Physical Science Review #5 Solutions, Acids, Bases

Types of Mixtures Heterogeneous=different composition throughout Suspension Big Particles, Settle to the Bottom Colloids & Emulsions Small particles, don’t settle to the bottom Homogeneous= same composition throughout Solutions Very small particles Two parts: Solute: What gets dissolved, smallest amount Solvent: What does the dissolving, largest amount Water is universal Solvent

Polarity Polar Molecules: everything is not shared equally Non Polar Molecules: everything is shared equally Polar dissolves polar Nonpolar dissolves nonpolar Water is Polar Oil is Non-Polar

Saturation Unsaturated= not full, can add more solute Saturated = Full, cannot add more solute Supersaturated = more than full, can add more solute than normal because of more heat or pressure

Solubility Solubility = how well something dissolves into a liquid Concentration = how much solute is dissolved in solution Measured in Molarity (m) Find Molarity by moles / Liters Example: Find the molarity of a solution using 52 moles and 1500 mL.

Molarity Example #2 How many grams of NaF do you need to make 2 liters of a 3 M solution?

Acids & Bases Acids Bases Usually have H at beginning of formula pH is below 7 Turn litmus paper red Sour taste Usually have OH at end of formula pH is above 7 Turn litmus paper blue Bitter taste slippery

Weak vs Strong Strong = breaks into all ions (all things are charged) Acid breaks into H+ Base breaks into OH- Weak = NOT all into ions (some things remain as compounds)

Concentrated vs Dilute Concentrated= A lot of stuff dissolved in solution Dilute= Not a lot of stuff dissolved in solution

pH scale Ranges 1-14 Acids 0-below 7; bases above 7-14 Ex. How much more acidic is a pH of 2 than 5?

Calculating pH Examples: Find the pH of a solution with an H+ concentration of 0.000001 M Find the pH of solution with a H+ concentration of 1.0 x 10-11 M Find the pH of a solution if it contains 0.0006 moles and .006 L.

H+ concentration Find the H+ concentration if the pH is 5

Neutralization reactions Acid + Base  Salt + Water Does not always mean pH=7 but closer to 7 Equal amount of Strong Base + Strong Acid = pH 7 Equal amount of Strong Base + Weak Acid = pH >7 Equal amount of Weak Base + Strong Acid = pH <7