Question

Aluminium is used in thermite welding because

Answer 1

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┗─━─━─━─━∞◆∞━─━─━─━─┛

➙ Aʟᴜᴍɪɴɪᴜᴍ ɪꜱ ᴜꜱᴇᴅ ɪɴ ᴛʜᴇʀᴍɪᴛᴇ ᴡᴇʟᴅɪɴɢ ʙᴇᴄᴀᴜꜱᴇ:-
━━━━━━━━━━━━━━━━━━━━━━━

[1] Iᴛ ɪꜱ ꜱᴛʀᴏɴɢ ʀᴇᴅᴜᴄɪɴɢ ᴀɢᴇɴᴛ.

[2] Iᴛ ɪꜱ ꜱᴛʀᴏɴɢ ᴏxɪᴅɪꜱɪɴɢ ᴀɢᴇɴᴛ.

[3] Iᴛ ɪꜱ ᴄᴏʀʀᴏꜱɪᴏɴ ʀᴇꜱɪꜱᴛᴀɴᴛ.

Answer 2

In thermite welding aluminium powder is used along with ferric oxide.

Aluminium  has more affinity towards oxygen and it reduces ferric oxide to elemental iron during welding and also produces lot of heat.

The molten elemental iron thus formed will seal the broken parts to have a strong bonding.