Acids and Bases Quiz

dissociation

breaking apart into ions

Arrhenius acid

• a substance that produces H+ when dissolved in water

• this means according to this definition, all acids must have at least 1 hydrogen

• H+ is synonymous with the hydronium ion: H3O+

Properties of acids:

• acids have a sour taste and would burn if put onto skin

• when a strong acid is added to a strong base, they form water. This is called a neutralization reaction

• acids corrode metal, which means that when they react, hydrogen gas is formed

strong acids

HCI, HBr, HI, HNO3, H2SO4, HCIO4

Properties of Bases:

• Arrhenius base: a substance that produces OH- when dissolved

• Bases taste bitter and feel slippery to the touch

• when a base comes into contact with proteins, it denatures them

Strong bases

group 1 or group 2

pH

• a measure of how acidic or basic a substance is

  • pH of an acid: <7

  • pH of a base: >7

  • no units for pH

pH and pOH

pH= -log[H+]

pOH= -log[OH-]

relationship between pH and pOH:

pH + pOH= 14.00

Find pH

[H+] = 0.00576 M

Find pOH:

[OH-] = 0.0554 M

Undoing pH

[H+] = 10^-pH

Undoing pOH:

[OH-] = 10^-pOH

What is the molarity of H+ if the pH is 6.70?

What is the molarity of H+ if pOH is 3.57?

naming acids

• binary acids: H and 1 other element on periodic table

  • prefix: hydro-

  • suffix: -ic

    • ex: HCl —> hydrochloric acid

polyatomic acids

• H + polyatomic anion

• based off polyatomic ion name + ic

  • ex: HC2H3O2 - acetic acid

• oxyanions- keep prefix, change ending

  • ate 🡪 -ic

  • ite 🡪 -ous

    • ex: H2CO2 - carbonous acid

Ex. What is the pH and pOH of a 2.34 x 10^-5M HClO₄ solution?

pH = -log (2.34 x 10^-5 ) = 4.63

pH + pOH = 14.00

4.63 + pOH = 14.00

pOH = 9.37

Ex. What is the pH and pOH of a 7.9 x 10^-12M NaOH solution?

pOH = - log (7.90 x 10^-12 ) 

= 11.1

pH + pOH = 14.00 

  pH = 14.00 - 11.1

  = 2.9

Ex. The pOH of a solution is 10.25, what is the [H⁺]? The [OH^-]?

pH = 14.00- 10.25 

  = 3.75

[OH^-] = 10 ^{^ -10.25} 

 = 5.62 x 10^-11M
[H⁺] = 10 ^{^ -3.75} 

= 1.78 x 10 ^-4 M

Ex. What is the [H⁺] if the pH is 9.50? What is the [OH^-]? 

pOH = 14.00 - 9.50 

= 4.50

[H⁺] = 10 ^{^ -9.50}

   = 3.16 x 10 ^-10 M

[OH^-] = 10 ^{^ -4.50}

    = 3.16 x 10^-5 M

Titrations

Method of finding the unknown molarity of a solution by reacting it with a solution of known concentration.

Tips

• Never fill when buret is above your eye level. This is dangerous.

• The final solution should be the lightest pink possible. Use white paper underneath to help.

• you can use a first trial to go fast (approx result). then slow down your subsequent trials for more accurate results

What is the pH and pOH of a 2.34 x 10-5M

HClO4 solution?

pH = 4.631, pOH = 9.369

What is the [H+] if the pH is 9.50? What is the

[OH-]?

[H+] = 3.2 x 10-10 M

pOH = 4.50, [OH-] = 3.2 x 10-5 M

Bronsted-Lowery’s definitions

• acid-substance that donates an H+

• base-substance that accepts an H+

Conjugate acid

the acidic form of the original base (formed when the base accepts the H+)

conjugate base

the basic form of the original acid(formed when the acid donates the H)

Label the acid, base, conjugate acid, conjugate

base: NH3 + HClO 🡨🡪 NH4+ + ClO-

base

acid

conj acid

conj base

amphoteric

• a substance that can act as an acid or base

• can accept an H+ or give an H+

• ex: H2O

titrations

used to determine a unknown concentration

titrant

solution of known concentration

analyte

solution of unknow concentration

indicator

changes color:

• when pH changes

  • at the equivalence point

equipment

~Buret

-contains titrant

~Erlenmeyer flask

-contains analyte and indicator

~ring stand

~buret clamp

-attaches buret to ring stand