How many moles are in 6.21x1025 atoms of magnesium oxide?

55.56 moles of MgO

Explanation:

1 mole = avogadro number

if 6.21x10^25 atoms then molecules of MgO (equal numbers of Mg and O atoms)

= 0.5*6.21x10^25 = 3.105 molecules of MgO

So moles of MgO = 0.5*6.21*10^25/avogadro number = 55.56

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles

answer: h+ its less than oh

explanation: