Question

what is mass of oxygen(16u) in kgs

Answer 1

We have to following conversion between atomic mass unit (u) and kilogram (kg)

1 u ≈ 1.66 × 10−27 kg

so,

in case of oxygen atom, atomic mass = 16 u, so, in kg

16 u = 16 × 1.66 × 10−27 kg

thus,

16 u = 26.56 × 10−27 kg

26.56 × 10−27 kg is also equal to 2.656 × 10−26 kg