True or False: Colloids made only of liquids exist. Explain.

Identify the type of colloidal dispersion that is one solid in another.

White gold is an alloy made up of gold and palladium. A bar of 14-karat gold has a density of 16.5 g/cm³ and contains 58.3% gold and 41.7% palladium by mass. What is the molar concentration of gold in the solution?

Starting with solid Ba(NO₃)₂, how would you prepare 2.50 L of 0.150 M aqueous solution of Ba(NO₃)₂?

A 100 proof (50% V/V) Scotch whisky is about 8.60 M ethanol (C₂H₅OH). Calculate the volume of ethanol needed to make a 750 mL solution that would be as strong as scotch whiskey assuming a density of 0.789 g/mL of ethanol.

Serotonin is a type of chemical messenger known as a neurotransmitter. It plays an important role in regulating a variety of body functions and feelings. In an experiment, rats are dosed with 1.5 mg/kg of a new drug and it showed an increase in serotonin in their brains by 0.35 mM after just 5 minutes. Calculate the molecules of serotonin produced in this amount of time if the rat's brain was measured to be 4.50 mm³. 

Water softeners are used to replace metal ions such as Ca²⁺ and Mg²⁺ in hard water with Na⁺. Calculate the moles of Na⁺ needed to replace these ions in 5 L of hard water with 0.035 M Ca²⁺ and 0.011 M Mg²⁺

An antiseptic solution is made by 2.3% antiseptic (MW = 556.94 g/mol) in water. It has a density of 0.9873 g/mL. Calculate the molarity of the antiseptic solution.

Lets say you have a solution of table salt (NaCl) dissolved in water. What would happen to the concentration of the solution as it boils? Explain your answer with a drawing.

a) decreases

b) increases

c) stays the same

d) not enough info