Name rhodium
Symbol Rh
Atomic Weight 102.90550
Atomic Number 45
CAS ID 7440-16-6
Group Number 9
Group Name Precious Metal
Period Number 5
Origin of Name Greek, rhodon = "rose"
Year Discovered 1803
Discovery Credits W. H. Wollaston at London, UK.
Class Metallic
Color Silvery White Metallic
Standard State Solid at 77 F & 298 K
Description Rare, lustrous, silvery, hard mental of the platinum group. Stable in air up to 875 K. Inert to all acids, attacked by fused alkalis. Used as a catalyst.

Diagnostic tests: 
There are no simple chemical tests for rhodium. The element is usually found as an alloy or a sulfide mineral with other platinum group metals. Atomic Absorption Spectroscopy is used for quantitative analysis and Energy Dispersive Analysis of X-rays (EDAX) is used for qualitative analysis.

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