BC Science 10 unit 2 Review

8/10/2019 BC Science 10 unit 2 Review

1/16

The CHARGE of an ATOM = 0

# Protons (+) = # Electrons (-)

4.1 Atomic Theory and Bonding

Atom Compound

Composed ofProtons, Neutrons,and Electrons

Different atoms arecalled elements

A pure substancemade up of TWO or

MORE ELEMENTS

NaCl is a compound

O2 is NOT a compound

+

++

Electrons: 1- charge

Protons: 1+ charge

Neutrons: NO charge

ATOMIC # = # of Protons

The mass of an atom= # PROTONS + # NEUTRONS(electrons have almost no mass)

PROTONS + NEUTRONS + ELECTRONS

= SUBATOMIC PARTICLES

+

METALS SEMI-

METALS

NON-METALS

ATOMIC MASS =#Protons + #Neutrons

Charge when an ion.*Atom has no charge

ATOMIC # =# Protons

* Atomic Mass should be rounded to nearest wholenumber EXCEPT when dealing with isotopes


2/16

Bohr Diagrams

Electrons and Periods

Forming Compounds

Ionic Compounds

Valence Shell Rule: 2:8:8 RULE

Electrons are organized in shells:

1st Shell: MAX 2 electrons2nd Shell: MAX 8 electrons

3rd

Shell: MAX 8 electrons

As you move RIGHT, ONEMORE ELECTRON is added,until the outer SHELL is FULL(In this case 8 on outer shell)

Period or ROW Far right column in this rowhas FULL SHELL, called aSTABLE OCTET

Outer shell is calledthe VALENCE SHELL

There are 2 types of compounds:

1. Ionic 2. Covalent

Formed from + and charged ions Involve TRANSFER of ELECTRONS Held together by IONIC BONDS

Formed when 2 elements SHAREelectrons

There are no IONS formed Held together by COVALENT BONDS

Ionic compounds form from IONS:METAL ATOMS lose ELECTRONS to form a POSITIVE ION (CATION)NON-METAL ATOMS gain ELECTRONS to form a NEGATIVE ION (ANION)

IONS are ATOMSthat have eitherGAINED or LOST

ELECTRONS

Charge of theion that forms:

-1 for Chlorine

Charge of the ionthat forms:+3 for Aluminum

Metal: Cation (Positive)Non-Metal: Anion (Negative)

Chlorine will GAIN 1 electron to form an ION Aluminum will LOSE 3 electrons to form an ION

Family or COLUMN:#18 Noble Gases: FULL VALENCE SHELL


3/16

Ionic vs Covalent Compounds

Lewis Diagrams

Step 2 : Add any extra

dots as pairs

Some METALS can form MORE THAN ONE ion: called Multivalent

Iron can form either:+3 charge OR +2 charge

NON-METALS ARE NEVERMULTIVALENT

Ionic

Covalent (Molecular)

Sodium has one electronon VALENCE shell. Itwants to lose this

Chlorine needs ONEmore electron on its

Valence shell to make 8.It wants to gain one

1 2

3

SODIUM DONATES1 ELECTRON

CHLORINE ACCEPTS1 ELECTRON

SODIUM IONFORMED +1

CHLRORINE IONFORMED -1

SODIUM CHLORIDE FORMED

Electrons are SHAREDbetween the Nitrogen atomand the 3 Hydrogen atoms

NO electrons areTRANSFERRED

NO IONS are formed

Lewis diagram shows ONLY theVALENCE electrons (outer shell)

Step 1: Draw 4 dots alone first


4/16

Lewis diagrams to show Ions and Ionic Compounds

Lewis Diagram of Covalent Molecules

Naming Simple Ionic Compounds

Ionic Compound Formulas

-Sodium loses its onlyouter valence electron;-Chlorine gains anelectron to fill in its last

pair

FLUORINE ATOM

F

8-

FLUORINE ION

F-

Nitrogen has 5 VALENCEelectrons

Nitrogen SHARES 3electrons with threehydrogen atoms. Thisleaves 2 electrons notpaired to anything

Fluorine has oneunpaired electron.Each Fluorine shares itslone electron with theother lone electron.

