Question

the density
of air in the mountains is called​

Answer 1

What is the density of air in English units?

It also changes with variation in atmospheric pressure, temperature and humidity. At 1013.25 hPa (abs) and 15°C, air has a density of approximately 1.225 kg/m³ (or 0.00237 slug/ft³), about 1/1000th that of water according to ISA (International Standard Atmosphere).

Answer 2

The density of air or atmospheric density, denoted ρ (Greek: rho), is the mass per unit volume of Earth's atmosphere. Air density, like air pressure, decreases with increasing altitude. It also changes with variation in atmospheric pressure, temperature and humidity. At 1013.25 hPa (abs) and 15°C, air has a density of approximately 1.225 kg/m³ (or 0.00237 slug/ft³), about 1/1000th that of water according to ISA (International Standard Atmosphere).[citation needed]

Air density is a property used in many branches of science, engineering, and industry, including aeronautics;[1][2][3] gravimetric analysis;[4] the air-conditioning[5] industry; atmospheric research and meteorology;[6][7][8] agricultural engineering (modeling and tracking of Soil-Vegetation-Atmosphere-Transfer (SVAT) models);[9][10][11] and the engineering community that deals with compressed air.[12]

Depending on the measuring instruments used, different sets of equations for the calculation of the density of air can be applied. Air is a mixture of gases and the calculations always simplify, to a greater or lesser extent, the properties of the mixture.

Temperature