Day 16 - Acid Rain, Day 15: Danube River, Day 15 - Neutralization, Day 14 - Acids & Bases-pH scale, Day 13 - Properties of Acids & Bases, Day 1 - 5.1 Properties & Changes (PG 175-178), Day 2: Trends in the Periodic Table, Lewis Dot Diagrams, Day 3= i...

What

any precipitation(rain, snow, fog) that has become acidic from reacting with compounds in atmosphere
-Any precipitation that has pH less than normal rain pH
-acid rain pH= 5.6
-emissions of sulfur and nitrogen compounds
-clean/Unpolluted rain=slightly acidic
-CO2(l) + H2O(g)-> H2CO (aq)=carbonic acid
-carbonic acid + water = some hydronium ions (H3O+)
-extra acidity from reaction of primary air pollutants (mostly sulfur oxides and nitrogen oxides with water in air=strong acids) like sulfuric and nitric acid.

How

pollutants: sulfur dioxide (fossil fuels) & nitrogen oxides (vehicle engines) + water=acids before precipitating

main sources

vehicles and industrial and power generating plants

Sulfur Dioxide

-most impt gas
-clear, colourless
-strong choking odour
-from coal burning industry, generate electricity, mining & refining metals, fossil fuel combustion
Process: more O reaction=2SO3+ water droplets=sulfuric acid

Nitrogen Oxides

-nitrogen oxides oxidized go from nitric acid=more b/c strict laws
-from cars that burn fossil fuels
-internal engine temp.=N2+O2->2NO
-POllution control tech now reverses= NO-> N+O
-some NO escapes to atmosphere
=reacts w. O=2 NO
-NO=Smog
-NO+water=nitric acid + NO

Natural

-princip. Volcanoes and biological process that occur on land, and water bodies
-major biological source of sulfur= dimethyl sulfide (CH3)2S= waste product of plants and bacteria
-effects of deposits found in ancient glacial ice in remote globe areas

Natural sources

-princip. Volcanoes and biological process that occur on land, and water bodies
-major biological source of sulfur= dimethyl sulfide (CH3)2S= waste product of plants and bacteria
-effects of deposits found in ancient glacial ice in remote globe areas

Human activity

-princi. Cause= sulfur and nitrogen
-EX electrici generation. Factories and motor vehicles, most= coal power plants
-gases carried long distances in atom. Before converted and deposited
-short factory funnels= let out smoke
-longer funnels= pollutants carried farther

acid rain definition?

Rain or any other form of precipitation that is unusually acidic,

State and explain pH of "clean rain"

It is slightly acidic, it's pH being about 5.6 because of CO2 and water in air react together.

Name 2 chemical pollutants and acids they form in water that add extra acidity to rain

Extra acidity of rain come from reaction of mostly sulfur oxides and nitrogen oxides (primary air pollutants)with water in the air to form strong acids Iike sulfuric and nitric acids

List AND describe all adverse effects of acid rain

Surface waters and aquatic animals: damage touch as fish eggs not hatching and killing adult fish, biodiversity reduced, insects And fish life elimination. One species greatly affected, could affect entire food web/chain-Al ions washed from acidified soil to streams & lakes, damage fish gills=suffocate Soils: some microbes are unable to tolerate and are killed, enzymes are denatured (changed in shape so they can't function) . Hydronitric ions of acid rain mobilize toxins and leach away essential nutrients and minerals. -Al toxic to plants -Buffering capacity=substance ability to resist pH changes, depends on some soil to neutralize acids. More rock=higher capacities, neutralization use up buffering minerals=eventually decreases Forests and other vegetation: stunts plant growth -Soil's buffering capacity=protection, only neutralizes small a little acid=no nutrients to grow properly.- weakens > kills trees-Vulnerable to diseases, strong winds, extreme cold Human health:cause illness and premature death such as cancer and other deadly diseases. Economic Impact-lumber loss-fish stock reduction Other: damage some building materials and historical monuments and gravestones flake and are damaged

Acid rain and acid precipitation differ?

acid precipitation is all kinds of precipitation like rain, dew and hail, while acid rain is only in the liquid form

b. Acid precipitation is sometimes called "wet deposition". Why is this term appropriate?

precipitation is in a wet state technically speaking, it is in a liquid or wet state.

c. Wet & dry deposition differ?

