The atmospheric pressure in a lab is calculated as 1.3 atm. If oxygen gas contributes 62% of this atmospheric pressure, determine its mass (in g) dissolved at room temperature in 25 L of water. The Henry's Law Constant for oxygen in water at this temperature is 5.3 x 10^-5 M/atm.

Next, apply Henry's Law to find the concentration of dissolved oxygen in water. Henry's Law states that the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the liquid. Use the formula: \( C = k \cdot P \), where \( C \) is the concentration, \( k \) is the Henry's Law constant (5.3 x 10^{-5} M/atm), and \( P \) is the partial pressure of oxygen calculated in the previous step.