Answer:
measuring the mass of metal used in a reaction
Convert Mg to grams
1g =1000mg what about 3.91 Mg
= 3.91mg x 1g/1000mg= 3.91 x10^-3 g
moles= mass/molar mass
that is 3.91 x10^-3g /99 g/mol=3.95 x10^-5moles
concentration= moles / vol in liters
that is 3.95 x10^-5/100 x1000= 3.94 x10^-4M
equation for dissociation of CUCl= CUCl----> CU^+ +Cl^-
Ksp=(CU+)(CI-)
that is (3.95 x10^-4)(3.95 x10^-4)
Ksp= 1.56 x10^-7
Answer:
1.2×10² mmole of Na₂S₂O₃
Explanation:
From the question given above, the following data were obtained:
Volume = 0.6 L
Molarity = 0.2 mol/L
Mole of Na₂S₂O₃ =?
Molarity is simply defined as the mole of solute per unit litre of water. Mathematically, it is expressed as:
Molarity = mole /Volume
With the above formula, we can obtain the number of mole of Na₂S₂O₃ in the solution as illustrated below:
Volume = 0.6 L
Molarity = 0.2 mol/L
Mole of Na₂S₂O₃ =?
Molarity = mole /Volume
0.2 = Mole of Na₂S₂O₃ / 0.6
Cross multiply
Mole of Na₂S₂O₃ = 0.2 × 0.6
Mole of Na₂S₂O₃ = 0.12 mole
Finally, we shall convert 0.12 mole to millimole (mmol). This can be obtained as follow:
1 mole = 1000 mmol
Therefore,
0.12 mole = 0.12 mole × 1000 mmol / 1 mole
0.12 mole = 120 = 1.2×10² mmole
Thus, the chemist added 1.2×10² mmole of Na₂S₂O₃
