Molarity=moles/liters. Take 42.9 g CaCl2 and divide it by the molar mass of CaCl2 which is 110.98. You get .387 moles. Finally divide .387 moles/ 45 L = .0086 M CaCl2
Answer:- The correct answer is B. measuring the height of a building.
Explanations:- Insects and ants are very small. So, meter is not the right unit of measure their length. Their lengths would be measure in mm that is millimeters. So, options A and C are not good.
The distance between two cities is mostly too much so it's measured in kilometers or miles. So, D is also not good.
Height of buildings is measured in meters and so the correct option is B.
Answer :
1.80 x 10^-4 moles/liter OH-
Explanation:
pH = 3.58 ; [H3O+] = 10^-3.58 = 2.63 x 10^-4 moles/liter
pH = 4.08 ; [H3O+] = 10^-4.08 = 8.32 x 10^-5 moles/liter
One needs to remove:
2.63 x 10^-4 moles/liter – 8.32 x 10^-5 = 1.80 x 10^-4 moles H3O+/liter
According to the equation: H3O+ + OH-=⇒ 2H2O
Moles/ liter of OH- needed:
1.80 x 10^-4 moles H3O+/liter x 1 mole OH-/1mole H3O+ = 1.80 x 10^-4 moles/liter OH-
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