How many molecules of stearic acid are present in 2.00 mL of a 0.25 mM solution of stearic acid?
mM=mol/mL
so, take the product of (0.25mol/mL)*(2 mL) to get mol
then, multiply by Avogadro's number (6.022 x 10^23 molecules/ mol)
3.0E23
To determine the number of molecules of stearic acid present in the solution, we need to use the formula:
Number of molecules = Concentration (moles/L) × Volume (L) × Avogadro's number
First, let's convert the given volume from milliliters (mL) to liters (L). We know that:
1 L = 1000 mL
So, 2.00 mL is equal to 2.00 × 10^(-3) L (division by 1000).
Next, we need to convert the concentration from millimolar (mM) to moles per liter (mol/L). We know that:
1 mM = 1 × 10^(-3) mol/L (since "milli" means 10^(-3))
Therefore, the concentration of the stearic acid solution is 0.25 × 10^(-3) mol/L.
Now, we can substitute the values we have into the formula:
Number of molecules = (0.25 × 10^(-3) mol/L) × (2.00 × 10^(-3) L) × (6.022 × 10^23 molecules/mol)
Calculating this will give us the number of molecules of stearic acid present in the given solution.