Answer:
1.583 moles
Explanation:
Rounded Atomic Mass of Au = 197 grams
Answer:
THE NORMAL BOILING POINT OF A SOLUTION CONTAINING 64.5 g OF QUINOLINE IN 500 g OF BENZENE IS 82.6 C
Explanation:
Boiling point = old boiling point + molarity * boiling point constant (Kb)
First, you calculate the number of moles of quinoline in the solution
number of moles = mass / molar mass
Since the molar mass of quinoline has been given as 129 g/mol
number of moles = 64.5 g / 129 g/mol
number of moles = 0.5 moles.
Next is to determine the molarity:
molarity = number of moles of solute / kilogram of solvent
molarity = 0.5 moles / 500/1000 kg
molarity = 0.5 / 0.5
molarity = 1 M
The new boiling point can then be calculated using the formula:
B. P = old B.P + Kb * molarity
B.P = 80.10 + 2.50 * 1
B.P = 80.10 + 2.50
B.P = 82.6 degree celsius
Answer:
Precipitation reactions are ones in which at least one of the reactants is in the aqueous phase (i.e., dissolved in water), and a solid forms on the product side which was not present on the reactant side. If all the reactants are solid, then a solid product forming should not be called a precipitate. To be called a precipitate, an insoluble product must form from within solution, either from a solid and solute interacting, or from an interaction strictly between solutes.
Explanation:
They do not change the nature of the substance unless a chemical change occurs along with the physical change. These may be irreversible, but the result is still composed of the same molecules. When you cut your hair, that is a physical change, even though you can't put the hair back on your head again