Why are some mystery elements easier to identify than others?

They give colors to their salts.

Explanation:

When the reaction occurs and the formation of salts taken place then some elements give distinct colors to their salts while the reaction taking place.

So when we look out these elements we can find that mystery elements by defining with their colors.

Therefore, it is easy to identify some mystery elements because of their colors by looking at them.

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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