How much Pb(NO3)2 would need to be added to 100 mL of water to make a saturated solution at 40°C.

70g of Pb(NO3)2 would need to be added

Explanation:

As you can see in the solubility graph of lead nitrate, Pb(NO₃)₂, the solubility of this salt (That is, the maximum amount of the salt that can be dissolved in 100g of the solvent producing a homogeneous solution) is 70g in 100g of water = 70g of the salt in 100mL of water.

A saturated solution is also defined as solubility: The maximum amount of a solute that can be dissolved in a solvent.

That means:

70g of Pb(NO3)2 would need to be added

the only liquid elements at standard temperature and pressure are bromine (br) and mercury (hg). although, elements caesium (cs), rubidium (rb), francium (fr) and gallium (ga) become liquid at or just above room temperature.

explanation:

water at room temperature is flowing through a pipe with pressure taps located 10 ft apart along one section of the pipe, which are connected to a mercury (s=13.6) manometer.