho = pM/(R*T) M is the molecular weight of the substance. The average molecular weight of air is 28.8 g/mole, while for water vapor it's 18 g/mole, so dry air is more dense than water vapor by a factor of 28.8/18.
Is ethanol vapor lighter than air?
No, it has a higher molecular mass (46 g/mol) than air (28.7 g/mol)
What is the relationship between molecular mass and vapour density?
The relationship between molecular mass and vapor density is that they are proportional to each other. Vapor density is defined as the mass of a vapor relative to the mass of an equal volume of air, while molecular mass is the mass of a molecule of a substance. Therefore, a higher molecular mass will result in a higher vapor density.
What is vapour density of air?
The vapor density of air is the ratio of the mass of a certain volume of air to the mass of an equal volume of a reference gas, typically hydrogen or dry air. It is used to compare the density of a gas to that of another gas or to the average molecular weight of air. The vapor density of air is approximately 1.29, meaning that air is slightly heavier than the reference gas hydrogen.
Is hydrogen gas denser than air?
No, hydrogen gas is less dense than air. This is because hydrogen gas has a lower molecular weight compared to the average molecular weight of gases present in air, which makes it lighter and less dense.
What is the trend in density as you go down the group of noble gases?
The densities of the noble gases increase with increasing molecular mass. The increase in density is due to the increase in atomic mass. Helium is about one seventh the density of air and can be used in balloons and lighter-than-air craft. Xenon is about five times the density of air.
What is compressed portion of sound wave?
The compressed portion of a sound wave is called the compression phase. This is where air particles are squeezed together, resulting in higher pressure and increased molecular density. The compression phase is followed by the rarefaction phase, where the air particles spread out, resulting in lower pressure and decreased molecular density.
Why is the gas sulfur hexafluoride heavier then air?
The density of a gas is propotional to its molecular weight. Air is composed of primarily of nitrogen and oxygen, which have molecular weights of about 28 g/mol and 32 g/mol respectively. Sulfur hexafluoride has a molecular weight of about 146 g/mol, which would make it roughly 5 times denser than air.
Is carbondioxide heavier than air?
Yes, carbon dioxide is heavier than air. It has a molecular weight of 44 grams per mole, which is heavier than the molecular weight of air (approximately 29 grams per mole). This causes carbon dioxide to displace air and concentrate at lower levels.
How do you calculate density from molecular weight?
Density can be calculated from molecular weight using the formula density = (molecular weight) / (molar volume). Molar volume is the volume occupied by one mole of the substance and can be calculated using the ideal gas law or experimental data. Dividing the molecular weight by the molar volume gives the density of the substance.
What is the density of HMHDPE?
The density of high molecular weight high density polyethylene (HMHDPE) typically ranges from 0.945 to 0.965 grams per cubic centimeter.
What is the trend in density in noble gases?
The densities of the noble gases increase with increasing molecular mass. The increase in density is due to the increase in atomic mass. Helium is about one seventh the density of air and can be used in balloons and lighter-than-air craft. Xenon is about five times the density of air.
Can density be seen?
Density is not a visual quality. But we can infer information about density by observing. For example moist air is lighter than dry air - that is why the clouds condense at higher altitudes, not at ground level. {Explanation - H2O has an molecular mass of 28; O2 has an molecular mass of 32; N2 has an molecular mass of 34. Hence H2O vapour is lighter than O2 or N2.}
Is air more dense than oil?
No. density is based on molecular mass. Air is considered a gas. Gases have lower densities than liquids at 'room temperature'.
