We must know that molarity is a unit for concentration and it is expressed as:
molarity = moles / liters
The molarity is 100 millimolar, or 0.1 molar. The volume is 250 ml, or 0.25 liters. Using the formula above, we find the moles of benzoic acid required.
moles = molarity * liters
moles = 0.1 * 0.25
moles = 0.025
Next, we know that the molar mass for benzoic acid is 122.12 g/mol and the moles of a substance are given by:
moles = mass / molar mass
mass = moles * molar mass
mass = 0.025 * 122.12
mass = 3.05 grams
You will need to weigh out 3.05 grams of benzoic acid
Staying healthy
that is the answer
1 mole --------------------------- 6.02 x 10²³ molecules
( moles lithium ) --------------- 1.2 x 10²¹ molecules
( moles lithium ) = (1.2 x 10²¹ ) x 1 / ( 6.02 x 10²³ )
= 1.2 x 10²¹ / 6.02 x 10²³
= 2.0 x 10⁻³ moles of lithium
Answer D
hope this helps!
The balanced reaction would be as follows:
<span>3NaOH + H3PO4 --> Na3PO4 + 3H20
We are given the concentration and the amount of the reactants to be used. We use these values for the calculations as follows:
</span><span>How many mL of .225 M NaOH will react with 4.568g H3PO4?
4.568 g (1 mol / 98 g) ( 3 mol NaOH / 1 mol H3PO4 ) ( 1 L / .225 mol NaOH ) = 0.621 L or 621 mL of .225 NaOH</span>
