what are its properties?
Soft, silver-metallic, lustrous and highly crystalline transition metal.
Yttrium
Yttrium is a soft, silver-metallic, lustrous and highly crystalline transition metal in group 3. As expected by periodic trends, it is less electronegative than its predecessor in the group, scandium, and less electronegative than the next member of period 5, zirconium; additionally, it is more electronegative than lanthanum, but less electronegative than lutetium due to the lanthanide contraction. Yttrium is the first d-block element in the fifth period.

what is yttrium? Chemical element
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Yttrium [SEP] Properties
Yttrium is a soft, silver-metallic, lustrous and highly crystalline transition metal in group 3. As expected by periodic trends, it is less electronegative than its predecessor in the group, scandium, and less electronegative than the next member of period 5, zirconium; additionally, it is more electronegative than lanthanum, but less electronegative than lutetium due to the lanthanide contraction. Yttrium is the first d-block element in the fifth period. The pure element is relatively stable in air in bulk form, due to passivation of a protective oxide () film that forms on the surface. This film can reach a thickness of 10 µm when yttrium is heated to 750 °C in water vapor.