You are given a sample of an unknown element. Describe 4 tests or observations you could make to determine whether or not it was a metal. [Say what...

You could first test to determine whether the sample conducts heat and electricity. Metals conduct heat and electricity much better than non-metals.

To test for electrical conductivity, you could make a circuit with a battery and a light bulb and place the sample in the conduction path. If you are able to power the bulb, the sample is conducting electricity.

To test the sample's ability to conduct heat, try placing it in a glass of ice water. After a few minutes, take it out and feel if the sample is now cold. If so, this is an indication that the sample conducts heat and is more likely to be a metal. 

Observe the sample visually for luster (shininess). Metals tend to be more shiny than non-metals. 

Test the malleability of the sample by striking it with a hammer. Metals are highly malleable (they deform under pressure instead of cracking). If you can flatten the sample with a hammer, it is likely a metal. If it cracks or becomes a powder, it is likely a non-metal.