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45Rh

Element 45

Rhodium

Transition metals

Rhodium (Rh) is in the d-block of the periodic table — group 9, period 5.

Rhodium is a chemical element with symbol Rh and atomic number 45.

Key data

Atomic number
45
Atomic mass
102.906 u
Group / Period
9 / 5
Block
d-block
Phase at STP
Solid
Density
12.41 g/cm³
Melting point
1963.8 °C
Boiling point
3694.8 °C
Electron configuration
[Kr] 4d8 5s1

Periodic table block

Rhodium is in the d-block (group 9, period 5). Elements land in the d-block when their highest-energy electrons fill a d subshell — these are the transition metals in the middle of the table.

s-blockp-blockd-blockf-block

New to this? Periodic table blocks explained: s, p, d, and f

Common uses

  • Catalytic converters
  • Jewelry plating
  • Mirrors

Discovery

Year: 1803

Discovered by: William Hyde Wollaston

Frequently asked questions

What is the atomic number of Rhodium?

Rhodium has atomic number 45. Its symbol is Rh and its atomic mass is 102.906 u.

What category of element is Rhodium?

Rhodium is classified as transition metals. It sits in group 9, period 5 of the periodic table.

What block of the periodic table is Rhodium in?

Rhodium is in the d-block (group 9, period 5). Its highest-energy electrons occupy the d subshell — you can see this in its electron configuration, [Kr] 4d8 5s1.

What is Rhodium used for?

Common uses of Rhodium include: Catalytic converters, Jewelry plating, Mirrors.

When was Rhodium discovered?

Rhodium was discovered in 1803 by William Hyde Wollaston.

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