Answer:

Explanation:
As can be seen in the Figure in a face-centered cubic unit cell you have:
- Six halves of atoms
- Eight 1/8 of atom (1 in each corner)
In total:

Now, each side of the cell is 234 picometers (2.34e-8 cm) long


Atoms per cm3:


Expressing in mass:


Answer:
you work out the moles by finding the grand formula mass them you divide the actual mass by the grand formula mass: 25/160 (my grand formula mass is probably slightly different from yours) which I got 0.15625 then I times it by 32(O2) and I got 5. but my periodic table is different. it's whole numbers. ;-)
Explanation:
4.44
They should probably wear gloves. A pH of 2.0 is a very strong acid, and it can easily irritate their hands. They should also remember to NEVER touch their face, mouth, etc. and to keep all chemicals on the laboratory table.
Answer: an element with a high electronegativity and an element with a single valence electron