4.2 Names and Formulas of Compounds

Ionic compounds: compounds composed of POSITIVE CATIONS and NEGATIVE ANIONS

Ionic compounds are named

using the IUPAC standard of naming:

Sodium Chloride

Metal :

Always comes first Never ends in ide

Non-Metal :

Always comes last

Ends in ide

Na3P

Subscript = # of Na ions in this compound

When no subscript is writtenthe value is 1

Na

Na NaP

Means THREE Naions bind toONE P ion


5/16

Writing Ionic Compound Formulas from Ions (SHORTCUT METHOD)

Multivalent Ions

Writing Formulas from Compound Names with Multi-Valent Ions

Writing Names from Formulas (REVERSE of above)

Polyatomic Ions

Step 1: Write out ions

Mg +2 with N-3

Step 2: Cross Charge #s

Mg +2 with N-3

Step 3: Write newsubscripts

Mg 3N2

Step 4: ReduceSubscripts (if possible)

Mg 3N2

Mn+4 with 0-2 Mn+4 with 0-2 Mn2O4 MnO2

When naming MULTIVALENT IONS you must indicate whichcharge of ion: e.g. Fe +3 would be Iron (III)

In a compound containing Fe +3 you would name this:

Iron (III) Oxide not Iron Oxide

Some METALS can form more than onet e of ion = multi le char es

Vanadium (IV) Oxide

Step 1: Write out ions

V +4 with O-2

Step 2: Cross Charge #s Step 3: Write newsubscripts

Step 4: ReduceSubscripts (if possible)

V +4 with O-2 V 2O4 VO2

VO2 Step 1: Uncross

subscriptsStep 2: Write uncrossed

numbers as charges

Step 3: Fix the NON-METAL ion to its correct

charge

Step 4: Write the namesof the ions in your

Formula Name

VO2 V +2 with O-1 V +4 with O-2 (Oxygen must be doubled;so must Vanadium then)

Vanadium (IV) Oxide

Polyatomic ions are IONS MADE UP OF MORE THAN ONE TYPE OF ATOM:

NO3-

In the formula MgSO 4, to determine if you are dealing with a polyatomic ion look for a normal ionFIRST AND CIRCLE

Mg SO 4 The remaining ion is not simple so it must be a Polyatomic Ion

Made up of :ONE Nitrogen

THREE Oxygens

The entire thing has a TOTAL charge of -1


6/16

Naming Formulas Containing Polyatomic Ions

Covalent Compounds

Al (OH)3 Using methods above, we would see that there is:

Name your compound using ions that it contains: Aluminum Hydroxide

One Aluminum ION Three OH IONS

Reminder that Aluminumdoes not need Roman

Numerals

OH- is not a regular ion so you mustuse the provided POLYATOMIC

Naming sheet to name

Covalent Compounds DO NOT have IONS: Naming is different from Ionic compounds

Naming Rules:

N2O = dinitrogen monoxideP4S10 = tetraphoshphorus decasulfide

CO is NOT monocarbon monoxide:it is carbon monoxide

There is no NO METAL,making this a

COVALENT COMPOUND

DO NOT REDUCE THE SUBSCRIPTS FOR

COVALENT COMPOUNDS

Covalent Compoundsare named accordingto their SUBSCRIPTS

IDE endings are thesame for covalent

EXCEPTION TO THE RULE:

If the FIRST element is a ONE you DO NOT use MONO

Formula Name

CH4 methane

NH3 ammonia

H2 O water

Some COVALENTCOMPOUNDS

HAVE COMMON NAMES:

CS2 P4O10


7/16

Chemical Reaction Structure

Conservation of Mass in Chemical Change

Writing and Balancing Chemical Equations (SIMPLE)

