Chem 129 Midterm 1

A Bronsted-Lewis Acid...

...will donate a proton to form a new covalent bond

Identify the conjugate base in the following reaction

H₂SO₃(aq) + HPO₄²⁻(aq)→H₂PO₄⁻(aq) + HSO₃⁻(aq)

HSO₃⁻

The strength of a metal hydrateacids is dependent on the ___________ of the central atom

Charge Density

Which acid is the strongest?

HBr, H₂S, HCl, HF

HBr

What is the Ka expression for NH₄⁺?

[NH₃][H₃O⁺]/ [NH₄⁺]

Which compound would have the highest molar solubility?

Strontium Sulfate (Ksp=3.2x10⁻¹⁶)

Silver Cyanide (Ksp=2.2x10⁻¹⁶)

Calcium Chromate (ksp=1.4x10⁻⁸)

Copper (I) Chloride (Ksp= 1.9x10⁻⁷)

Copper (I) Chloride

(larger Ksp usually means more soluble)

the pH scale is dependent on...

... the auto ionization of water

The units for solubility are...

... g/100mL

If the initial concentration of a solution is 2.1x10⁻³M for an acid with Ka=7.4x10⁻⁴, would the "x is small" approximation work?

no, the Ka value is too similar to the initial concentration.

Which trends dictate the strength of oxoacids:

-electronegativity of the central atom

-the difference between number of oxygens and number of hydrogens

What is the solubility of strontium fluoride in water? (ksp= 2.6x10⁻⁹)

10.88 mg/100mL

How much barium is left in solution when I mix 55mL of 0.20M barium nitrate with 45mL of .33M sodium chromate(the ksp for barium chromate is 2.1x10⁻¹⁰)

...

a 0.4M acidic solution has an initial pH of 3.67. What is the Ka of the weak acid?

1.14x10⁻⁷

What is the pH of a 0.18M solution of Sodium Lactate? (for lactic acid ka=1.4x10⁻⁴)

8.55

What is the pH of a solution made by mixing 200 mL of .45M HCl with 201mL of .45M NaOH?

11.05