What is the approximate percentage and partial pressure of argon (Ar) in the atmosphere at sea level?

Argon constitutes about 0.93% of the Earth's atmosphere at sea level, which is typically rounded to approximately 1%. To determine the partial pressure of a gas in the atmosphere, you can use Dalton's Law, which states that the partial pressure of a gas is equal to its mole fraction in the mixture multiplied by the total atmospheric pressure. At sea level, the average atmospheric pressure is about 760 mmHg.

So, if we take the fraction of argon (0.0093) and multiply it by the atmospheric pressure (760 mmHg):

0.0093 x 760 mmHg ≈ 7.06 mmHg, which is commonly rounded to approximately 7.6 mmHg.

Therefore, the correct answer accurately reflects the actual concentration and partial pressure of argon in the atmosphere at sea level. This understanding is crucial in medical gas administration to prevent any potential complications related to the presence of trace gases during procedures.