First let us calculate for the molar mass of ibuprofen:
Molar mass = 13 * 12 g/mol + 18 * 1 g/mol + 2 * 16 g/mol
Molar mass = 206 g/mol = 206 mg / mmol
Calculating for the number of moles:
moles = 200 mg / (206 mg / mmol)
moles = 0.971 mmol = 9.71 x 10^-4 moles
Using the Avogadros number, we calculate the number of
molecules of ibuprofen:
Molecules = 9.71 x 10^-4 moles * (6.022 x 10^23 molecules
/ moles)
<span>Molecules = 5.85 x 10^20 molecules</span>
Answer:
89.04 g of NaNO₃.
Explanation:
We'll begin by converting 838 mL to L. This can be obtained as follow:
1000 mL = 1 L
Therefore,
838 mL = 838 mL × 1 L / 1000 mL
838 mL = 0.838 L
Next, we shall determine the number of mole of NaNO₃ in the solution. This can be obtained as follow:
Volume = 0.838 L
Molarity = 1.25 M
Mole of NaNO₃ =?
Mole = Molarity × volume
Mole of NaNO₃ = 1.25 × 0.838
Mole of NaNO₃ = 1.0475 mole
Finally, we shall determine the mass of NaNO₃ needed to prepare the solution. This can be obtained as follow:
Mole of NaNO₃ = 1.0475 mole
Molar mass of NaNO₃ = 23 + 14 + (16×3)
= 23 + 14 + 48
= 85 g/mol
Mass of NaNO₃ =?
Mass = mole × molar mass
Mass of NaNO₃ = 1.0475 × 85
Mass of NaNO₃ = 89.04 g
Therefore, 89.04 g of NaNO₃ is needed to prepare the solution.
It should be rounded to 1 so I'm guessing true
