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Language of Chemistry — CHEMISTRY STD 8 — Question

ICSE BoardEnglish MediumSTD 8CHEMISTRYLanguage of Chemistry5 Marks
Question
What is variable valency ? Give two examples of elements showing variable valency.
✓

Answer

Certain elements exhibit more than one valency, that means they show variable valency.
Ferrous is written as Iron $\text{(II)}$ and Ferric is written as Iron $\text{(III)}.$
Metal Radicals Valency
Iron Ferrous $[$Iron $\text{(II)}]$
Ferric $[$Iron $\text{(III)]}$		 $2
3$
Copper Cuprous $[$Copper $\text{(I)}]$
Cupric $[$Copper $\text{(II)}]$		 $1
2$

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