Which is an example of a chemical change? a pan of water boils. a candle burns. a teaspoon of salt dissolves. a burner gets red hot

Asample of silver (with work function ? = 4.52 ev) is exposed to an ultraviolet light source (? = 200 nm), which results in the ejection of photoelectrons. what changes will be observed if: silver is replaced with copper (? = 5.10 ev) more photoelectrons ejected no photoelectrons are emitted fewer photoelectrons ejected more energetic photoelectrons (on average) less energetic photoelectrons (on average)

For ai it's atomic number is 13 and it's mass number is 27 how many neutrons does it have

One does not belong why? ice, gold ,wood ,diamond and table salt