No, but there is less oxygen. This makes breathing harder.
Air pressure decreases the higher up you go, according to Boyle's law volume and pressire are inversely proportional, so volume will increase.
yes, as you go farther up from the sea level, the air will become thinner.
Air pressure decreases as you go up.
Yes, as you go up a mountain, the air pressure will become less. This is because the weight of the air above decreases as you gain elevation, resulting in lower atmospheric pressure.
The air pressure slowly decreases as you rise in altitude.
When an air mass encounters mountains it cannot go through them, nor down into the ground, so the only direction left to go is up.
Most often, the air at higher elevations is cooler than the air at lower elevations. The act of your climbing the mountain has no effect on it.
Air pressure at any altitude is determined by how strongly gravity forces the surrounding air molecules together and downward. The higher the altitude the less pull gravity exerts on the air molecules, and consequently, the air pressure decreases. So, as you climb a mountain, the higher you go, the lower the ambient air pressure.
As you go up a mountain, the air pressure decreases, which can lead to lower oxygen levels. This may cause difficulties breathing and can lead to altitude sickness. The temperature also tends to drop as you ascend.
From what I recall, the air at the bottom of a mountain is usually warmer, wetter, and more oxygenated. The air at the top gets less of these three depending on as high up as you go.
A 1inch by 1inch column of air from the edge of the atmosphere to sea level weighs 14.7 pounds, 80% of that is in the Troposphere. As you go up, the air within that column has less mass, making the air "thinner", and air pressure goes decreases.
As altitude increases, the air pressure decreases which causes the air to expand and cool down. This drop in temperature is known as the lapse rate. Additionally, mountains are often exposed to high winds which can further contribute to lower temperatures.