the density of air at 25dergees C and 1 atmosphere of pressure is about 1.18 g/L. What happens to the dnesity of air as the temperature is increased. When the pressure is incrased?

To understand what happens to the density of air as the temperature and pressure change, let's break it down:

1. Temperature and Density:
As the temperature of air increases, the density decreases. This is because warmer air tends to expand, causing the same amount of molecules to occupy a larger volume, resulting in a decrease in density. Conversely, if the temperature decreases, the air contracts, and the density increases.

2. Pressure and Density:
When the pressure of air increases, the density also increases. This is because the molecules are compressed, occupying a smaller volume, which leads to an increase in density. Conversely, if the pressure decreases, the density decreases.

It's important to note that these relationships hold true as long as other factors, such as the composition of the air, remain constant.

To calculate the exact changes in density due to temperature and pressure variations, you can use the ideal gas law equation:

PV = nRT

Where:
P = Pressure
V = Volume
n = Number of moles of gas
R = Ideal gas constant
T = Temperature in Kelvin

By rearranging the equation, you can solve for density (ρ):

ρ = (PM) / (RT)

Where:
ρ = Density
P = Pressure
M = Molar mass of the gas
R = Ideal gas constant
T = Temperature in Kelvin

By plugging in the different values for temperature and pressure, you can determine the resulting density of air.

As the temperature of air increases, the density decreases. This is because the air molecules gain energy and move more rapidly, causing them to spread out and occupy a larger volume.

On the other hand, when the pressure is increased while keeping the temperature constant, the density of air also increases. This is because the air molecules are compressed into a smaller volume, leading to a higher density.

Overall, for a given amount of air, increasing the temperature will decrease its density, while increasing the pressure will increase its density.