4.3 Chemical Equations

Word Equation: nitrogen monoxide + oxygen nitrogen dioxide

Symbolic Equation: 2NO + O 2 2NO2

Reactants Products

Coefficients are number placed in front of a FORMULA

Conservation of Mass states that mass is conserved in a chemical reaction

TOTAL MASS REACTANTS = TOTAL MASS PRODUCTS

Step 1: Write out Word Equation: Iron + Bromine Iron (III) Bromide

Step 2: Write out Skeleton Equation with ions: Fe + Br 2 Fe+3 + Br-

Step 3: Write out Skeleton Equation: Fe + Br2 FeBr 3

Step 4: Balance the equation by adding 2 Fe + 3 Br2 2 FeBr 3 COEFFICIENTS

2 Irons 2 Irons3 x 2 =6

Bromines

2 x 3 =6

Bromines


8/16

Writing and Balancing Polyatomic Equations

Acids and Bases Core Ideas

Acid BasepH value 0 to less than 7 More than 7 to 14Corrosive? YES YES Taste SOUR BITTERReact with metals? YES NO

pH Indicators

Step 1: Tin(IV) Nitrite + Potassium Phosphate Potassium Nitrite + Tin (IV) Phosphate

Step 2: Sn+4 NO2- + K+ PO4

-3 K+ NO2- + Sn+4 PO4

-3

Step 3: Sn(NO 2)4 + K3PO4 KNO2 + Sn3(PO 4)4

Step 4: 3 Sn(NO 2)4 + K3 PO4 3 K NO2 + Sn3(PO 4)4

Step 5: 3 Sn(NO 2)4 + K3 PO4 3 KNO2 + Sn3(PO 4)4

Step 6: 3 Sn(NO 2)4 + 4 K3 PO4 12 KNO2 + Sn3(PO 4)4

Use SHORT CUT RULE

(SHOWN PREVIOUSLY )

Treat each POLYATOMICION AS A GROUP

Four NO2 One PO4 One NO2 Four PO4

Balance Metals

HINT: When balancing equations with OXYGEN and HYDROGEN,balance the CARBON first, then hydrogen, then oxygen

5.1 Acids and Bases

Acids DONATE H+ ionsBases ACCEPT H+ ions

pH Scale

0 to less than 7 =ACID More than 7 to 14 = BASE

7= NEUTRAL

Phenolphthalein: COLORLESS TO PINK from 8.2-10.0Bromothymol blue: YELLOW TO BLUE from 6.0-7.6

See DATA BOOKLET


9/16

Naming Acids

Naming Bases

Acid versus Bases (In solution)

Core Concepts

Normal : Hydrogen Chlor ide becomes Hydrochlor ic Acid

Special : Hydrogen Carbon ate becomesCarbon ic Acid

Hydrogen Sulf ite becomesSulfur ous Acid

HCl Hydrogen Chloride HCl (aq) Hydrochloric Acid Aqueous (aq)(in solution)

Dry

IDE turns into IC

ATE turns into IC but NO hydro

ITE turns into OUS

Bases are H+ acceptors; usually have an OH on the right side of their formula

Caustic: a solution made from very reactive bases (e.g. concentrated Sodium Hydroxide)

NaOH Sodium HydroxideCa(OH) 2 Calcium HydroxideNH4OH Ammonium Hydroxide

More H+

than OH-

ACIDS H

+

= OH-

NEUTRAL More OH

-than H

+

BASES

Pure water has the same amount of H+ and OH- ions :MEANING there are NO EXTRA H + ions or OH - ions

H+ + OH- H2O

Since ACIDS and BASESproduce IONS

they CONDUCT ELECTRICITY

5.2 Salts

Salt: Contain a positive ion (from a base) and a negative ion (from an acid ) e.g. NaCl

