Easy and important what do you think is the most challenging aspect of using a microscope? what are the advantages and disadvantages of using a microscope to look at trace evidence?

Compare and contrast physical changes with chemical changes.

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

For each of the compounds below, show that the charges on the ions add up to zero. a. kbr b. cao c. li(2)o d. cacl(2) e. alcl(3)