Respuesta :
Avagadros number states that 1 mol of any substance is made of 6.022 x 10^23 units
These units could be atoms making up elements or molecules making up compounds
Therefore 1 mol of CoCl2 is Made of 6.022 x 10^23 molecules of CoCl2
Molar mass of CoCl2 is 130 g/mol
Therefore 1 mol of CoCl2 weighs 130 g
So 130 g of CoCl2 contains 6.022 x 10^23 Molecules of CoCl2
Then 240 g of CoCl2 contains - 6.022 x 10^23 / 130 g x 240 g = 1.11 x 10^24 molecules of CoCl2
Answer is 1.11 x 10^24 molecules of CoCl2
The molecules that are in 240 grams of cobalt(ii) chloride COC2 is 1.112 x10^24 molecules
calculation
find the number of moles = mass/molar mass\
molar mass of CoCl2 = 58.9 + 35.5 x2 = 129.9 g/mol
moles= 240g/129.9 g/mol =1.8476 moles
by use of Avogadro's constant
that is 1 mole= 6.02 x10^23 molecules
1.8476 moles=? molecules
by cross multiplication
1.8476 moles x 6.02 x10^23 molecules/ 1moles =1.112 x10^24 molecules