ACID + BASE SALT + WATER Na + OH- H+ Cl-


10/16

Acid/Base Neutralization

Oxides Reacting with water

Acids and Metals

Core Ideas

3 H2SO4 + 2 Al(OH) 3 Al2(SO4)3 + 6 H2O

ACID BASE SALT WATER

Metal Oxides react with water to form a BASE

Non-Metal Oxides react with water to form an ACID SO2(g) + H 2O --> H 2SO3 (aq)

Na 2O(s) + H2 2O --> 2 NaOH (aq)

An oxide is a compound with a METAL or NON-METAL with OXYGEN

Acids will react with METALS to form a SALT and HYDROGEN GAS

Na 2O(s) + H 2O --> 2 NaOH (aq)

2 HCL (aq) + Mg (s) --> MgCl 2 (aq) + H 2 (g)

5.3 Organic Compounds

Organic: Compounds that contain CARBON

Inorganic: Compounds that do NOT contain CARBON (exceptions are: CO 2 + CO + CO3-2 + Carbides)

Carbon has 4electrons in its valence shell

Carbon forms4 COVALENT BONDS

Carbides are IONIC compounds thathave CARBON as a NON-METAL:

e.g. Al 4C3


11/16

Hydrocarbon examples

Alcohol examples

Reaction Types

HYDROCARBONS:Organic compoundthat only contains

CARBON andHYDROGEN

ALCOHOLS:Organic compoundthat only contains

CARBON, HYDROGEN,& OXYGEN

6.1 Types of Chemical Reactions

Synthesis:

Decomposition:

A + B C

2 Na + Cl2 2 NaCl

AB A + B

2 NaCl 2 Na + Cl2

2 Na + Cl2 2 Na+ and 2 Cl -

ATOM ATOM ION ION

2 Na+ and 2 Cl - 2 Na + Cl2ION ION ATOM ATOM


12/16

Single Replacement VS Double Replacement Reactions

Neutralization Reaction Combustion Reaction

2Al + 3CuCl2 3Cu + 2AlCl3 Pb(NO3)2 + 2NaI 2NaNO3 + PbI2 M NM M NM M M

SINGLE REPLACEMENTA METAL CAN SWITCH WITH A METAL

ORA NON-METAL WITH A NON-METAL

Remember:A METAL forms + IONS

NON-METAL forms - IONS

DOUBLE REPLACEMENTION switches with a ION

AND- ION switches with a - ION

ACID + BASE SALT + WATER

H2SO4 + Ca(OH)2 CaSO4 + 2 HOH

H+ + OH- H2O (HOH)

HYDROCARBON + O2 CO2 + H2O

CH4 + 2 O2 CO2 + 2 H2O

SUGARS such as Glucose (C 6H12O6)will also undergo combustion

6.2 Factors Affecting the Rate of Chemical Reactions

Rate of Reaction: How quickly or slowly reactants turn

into products

Every chemical reaction occurs at a certain RATE

4 things AFFECT REACTION RATE: 1. Temperature2. Concentration3. Surface Area

4. Presence of a Catalyst

1. Temperature

Temp = Reaction Rate

2. Concentration

Concentration = Reaction Rate

Increased temp. means an increase in KINETICENERGY = More particles colliding

Increased conc. means that there are moremolecules in a solution to collide with one another


13/16

Core Ideas

Isotopes

3. Surface Area

Surface Area = Reaction Rate

4. Catalysts

Surface area is a measure of how much areaof an object is exposed

The greater the surface area the more of asolid is available to react

A substance that speeds up the rate of a chemicalreaction

Catalysts LOWER the energy needed to breakbonds for a reaction to occur

Catalysts are not used up in a chemical reaction

Biological Catalysts are called ENZYMES

Catalysts allow REACTANTS to better line up andproperly collide making a reaction easier to occur

7.1 Atomic Theory, Isotopes, Radioactive Decay

Radioactivity: release of HIGH ENERGY PARTICLE OR WAVES

Natural Background Radiation: radiation that occurs in our environment. This radiationhas the potential to interact with ATOMS creating IONS

