Study the following unbalanced half-reaction. which equation represents the balanced half-reaction? h2o2 > h2o
e- + h+ + 2h2o2 h2o
2e- + 2oh- + h2o 2h2o2
2e- + 2h+ + h2o2 2h2o
3e- + 2h+ + 2ho- 4h2o
4e- + h2o2 2h2o +4e-

Calculate the number of molecules present in 0.750 mol of mgo.

There are 6.022, 104 atoms of hg in 1 mole of hg the number of atoms in 45 moles of hg can be found by multiplying 4.5 by 6.022, 102 which is the number of atoms in 4.5 moles of hg, correctly written in scientific notation with the correct number of significant figures? 0 21,109 0 21,100 271, 1024 27.099, 100 mark this and retum save and exit submit

If you chip a tooth, most likely you will go to the dentist to have the missing material filled in. currently the material used to fill in teeth is a polymer that is flexible when put in, yet is hardened to the strength of a tooth after irradiation with blue light at a wavelength of 461 nm. what is the energy in joules for a photon of light at this wavelength?