Is hydrogen dioxide (water) always produced when an acidic solution is mixed with a basic solution?

There are 6.022 x 10^23 atoms of hg in 1 mole of hg. the number of atoms in 4.5 moles of hg can be found by multiplying 4.5 by 6.022 x 10^23 a. 2.7 x 10^24 b. 27 x 10^23 c. 2.71 x10^24 d. 27.099 x 10^23

As changes in energy levels of electrons increase, the frequencies of atomic line spectra they emit

Complete each row of the table below by filling in the missing prefix or missing exponent.