<Tr> <Td> 21 </Td> <Td> 17 </Td> <Td> chlorine </Td> <Td> Cl </Td> <Td> 500 </Td> <Td> 130 </Td> <Td> 170 </Td> <Td> 450 </Td> <Td> 145 </Td> <Td> </Td> </Tr> <Tr> <Td> 22 </Td> <Td> 24 </Td> <Td> chromium </Td> <Td> Cr </Td> <Td> 100 </Td> <Td> 100 </Td> <Td> 140 </Td> <Td> 350 </Td> <Td> 102 </Td> <Td> 26,000,000 </Td> </Tr> <Tr> <Td> 23 </Td> <Td> 37 </Td> <Td> rubidium </Td> <Td> Rb </Td> <Td> 300 </Td> <Td> 90 </Td> <Td> 60 </Td> <Td> </Td> <Td> 90 </Td> <Td> </Td> </Tr> <Tr> <Td> 24 </Td> <Td> 28 </Td> <Td> nickel </Td> <Td> Ni </Td> <Td> </Td> <Td> 80 </Td> <Td> 90 </Td> <Td> 190 </Td> <Td> 84 </Td> <Td> 2,250,000 </Td> </Tr>

Which metal has the largest abundance in earth crust