Question
(c) A piece of potassium has a mass of 1.564 g. (i) Calculate the number of moles in this piece of potassium. (relative atomic mass of potassium=39.1) __ (ii) The piece of potassium was reacted with water. The total volume of the solution produced was 5.0dm^3 Calculate the concentration of the solution produced in moldm^-3 If you did not get an answer for (c)(i) use the value 0.06 for the number of moles. (2)
Answer
4.3
(271 Votes)
Malcolm
Veteran · Tutor for 11 years
Answer
## Step 1: Calculate the number of moles in the piece of potassium.
## Step 2: Calculate the concentration of the solution produced.
Explanation
## Step 1: Calculate the number of moles in the piece of potassium.The number of moles in a given mass of a substance can be calculated using the formula:###
where:-
is the number of moles,-
is the mass of the substance, and-
is the molar mass of the substance.Given that the mass of the potassium (
) is 1.564 g and the relative atomic mass of potassium (
) is 39.1 g/mol, we can substitute these values into the formula to find the number of moles.## Step 2: Calculate the concentration of the solution produced.The concentration of a solution can be calculated using the formula:###
where:-
is the concentration of the solution,-
is the number of moles of solute, and-
is the volume of the solution.Given that the number of moles of potassium (
) is the result we obtained from step 1 and the volume of the solution (
) is 5.0 dm³, we can substitute these values into the formula to find the concentration of the solution.