1. Electromagnetic Radiation: (energy waves) RADIO WAVES to GAMMA WAVES

2. High energy particles: ALPHA and BETA PARTICLES

Two types of Radiation

Discovered by Roentgen and later Marie Curie

that uranium caused photographic plates todarken: this led to the discovery of what she

called RADIOACTIVITY

Isotope: the SAME particular element but with a DIFFERENT ATOMIC MASS

Note that the ATOMIC MASSlisted is the AVERAGE mass forALL the K atoms in nature:SOME ARE HEAVIER than 39

but the AVERAGE K weighs

39.1 AMU

POTASSIUM has 3 isotopes:K-39 K-40 K-41 19 P 19 P 19 P

20 N 21 N 22 N

ONLY THE # OF NEUTRONS ISDIFFERENT Some ISOTOPES are RADIOACTIVE and

undergo DECAY


14/16

Radiation Types

Core Ideas

Electromagnetic Radiation

The more frequent(compressed) the energy

waves are the moreENERGY they carry

GAMMA RAYS are highenergy destructive

waves released bycertain radioactive

ATOMS

Radioactive Decay: these include ALPHA and BETA particles

Positively Charged Same as a helium nucleus

Low-penetration

Negatively Charged Same as an electron

Higher-penetration

Alpha Beta

BOTH ARE EJECTED FROM A NUCLEUS DURINGRADIOACTIVE DECAY

MASS is conserved meaningit is the SAME on both SIDES

of ARROW

Bottom #s = CHARGES

NO CHARGE or MASS ARE WAVES not particles HIGHEST-penetration

Gamma

7.2 Half Life

Radiocarbon Dating: determining the age of an object by measuring the amount of Carbon-14 remaining

Half Life: The amount of time it takes for HALF of the nuclei in a sample to decay(THIS IS A CONSTANT)

At start: 100%1 st Half-life 50%2nd Half-life 25%3 rd Half-life 12.5%

The time it TAKES toget to each half life is

specific for eachradioactive atom

Parent Daughter


15/16

Using a Decay Curve

Core Ideas

You can use this graph tofind out HOW much PARENTis left at ANY point in time

(even between half lives)

Remember:

Parent % + Daughter % = 100% Use this scale to read

what % is remaining

Use this scale toread how much

time has passed

7.3 Nuclear Reactions

Nuclear Fission VS Nuclear Fusion The splitting APART of a BIGGERnucleus into 2 SMALLER NUCLEI,

LOTS OF ENERGY, andSUBATOMIC PARTICLES

The fusion of 2 SMALLER NUCLEI(JOIN TOGETHER) to make aBIGGER NUCLEUS, LOTS OFENERGY, and SUBATOMICPARTICLES

FORMS A BIGGER NUCLEI:MUST BE FUSION

FORMS 2 SMALLER NUCLEI:MUST BE FISSION

ENERGY ENERGY

During FISSION a smallerparticle such a NEUTRON (n )may be fired at a the LARGERNUCLEUS to break it apart

Remember, MASS is conserved: This means that the MASS of the LEFT SIDE of the

reaction = MASS of the RIGHT SIDE


16/16

Chain Reaction: One nuclear reaction initiates the next reaction

In Canada, we use CANDU reactors, which are safe yet efficient system to generatingelectricity .HOWEVER, this FISSION reactor produces radioactive waste that must be isolated safely forthousands of years

SUN: The sun is a giant FUSION REACTOR:

Must be controlled:

In a NUCLEAR REACTOR certain materials are used to control therelease of NEUTRON which are the BULLETS that are released by aREACTION and TRIGGER the next reaction(SEE ABOVE)

Scientists are looking for ways to create FUSION nuclear reactorsThese usually produce wastes that are NOT radioactive

Heaver isotopeof Hydrogen:Deuterium

High pressure in the sun FUSES the 2HYDROGEN NUCLEI together

Documents

BC Science 10 unit 2 Review