Answer:
To determine the number of grams of KOH present in the solution, we need to use the concept of stoichiometry and the balanced chemical equation for the reaction between HCl and KOH. The balanced equation is as follows:
HCl + KOH → KCl + H2O
From the equation, we can see that one mole of HCl reacts with one mole of KOH to produce one mole of KCl and one mole of water. Therefore, the number of moles of HCl can be calculated using the formula:
moles of HCl = volume of HCl solution (in L) × molarity of HCl
Given that the volume of HCl solution is 45.1 mL (or 0.0451 L) and the molarity of HCl is 0.118 M, we can substitute these values into the formula:
moles of HCl = 0.0451 L × 0.118 M = 0.00532 moles
Since the stoichiometry tells us that one mole of HCl reacts with one mole of KOH, we can conclude that there are also 0.00532 moles of KOH in the solution.
To convert moles to grams, we need to use the molar mass of KOH. The molar mass is calculated by adding up the atomic masses of each element in the compound:
K: 39.10 g/mol
O: 16.00 g/mol
H: 1.01 g/mol
Molar mass of KOH = (39.10 g/mol) + (16.00 g/mol) + (1.01 g/mol) = 56.11 g/mol
Now, we can calculate the mass of KOH using the formula:
mass of KOH = moles of KOH × molar mass of KOH
Substituting the values:
mass of KOH = 0.00532 moles × 56.11 g/mol = 0.298 g
Therefore, there must be approximately 0.298 grams of KOH present in the solution.
Step-by-step explanation: