Arrange the following in the order of increasing mass (atomic mass: O = 16, Cu = 63, N = 14)
I. one atom of oxygen
II. one atom of nitrogen
III. `1 xx 10^(-10_` mole of oxygen
IV. `1xx 10^(-10)` mole of copper

Options

A. II lt I lt III lt IV
B. I lt II lt III lt IV
C. III lt II lt IV lt I
D. IV lt II lt III lt I

Answer

A

Explanation

I. Mass of 1 atom of oxygen
` = (16)/(6.022 xx 10^23)`
`= 2.66 xx 10^(-23) g `
II. Mass of 1 atom of nitrogen ` = (14)/(6.022 xx 10^23)`
` = 2.32 xx 10^(-23)g `
III. Mass of `1 xx 10^(-10) ` mol of oxygen
`= 16 xx 10^(-10) g`
IV. Mass of ` 1xx 10^(-10) ` mol of copper ` = 63 xx 10^(-10) g `
`therefore ` order of increasing atomic mass :
`II lt II lt III lt IV`