Question

what happens to the valency of elements across the period and down group ???​

Answer 1

Answer:

Valency. Valency in the periodic table across a period first increases and then decreases. There is no change going down a group. However, this periodic trend is sparsely followed for heavier elements (elements with atomic number greater than 20), especially for lanthanide and actinide series.

Answer 2

Answer:

• ᴠᴀʟᴇɴᴄʏ ɪɴ ᴛʜᴇ ᴘᴇʀɪᴏᴅɪᴄ ᴛᴀʙʟᴇ ᴀᴄʀᴏss ᴀ ᴘᴇʀɪᴏᴅ ғɪʀsᴛ ɪɴᴄʀᴇᴀsᴇs ᴀɴᴅ ᴛʜᴇɴ ᴅᴇᴄʀᴇᴀsᴇs. ᴛʜᴇʀᴇ ɪs ɴᴏ ᴄʜᴀɴɢᴇ ɢᴏɪɴɢ ᴅᴏᴡɴ ᴀ ɢʀᴏᴜᴘ. ʜᴏᴡᴇᴠᴇʀ, ᴛʜɪs ᴘᴇʀɪᴏᴅɪᴄ ᴛʀᴇɴᴅ ɪs sᴘᴀʀsᴇʟʏ ғᴏʟʟᴏᴡᴇᴅ ғᴏʀ ʜᴇᴀᴠɪᴇʀ ᴇʟᴇᴍᴇɴᴛs (ᴇʟᴇᴍᴇɴᴛs ᴡɪᴛʜ ᴀᴛᴏᴍɪᴄ ɴᴜᴍʙᴇʀ ɢʀᴇᴀᴛᴇʀ ᴛʜᴀɴ ), ᴇsᴘᴇᴄɪᴀʟʟʏ ғᴏʀ ʟᴀɴᴛʜᴀɴɪᴅᴇ ᴀɴᴅ ᴀᴄᴛɪɴɪᴅᴇ sᴇʀɪᴇs.