<span>This change is called BOILING.</span>
How many grams of solute do you have to weigh to prepare 250 ml KMnO4 solution with a concentration of 0.500 mol / L
Answer:
19.75g
Explanation:
Given parameters:
Volume of KMnO₄ = 250mL or 0.25L
Concentration of solution = 0.5mol/L
Unknown:
Mass of solute or KMnO₄ = ?
Solution:
To solve this problem, we need to find the number of moles first.
Number of moles = Concentration x volume
Number of moles = 0.5mol/L x 0.25L = 0.125mol
So;
Mass in grams = number of moles x molar mass
Molar mass of KMnO₄ = 39 + 55 + 4(16) = 158g/mol
Mass in grams = 0.125 x 158 = 19.75g
How about putting one battery in the freezer while putting another by a radiator or something that gives off heat. Leave them for an hour, then place them in an object that uses batteries and time how long it takes for it to die: Note: It may take many hours for the battery to fully deplete.
The correct answer is d!!
