the pH Scale
What pH value is considered neutral? Give one example of a neutral substance.
7; pure water
Acids produce which ion in water?
H₃O⁺ (Hydronium)
In a solution of sugar dissolved in water, which is the solvent?
Water
What is the formula for mass percent?
mass of solute/total mass of solution x 100
What is the Tyndall effect?
Colloids scatter light
On the pH Scale, which range of numbers indicates a basic (alkaline) solution?
8-14
Bases produce which ion in water?
OH⁻ (Hydroxide)
What is an unsaturated solution?
A solution contains 25 g of sugar mixed with 175 g of water. What is the mass percent of sugar?
12.5%
Whipped cream is an example of what type of colloid: emulsion, gel, foam, or sol?
Foam (think air bubbles!)
A solution has a pH of 10. Compared to a solution of pH 9, how many times more basic is the pH 10 solution?
10 times
When an acid and base undergo neutralization, what substance is formed?
Salt
A supersaturated solution is created by:
Cooling a saturated solution after dissolving solute in hot solvent.
A rubbing alcohol solution contains 40 g of alcohol and has a total mass of 200 g. Calculate the percent volume of alcohol. (Round to nearest hundredths place)
20%
Oil and vinegar dressing separates when left standing because it lacks a ...?
Emulsifier
pH is a measure of what type of ion? The more of this ion you have, the more acidic a solution is.
Hydrogen
A Bronsted-Lowry acid is a: proton donor or acceptor?
Proton donor
Adding sugar to an ice cream mixture causes the freezing point to:
Lower or decrease
At 60 °C, a supersaturated solution is prepared by dissolving 75 g of potassium nitrate (KNO₃) in 115 g of water. What is the mass percent of potassium nitrate?
39.47%
In mayonnaise, what is the continuous phase and what is the dispersed phase? Name both.
Continous phase= water; Dispersed phase= oil
What is the role of a buffer?
Keep pH steady.
The Lewis Theory says acids: accept or donate electrons?
Accept electrons
Adding salt to water causes the boiling point to do what?
Increase
A student prepares a solution with 25 g salt + 225 g water. What is the mass percent?
10%
Are emulsifiers hydrophilic, hydrophobic, or both?
Both