Answer:
65.2
Explanation:
For this task, we will use formula C = n/V,
where C is molar concentration (amount of substance per unit volume). The most commonly used unit for molarity is the number of moles per litre with the unit symbol mol/L, or differently M
n is the amount of substance. The most commonly used unit for the amount of substance is mole with the unit symbol mol
V is the volume of substance. The most commonly used unit for the volume is dm3 which equals to 1L - liter.
In the task we were given the following information:
V = 295.0 mL = 0.2950 L
C = 0.221 M
n = ?
C= n/V ⇒ n = C x V
n = 0.2950 L x 0.221 mol/L
n = 0.065195 mole
We will now transform moles to millimoles because we need to calculate the millimoles of barium chlorate
1 mole = 1000 millimoles ⇒ 0.065195 moles = 65.195
Now, we only need to round this answer to 3 significant digits, so the answer would be 65.2