A solution contains 12 g of glucose in 240 mL of solution. What is the mass/volume % of the solution? 5.0% (m/v). Calculate the grams of KCl in 225 g of an 8.00 % (m/m) KCl solution
Answer: because a mole is based on Avogrado's number, which is 6.02 x 10²³ particles. It isn't possible to directly count that many particles at a time.
<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles.
45.6 g Au ( 1 mol / 196.97 g ) ( </span>6.022 x 10^23 atoms / mole ) = 1.39x10^23 atoms Au
Answer:
The answer to your question is MgSO₄ 5H₂O
Explanation:
Data
mass of MgSO₄ = 2.86 g
mass of H₂O = 2.14 g (5 - 2.86)
Process
1.- Calculate the molecular mass of the compounds
MgSO₄ = 24 + 32 + (16 x 4) = 120
H₂O = 16 + 2 = 18
2.- Convert the grams obtain to moles
120 g of MgSO₄ --------------- 1 mol
2.8 g ---------------- x
x = (2.8 x 1)/120
x = 0.024 moles
18 g of H₂O --------------------- 1 mol
2.14 g -------------------- x
x = (2.14 x 1)/18
x = 0.119
3.- Divide by the lowest number of moles
MgSO₄ = 0.024/0.024 = 1
H₂O = 0.119/ 0.024 = 5
4.- Write the molecular formula
MgSO₄5H₂O
Answer:
126.5g
Explanation:
n=<u>m</u><u> </u>
M
where n is moles
m is mass of substance
M is molar mass
molar mass of sodium is 23g/mol
m=nM
m=5.5(23)
m=126.5