How can we determine the valency of an element

- How can we determine the valency of an element from its group number in the periodic table
- How can we determine the valency of an element with the help of periodic table
- How do you determine the valency of an element
- How do we determine the valency of an element
- How can you determine the valency of an element
- How to determine the valency of an element
- How to determine the valency of an element that forms ionic compounds
- How do you determine the valency of an element what are negative and positive valency
- How do you determine the valency of an element in chemistry
- How does the valency of an element determined explain it with suitable example
- How does the valency of an element determine
- Determine the valency of an element x whose atomic number is 15