What is the ph of 8.1x10^-5 m hclo4 solution

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)

What’s a special glass that most beakers are made of

Needthe meter is the standard unit for: 1) height 2) length 3) weight 4) mass