Dry depositions are particles or gases, while wet depositions are rain, dew, hail and snow

3.What conditions does normal rain become acid rain?

Extra acidity is formed when air particles react with pollutants.

4.
what 2 groups of compounds are largely responsible for causing acid rain?

Sulfur dioxide and nitrogen oxides compounds.

What percentage of sulfur dioxide and nitrogen oxide emissions came from transit in 2004?

SO: <3%
NO: 51%
Suggest 2 things that you could do to reduce amount of acid pollutants from transit.
Attaching pollution controlling tech to reverse NO release

Which aquatic animals are most tolerant of acidic conditions?

water birds, other large organisms, Frogs
Which animals are most affected by acidic conditions?
fish, other small organisms snails

b. Why is calcium oxide capable of neutralizing acids despite not having hydroxide ion in its formula.

The product contains hydroxide, therefore it acts as a base.

c. Explain why adding calcium oxide (lime) to acid polluted lakes only solves problem for a short term.

It is not strong enough to neutralize the acid.

Explain why limestone has higher pH than granite lake.

Limestone does not neutralize acid as well as granite does. The bonded calcium carbonate has more calcium ions that granite, thus does not neutralize as well.

Which is more likely to have healthier aquatic system? Explain.

The granite, it is not as acidic.

Chemical equation how one of these compounds react acid precipitation?

S+ O2=SO2c3NO2 (g)+H2O(l)->2HNO3 (aq) + NO (g)

CaO + water-> calcium hydroxide. Write chemical equation for reaction

CaO+H2O-> Ca(OH)2

Explain why aluminum production produces sludge with such basic pH.

When producing aluminum, the first three minerals are removed using a procedure that relies on corrosive sodium hydroxide, which is a highly basic compound.

How was sludge treated? Explain how this works and what it would produce.

Hundreds of tonnes of plaster and acetic acid were powered into rivers to neutralize the alkalinity. Thus, the cone extraction of toxic metals dropped to potable water levels.

What is more at risk, the Danube, or the surrounding land? Explain.

The surrounding land because the Danube is a very large river with a very high volume of water, while the soil will take a few years to be diluted.

.Explain what is meant by "It helps that the Danube is a large river with a very high volume of water"

Because the Danube is so large, with so much water, over time the content will be diluted.

What pH is "safe" and "normal"?

Neutral 7 of water.

What was pH value at its worst?

9.65

Products of neutralization

pH closer to 7 (neutral) than it was for either reactants
-Potassium hydroxide (KOH) neutralized by cola (slightly acidic)

Chemical Spills

-caustic soda (sulfuric acid + sodium hydroxide) most widely used industrial chemicals
-CAO (lime) slightly upstream

Antacids

-stomach digestion=hydrochloric acid
-pH 1.5
-acid may irritate stomach lining=discomfort & pain
-antacids neutralize =active hydroxide and carbonate compounds
-milk of magnesia=typical antacid containing mgoH (base)
-thick paste not very water soluble=low concentration of OH ions=no chemical burn
-powdered antacids contain baking soda (sodium hydrogen carbonate) as active ingredient

-acid + carbonate base=not simple double displacement =no writing equation

neutralization

where acid + base
-products Always water & salt (ionic compound)
-Subset of double displacement=any product from acid based reaction, not always tille
-In general: acid + base=water + salt

SALT

ionic compound from water metal cation from base + nonmetal from acid

Acids

-b/c H atoms, acids ACT like ionic compounds
-covalent & will separate into ions, liberating H ions when dissolved in H2O
-One characteristic of acids=ability to conduct electricity
-free ions presence=allows electrons to flow
-evidence supporting idea acids dissociate into individual ions in solution

-Common reactions

-...+H2
=metal, loner=won't react with cation series
-CO2 (carbonic acid) will instantly decompose when produced in reaction, "POP"

Bases

-compounds will release OH ions ONLY when dissolved in water
-1 characteristic shared between acids & bases= ability to conduct electricity
-"free ions" presence=allows electrons to flow

