Find the number of grams in 4.26 X 1024 formula units of MgCl2.

Explanation:

Number of moles of Cl atoms in 1.20 1024 Formula units of magnesium chloride mgcl2

The number of moles of Cl is twice as much, because the ratio of Cl in MgCl2 to MgCl2 is 2:1. Therefore, there are 12 moles of Cl. There are 7.22×1024 atoms Cl in 3.61×1024 formula units of MgCl2

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

the answer for sodium is 0.186

the answer for rubidium is 0.251