How many jouls are required to boiling 21.1 g of water at 100 c

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )

Use the table to identify the phase and phase changes of the elements under the given conditions. write the name of the substance, phase, or phase change

3) in peaches, [oh]=3.16x10-11 m a) find [h+ ] b) what is the ph? c) is the solution acidic, basic, or neutral?