Barium hydroxide dissolves as follows. ba(oh)2(s) ? ba2+(aq) + 2oh- (aq) how many moles of ba(oh)2 are required to make 1.0 l of solution in which the ohconcentration is 0.050 m?

Determine the wavelength of the light absorbed when an electron in a hydrogen atom makes a transition from an orbital in the n=3 level to an orbital in the n=7 level.

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

When a spring is compressed, the energy changes from kinetic to potential. which best describes what is causing this change?