To convert the mass of an atom from atomic mass units (a.m.u.) to kilograms (kg), we can use the following conversion factor:
1 a.m.u. = 1.66054 × 10^(-27) kg
Given that the mass of an H atom is 1.008 a.m.u., we can calculate its mass in kilograms as follows:
Mass in kg = (Mass in a.m.u.) × (Conversion factor)
Mass in kg = 1.008 a.m.u. × 1.66054 × 10^(-27) kg
Mass in kg ≈ 1.674 × 10^(-27) kg
Therefore, the mass of an H atom is approximately 1.674 × 10^(-27) kg.