What mass of nacl is contained in 24.88 g of a 15.00% by mass solution of nacl in water?

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)

Pbco3 –> pbo+ co2. how many liters of carbon dioxide gas is produced from the decomposition of 32 grams of lead (ll) carbonate?

You may expect bonds between two atoms which each have n covalent lonic metallic hydrogen