Assuming you mean “20 materials that conduct heat” — these are thermal conductors:
- Silver
- Copper
- Aluminium
- Gold
- Brass
- Bronze
- Steel
- Iron
- Cast iron
- Zinc
- Nickel
- Lead
- Tin
- Platinum
- Tungsten
- Magnesium
- Titanium
- Mercury
- Graphite
- Diamond
Key idea: Heat conduction is energy transfer through a material, usually by particles vibrating and — in metals — by free electrons. That is why metals such as copper, silver and aluminium conduct heat well. Graphite and diamond are non-metals but can also conduct heat because of their structure. Diamond is an especially good thermal conductor.
Quick check: Most of the list are metals, so they are expected to be good heat conductors. Materials such as wood, plastic, rubber and foam are thermal insulators, so they would not belong on this list. Do not handle mercury — it is toxic; it is included only as a scientific example.
