The substance x and y had retention times of 16.4 and 17.63 minutes on a 30 cm column. unretained species had 1.30 minutes retention time. the peak widths (wi) were 1.11 and 1.21 min, respectively. calculate column resolution, average number of plates, and plate height.

Column Resolution

Rs = 2[ (tr) y - (tr) x]/[Wx + Wy]

= 2[17.63 - 16.4] / [1.11 + 1.21] = 1.06

Average no. of plates in the column for substance x

N = 16 (tr / W) ^2

N = 16 (16.4/1.11) ^2

N = 3490 plates

Average no. of plates in the column for substance y

N = 16 (tr / W) ^2

N = 16 (17.63/1.21) ^2

N = 3397 plates

Plates Height

H = L/N

For substance x

H = 30/3490

H = 0.00916905 cm/plate

For substance y

H = 30/3397

H = 0.00883132 cm/plate