-sodium hydroxide

drain cleaner

-aluminum hydroxide

Antacids & water purification gel

-magnesium hydroxide

rolaids= 1 of active ingredients

-potassium hydroxide

cosmetics, & soft/liquid soaps

pH scale

represents acidity or basicity of a solution, measure of how strong base/acid is
-Scale ranges from 0-14
-Neutral solution (ie. pure water)=pH 7
-H & OH concentrations are equal
-Healthy surface skin slightly acidic with pH 5.5
-Solutions highly basic or highly acidic =corrosive and reactive

Acids

0-7 pH value
-Lower pH=more acidic
-acids form ion in solution
-concentration of H ions determines solution's pH
-solutions with highest H ion concentration near "0"
-Greater H concentration in solution=stronger acidic properties

basic solution

-7-14
-Higher pH=more basic
-OH concentration
->7 =higher concentration of OH ions>H ions
-solutions with basic properties (ie drain cleaners) near "14"

pH And Soil

-sensitive soil pH
-Diff. plants grow best in diff. soil acidity conditions
-pH altered by improving growing conditions
-organisms sensitive to small pH changes in environment

all acids release min of _ H ion when water dissolved

1

Binary Acids

-TYpically identify by H atom in front of formula
-EX. HCl (aq)
-H ions give acids their properties
-begins with H, followed by aq
-shows properties only when water dissolved
-Ex. HCl inhaled=water dissolved in throat & lungs=highly corrosive hydrochloric acid

NOT ALWAYS CASE
-binary compound with H atom to be "acid" must dissolve in water
-identify by (aq)=aqueous, dissolved in water

Naming Rules: Binary Acids

name non metal, change ending -> "ic acid"
-Ex. bromic acid
b/c this acid type must be water dissolved, add "hydro
-Ex. hydrobromic acid

*No Names in capitals
*if compound has H atom, no (aq)=typical binary covalent molecule
Formulas: Binary Acids
prefix "hydro"=binary
No space, write symbols for H and nonmetal + charges in top right corner
"Cross Over" charges
*Include (aq)
*No "1"
*reduce
*aq

Oxyacids

-Polyatomic ions related
-formulas differ only by 1/1+ H ions
-identify by H atom at beginning & O atom at end
-Ex. H2SO4 (sulfuric acid)

-NO (AQ) AT END OF FORMULA
-not required
-still an acid

Naming Rules: Oxyacids

identified as oxyacid, name non metal (in mid) but change to "ic acid" ending
*no other additions needed

#H atoms

value of charge of it related polyatomic ion
-EX. phosphate ion, PO43-, has ionic charge of -3= H3PO4

Hydroxides

"OH" ending
-ions made up of 1 O atom (2- charge)
-1 H atom (1+ charge)
=overall charge on hydroxide ion of 1-

Ammonia

NH3
-H = +
-N= -
-why?=not to confuse so ammonia is not thought as acid

Bases Types

-Hydroxides
-Ammonia

Writing Chemical Formulas

-EX. calcium hydroxide
"hydroxide" ending=base
No space, metal symbol, charge as a superscript in top right corner & hydroxide ion, & charge as superscript in top R corner
Ex. Ca2+OH1-
3. "crossover"
-Notes: Hydroxide ion= 1 item, subscript from metal must be counted for entire ion
-Brackets around hydroxide ion (ONLY IF NEEDED)
-ex. +1 Ion needed
-EX. CA (OH)2

Acids

Ion present in solution
[H]+
Reactivity with metals
Product=H2
Electrical Conductivity
Yes
-No ions
-collisions with water molecules break acid molecules apart=cations (H ions) & anions
Taste
Sour
Feel
N/A
pH range
pH<7
Ex. of common households contain an acid or base
batteries, grapefruit, limes, lemons, vinegar
Ex. of chemical formulas and names for acids and bases
HCl(aq), H2S4(aq)
=Aqueous solution
=Sour taste
=substances that react w. metals & carbonates
=conduct electricity
=turns blue litmus red
=neutralize bases
=Food preservative

Bases

Ion present in solution
[OH]-
Reactivity with metals
N/A
Electrical Conductivity
YES
-electrolytes=solutions good conductors of electricity


Taste
Bitter
Feel
Slippery
pH range
pH>7
Ex. of common households contain an acid or base
drain cleaner, soaps, detergents
Ex. of chemical formulas and names for acids and bases
NaOH, CaOH, NaHCO3
=Conduct electricity
=feel slippery
=taste bitter
=Ionic compounds
-as water dissolved= ions released
=Many hydroxides
=In aqueous solutions
-conduct electricity
-Change colours of acid base indicators
-turns red litmus blue
Acid base indicators= shows solution is acidic or basic
-Phenolphthalein=
-acid=colourless
-base=pink

Acids reaction with...

