CHEM: CHEMICAL EQUILIBRIUM (PART II)

Question 1

pH < 7, sour, turn litmus red, clear in
phenolphthalein indicator

Answer 1

Acids

Question 2

pH > 7, bitter, turn litmus blue, pink in
phenolphthalein, slippery

Answer 2

base

Question 3

• Substance that, when dissolved in water,
  increases the concentration of hydrogen ions

Answer 3

Acid (+)

Question 4

• Substance that, when dissolved in water,
  increases the concentration of hydroxide ions

Answer 4

Base (-)

Question 5

BRONSTED-LOWRY

• Proton donor; (proton is positive; capable of
  donating proton because of the presence of
  hydrogen ions)
• Must have a removable (acidic) proton

Answer 5

acid (+)

Question 6

BRONSTED-LOWRY

• Proton acceptor (negative)
• Must have a pair of nonbonding electrons

Answer 6

Base (-)

Question 7

acts as a Brønsted–Lowry base and abstracts
a proton (H+) from the acid.
• As a result, the conjugate base of the acid and a
hydronium ion are formed.

Answer 7

water

Question 8

From the Latin word conjugare, meaning “to join
together.”

Answer 8

conjugate

Question 9

is a proton donor; base is proton acceptor
• Reactions between acids and bases always yield
their conjugate bases and acids.

Answer 9

acid

Question 10

can serve as an acid and base [neutral]

Answer 10

water

Question 11

Components of water =

Answer 11

= hydrogen ions and
hydroxide ions

Question 12

(t or f)

water is amphoteric

Answer 12

true

Question 13

can serve as acids or bases

Answer 13

Amphoteric

Question 14

Chemical equilibrium equation of water (Kw);
walang denominator since hindi kasama ang
liquid (aqueous and gas lang ang kasama)
• This is referred to as ___________

Answer 14

autoionization.

Question 15

(t or f)

Temperature is a factor

Answer 15

true

Question 16

equilibrium favors reactants.

Answer 16

Small k

Question 17

refers to the measurement of the
strength of an acid or base.

Answer 17

pH

Question 18

comes to us from “portenz of hydrogen” –
portenz means strength and the hydrogen’s
chemical symbol is H.

Answer 18

pH

Question 19

is measured using the pH scale which runs
numerically from 0 to 14.

Answer 19

pH

Question 20

(t or f)
pH

• 0 – 7 is the region of acids (acidic solutions)
• 7 is perfectly neutral (as pure water would be)
• 7-14 is the region of bases (alkaline solutions)

Answer 20

true

Question 21

(t or f)
• The pH scale ranges from 0-14. A pH of 7 is perfectly
neutral like pure water.
• As you go away from seven and count down toward
zero – you are getting more and more acidic.
• As you count up from seven toward fourteen – you
are getting more and more basic.

Answer 21

true

Question 22

(t or f)
• The pH scale is based on a logarithm to the base 10
which means that each step along the pH scale
represents a change in the strength of the acid or
base by 10x

Answer 22

true

Question 23

(t or f)

• So, for acids, an acid with a pH of 3 is ten times
stronger than an acid of pH 4. (101)
• An acid with a pH of 2 is one thousand times
stronger than an acid of pH 5. (103 = 10 x 10 x 10)
• Bases operate by the same rule of measure.

Answer 23

true

Question 24

measures the amount of hydrogen ions released
by the acid when placed in a solution.

Answer 24

pH

Question 25

• When an acid is placed in a solution, it releases the hydronium or hydrogen (H+) ions and these ions attach themselves to the water molecules (H2O) to make the____________________

Answer 25

hydronium ion (H3O+).

Question 26

formula of pH

Answer 26

pH = – log [H3O+]

Question 27

measures the strength of an acid but it does not do the same for a base.

Answer 27

pH

Question 28

is a hydrogen ion acceptor so when you put it in water – it doesn’t form the hydronium ion – it forms the hydroxide ions (OH–) because it takes an H+ from the water.

Answer 28

base

Question 29

formula for pOH is:

Answer 29

pOH = – log10[OH–]

Question 30

blossoms in pink or blue, depending on soil pH. In acidic soils, the flowers are blue; in alkaline soils, the flowers are pink

Answer 30

Hydrangea macrophyll

Question 31

(t or f) - Litmus paper ▪ “Red” paper turns blue above ~pH = 8 ▪ “Blue” paper turns red below ~pH = 5

Answer 31

true

Question 32

- Often, in titration,______________ is used [from colorless to pink in a basic medium]

Answer 32

phenolphthalein

Question 33

is used to measure the pH of a substance. • is a chemical detector for hydronium ions (H3O+) or Hydrogen ions (H+) causes the colour of the solution to change depending on the pH.

Answer 33

indicator

Question 34

(t or f) • Common indicators are congo red, phenolphthalein, methyl orange, phenol red, bromothymol blue, bromocresol green and bromocresol purple.

Answer 34

true

Question 35

used to measure the pH

Answer 35

pH meter

Question 36

consists of a special measuring probe (a glass electrode) connected to an electronic meter that measures and displays the pH reading.

Answer 36

pH meter

Question 37

strong acid • Reactions involving the dissociation of strong acids can be written with a regular_______________, because the equilibrium lies very far to the right, i.e. favoring the products (the dissociated ions).

Answer 37

forward arrow

Question 38

(t or f) - To know if it is aqueous or liquid, check if it has charges - If it does have charges, it is an aqueous [acids or bases] - If it is water, it is liquid

Answer 38

true

Question 39

(t or f) Water is not included in the acid-dissociation equilibrium expression because the [H2O] has no effect on the equilibrium [liquid form]

Answer 39

true

Question 40

(t or f) • As the Ka value of an acid increases, so does the strength of the acid. By definition: • strong acid: Ka > 1 • weak acid: Ka < 1

Answer 40

true