Topic 8: Acids and Bases

Question 1

Bronsted-Lowry Acid

Answer 1

proton (h+) donor

Question 2

Bronsted-Lowry Base

Answer 2

proton (h+) acceptor

Question 3

Lewis theory Acid

Answer 3

electron pair acceptor

Question 4

Lewis Base

Answer 4

electron pair donator

Question 5

enthalpy of neutralization

Answer 5

enthalpy change when an acid and a base react together to form 1 mole of h20

Question 6

acid + metal reaction

Answer 6

salt + hydrogen

Question 7

acid + base reaction

Answer 7

salt + water

Question 8

acid + carbonate reaction

Answer 8

salt + water + carbon dioxide

Question 9

neutralization reaction

Answer 9

exothermic reaction; when an acid and a base make salt and water

Question 10

meausuring pH methods

Answer 10

• using pH meter
• using universal indicator
• electrical conductivity
• H+ concentration

Question 11

strong acids

Answer 11

(weak conjugate bases; ionize and dissosiate completly in solution)

Question 12

strong acid examples

Answer 12

HCl
HNO3
H2SO4

Question 13

weak acid

Answer 13

partial dissociation/ionization in solution

strong conjugate bases

Question 14

weak acid examples

Answer 14

partially ionize/dissociate

• H2CO3
• H3PO4
• CH3COOH

Question 15

pH scale

Answer 15

pH + pOH= 14

7 is neutral

Question 16

pH formula

Answer 16

-log (H+)

10^-pH

Question 17

monoprotic vs. diprotic

Answer 17

monoprotic; 1 H ion (e,g, HCL)

diprotic; 2 H ions (e.g. H2SO4)

Question 18

how to distinguish between a strong or weak acid

Answer 18

1. electrical conductivity
2. rate of reaction
3. pH

Question 19

causes of acid depostion

Answer 19

• all rain water naturally acidic due to dissolved CO2 (carbonic acid)
• wet acid deposition
• dry acid deposition

Question 20

nitrogen oxides

Answer 20

(NOx)
origins; electiral storms, decomposition, bacteria ammonification, combustion
- react with water to form nitrous acid and nitric acid
- nitrogen and oxygen form nitrogen oxides

Question 21

sulfur oxides

Answer 21

(SOx)
origins; volcanoes and fossil fuel comustions
-reacts with water to form sulfiric acid

reaction of s+ o process;
- SO2–> SO3–> Acids

Question 22

effects of acid deposition on matierals

Answer 22

corrodes/oxidizes/erosion

Question 23

effects of acid deposition on plants

Answer 23

prvents growth of plants
access to nutrients limited
damage to plant roots
blocks stomata for gas exchange

Question 24

effects of acid deposition on water

Answer 24

eutrophication
ocean acidity
oxyggen depletion
animal suffer

Question 25

effects of acid deposition on human health

Answer 25

respiratory illnesses + eye irritations

- possible risk of corroded/broken buildings

Question 26

responses to acid deposition

Answer 26

1. lower NOx and SOx formation (use of catalytic converters better for environment)
2. switch to alternative energy soruces
3. ‘liming’ of lakes to neutralize acidity (e.g. calcium oxide)
4. post + pre combustion methods (hydrode sulfurization) and lower the temperature

Question 27

litmus effect

Answer 27

acid: pink

base; blue

Question 28

methyl orange effect

Answer 28

acid: red

base; yellow

Question 29

phenolphthalein effect

Answer 29

acid; colourless

base; pink

Question 30

precombustion methods of SO2

Answer 30

• hydrodesulfurization (HDS) is a catalytic process that removes sulfur from petroleum by reacting it with hydrogen to form H2S; this toxic gas is capture + converted into elemental sulfur for manufactural use of sulfuric acid
• for metal sulfide; wash sulfur by crushing it with coal + wahing with water

Question 31

post combustion methods of SO2

Answer 31

• flue-gas desulfurization

- react CaO or CaCO3 with SO2 to form neutral product; Calcium Sulfate

Question 32

reduction of NOx emissions

Answer 32

1. Catalytic converters in vehicles; hot gases mixed with air and passed over platinum catalyst to convert toxic emisions to harmless products
   2CO + 2NO—> 2CO2 + N2
2. Lower temperature combustion
   - formation of nitrogen monoxide reduced at lower temperature (reciruclate the exaust gases)