-Metals=H2
-Carbonates
=bubbles of carbon dioxide gas
-Ex. Vinegar & baking soda to unblock a sink

-properties

like adjective: describes what substance is like

-chemical

substance description of what substance does as it forms 1 or + diff. substances

-physical

substance description that does not involve forming new substance -Ex. colour, texture, density, smell, solubility, taste, melting point & physical state

Changes

like verb: describes what substance is doing

chemical changes

substances changes into 1 or + diff. substances
-Products diff. from starting materials

Chemical Changes clues

-Generally irreversible (excep. ex=rechargeable batteries)
-new colour appears
-solid material (precipitation) forms in liquid
-heat/light produced/absorbed
-gas bubbles forme

physical changes

substance remains same substance but changes physical properties in some way
-EX. changes of state (melting, evaporation, condensation, sublimation, dissolving), many reversible

hydrogen

some properties in common with first column metals
-lacks many characteristic physical properties of metals at room temp.

-period

row of elements

-group

column of elements with similar properties

-1

alkali metals: soft, highly reactive

-2

alkaline earth metals: light, reactive

-17

halogens: one of most reactive groups

-18

Noble gases:so stable they rarely react with others

-Nucleus

most of atom's mass concentration in small, dense, positive core

-Atomic number

number of protons in nucleus

-arrangement

order of increasing atomic number

-atoms

electrically neutral, equal number of protons & electrons

-

model representing arrangement of electrons in orbits around nucleus

-Rings

2, 8, 8,

-all atoms

electrically neutral, tot. number of electrons in orbits must = number of protons

-Compounds

pure substance of 2 or + elements in fixed ratio

-VE ring

reactivity

-full VE

stable

-Anions

electrons>protons= - charge. +ide

-Cations

protons>electrons= + charge

Ions

charged particle from atoms that have gained/lost electrons. Many have complete outer orbits =stable
-some in app. concentrations=necessary for health

Making Ionic Compounds From Elements

-Elements (metal + non metal) can react=ionic compound
-metals lose electrons=cations
-b/c metal's hold on VE=weak
=non metals gain electrons=anions
+non metal attracts metal's electrons strongly
=all ions have sam stable, filled VE
-aft. + &- ions from diff. elements attract each other=compounds
-ionic compounds=1&+ metal cations and 1&+ anions
-ionic bond=simultaneous strong attraction of + & - ions in ionic compound

In Ionic Compounds...

-In reaction non metal atoms pull electrons away from metal atoms
-Metal ions:non metal ions (ratio) depends on number of electrons each ion gains/losses
-alternating
-No individual compound particle: always consists of many metal & non metal ions
-Some water soluable
-dissolve=ion separation
-water molecules surround each ion
+molecules arrange so O atoms attracted to cations & H atoms to anions
=no rejoining

Properties

-Most have high melting points
-hard brittle electrolytes: dissolve in water=solutions that conduct electricity
-Most form 3D crystals with many of each kind of ion in fixed ratio held together by opposite charges
-Hard as solids
-Does not conduct as solid
-these ions improves conductivity of water
-pure water=poor conductor
-tap,lake & sea water contain ions from diff. sources (ie. minerals
-maybe solutions only if ions are free to move

electrolyte

compound that separates into ions when dissolved in water (molecules pulled apart)=solution that conducts electricity

- Lose electron

+ charge

-Gain electron

-charge

Naming Rules-Binary Ionic Compounds MONOVALENT

number of each ion must balance + & - charges so that overall charge=0
Electrons from metal to non metals
Charged ions attract ooply charged ions until balanc=Neutral.
Ion numbers must be simplest ratio
No subscript "1"
Super to subscript
2 elements w. charges & same sign will not bond

Subscript

Number of ions needed for Neutral compound

Subscripts

Not charges=no + or -

-Binary

2 diff elements

-Ionic

Metal & Non/charged atom

-Compound

Chem combo of elements

Ionic Bond

Bond involving transfer of electrons from 1 atom to another=ion