Name:_________________________ Period:___ Due Date: 1-30-2019

Nomenclature NOTES: Chemistry Rules for naming and writing ions, compounds & formulas: (note that errors in original notes are corrected in red)

What is what?

I. Ions: H+, Na+, N+3, O2-, S2-

II. Chemical Formulas (recipe of a compound): NaCl, H2S, HNO3

III. Chemical Names: Common name and systematic (scientific name): NaCl = sodium chloride, H2S = hydrogen sulfide, HNO3 = Hydrogen nitrate or nitic acid

This unit will teach you how to write chemical formulas and their names based on the charges of mono-atomic and poly-atomic ions and chemistry rules that govern naming (nomenclature).

General rules when writing chemical formulas:

The cation symbol is written fist and the anion symbol follows after If two non-metals make a compound, the most metallic element assumes the Cation role.

(see example #3) If multiple atoms of the same element are present, subscripts are added after the symbol to

indicate number of atoms to balance out oxidation numbers to equal a NET (total) zero charge. Ex: CCl4 = 1 carbon atom and 4 chlorine atoms. Note: no subscript is written for a single atom.

General rules when writing chemical formula names:

The complete ATOM-name of the anion is written first name is written fist followed by the anion ATOM-name ending with “-ide.” Note this is written as 2 words. Example: In the compound, CCl4 chlorine is written as ‘chloride’

Prefixes are used to indicate multiple numbers of atoms that are present in compounds (see Table-4)

Example 1: A compound made by Chlorine and Carbon: FORMULA: CCl4 = Carbon tetrachloride

Oxidation numbers of C and Cl respectively: +4 and -1

Example 2: A compound made by Magnesium and Oxygen: FORMULA: MgO = Magnesium oxide

Oxidation numbers of Mg and O respectively: +2 and -2

Example 3: A compound made by Chlorine and Nitrogen: Since both are non-metals, write the MOST-metallic one first as it will act as a cation in the compound.FORMULA: NCl3 = Nitrogen chloride (or Nitrogen trichloride)

Oxidation numbers of N and Cl respectively: +3 and -1

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1. Naming ions: Compounds can be either Binary or Tertiary. Binary compounds are made of two elements.

Tertiary compounds are made up of more than two elements.

Ex: Binary compounds: NaCl, Al2O3

Tertiary compounds: H2SO4 , NaOH, Li3PO4

Atoms gain or lose electrons to achieve the nearest noble gas electron configuration. When this happens, they become cations or anions. Oxidation number of an atom is the same as its charge that shows how many electrons were gained or lost to obtain noble gas configuration. (Use Chris-cross method. (Ex: MgCl2 = Metal gets a + charge and non-metal gets a – charge. Mg2+ combines with Cl 1-)

In general, METALS make cations and NON_METALS make anions. NOBLE GASES in Group 8A do NOT make ions.

Metals in Group-A (1A, 2A and 3A and some 4A elements) lose electrons they form cations (+ charge) equal to their group number (or number of valence electrons).

The charge of any Group-A non-metal (4A, 5A, 6A, 7A) is determined by subtracting 8 from the group (valence electron) number. They make anions with a negative charge.

Most Polyatomic ions (ions with more than two atoms) have names ending with “-ite” or “-ate”

Table 1: Ionic charges of Representative elements1A 2A 3A 4A 5A 6A 7A 8A

Period 1 H+ n/aPeriod 2 Li+ Be2+ B3+ C+4/-4 N3- O2-

F - n/aPeriod 3 Na+ Mg2+ Al3+ Si+4/-4 P3- S2-

Cl - n/aPeriod 4 K+ Ca2+ Ca3+ As3- Se2-

Br - n/aPeriod 5 Rb+ Sr2+ Sr3+

I - n/aPeriod 6 Cs+ Ba2+ Ba3+ n/a

2. Naming ionic compounds (ionic formulas) The net charge of an ionic compound must be zero. Therefore, the number of cations

and anions in an ionic compound must be balanced to make an electrically neutral compound.

When naming ionic compounds, the cation retains the same name as the element. The anion’s name is similar to the elemental name, but the ending of the name has been removed and replaced with “-ide.”

Transition metals (in the d-block) can make multiple cations and have multiple oxidation numbers. So, the charges are determined by the number of electrons LOST. When a cation has more than one oxidation number :

i. Systematic Name: a ROMAN NUMERAL is placed inside parenthesis and used AFTER the element name to indicate the oxidation state.

ii. Common name (old method): uses the suffixes -ous and -ic to denote the lower and higher charges (oxidation states), respectively.

Table-2: Roman NumeralsRoman Numerals used in naming Molecular compounds

Number 1 2 3 4 5 6 7 8 9 10Roman numeral I II II IV V VI VII VIII IX X

Laws explaining the formation of compounds:

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Law of multiple proportions

Law of definite proportions

Table-3: Systematic and Common names used to describe high and low Cation oxidation states:

Formula Cation oxidation state Systematic name Common nameCuCl +1 Copper(I) chloride Cuprous chlorideCuCl2 +2 Copper(II) chloride Cupric chlorideHg2Cl2 +1 Mercury(I) chloride Mercurous chlorideHgO +2 Mercury(II) chloride Mercuric chlorideFeS +2 Iron(II) sulfide Ferrous sulfideFe2S3 +3 Iron(III) sulfide Ferric sulfide

2. Naming covalent (molecular) compounds: In nomenclature of simple molecular compounds, the more electropositive atom is

written first, and the more electronegative element is written last with an “-ide” suffix.

The Greek prefixes are used to indicate the number of a given element present in a molecular compound.

Common exceptions exist for naming molecular compounds, where trivial or common names are used instead of systematic names, such as ammonia (NH3) instead of nitrogen trihydride or water (H2O) instead of dihydrogen monooxide.

Table-4: Prefixes are used to indicate multiple numbers of atoms that are present in compounds:

Greek Prefixes used in naming BINARY Molecular compoundsPrefix Mono- Di- Tri- Tetra- Penta- Hexa- Hepta- Octa- Nona- Deca-Number 1 2 3 4 5 6 7 8 9 10

Table-5: Symbols and names of metal ions with multiple oxidation states:

Symbol Systematic ion name Common ion name Cu + Copper(I) Cuprous

Cu 2+ Copper(II) Cupric chlorideFe 2+ iron(II) FerrousFe 3+ Iron(III) FerricHg + Mercury(I) Mercurous

*Hg2 2+ Mercury(II) Mercuric Pb 2+ Lead(II) PlumbousPb 4+ Lead(IV) PlumbicSn 2+ Tin(II) StannousSn 4+ Tin(IV) StannicCr 2+ Chromium(II) ChromousCr 3+ Chromium(III) Chromic

Mn 2+ Manganese(II) ManganousMn 3+ Manganese(III) ManganicCo 2+ Cobalt(II) CobaltousCo 3+ Cobalt(III) Cobaltic

*Is a di-atomic ionTable-6: Common polyatomic ions:

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Formula Name Charge/Oxidation state

H2PO4 - Dihydrogen phosphate

1-

C2H3O2- Acetate

HSO3 - Hydrogen sulfite

HSO4 - Hydrogen sulfate

HCO3- Hydrogen carbonate (“bicarbonate)”

NO2- Nitrite

NO3- Nitrate

CN- Cyanide

OH- Hydroxide

MnO4- Permanganate

ClO - Hypochlorite

ClO2 - Chlorite

ClO3 - Chlorate

ClO4 - Perchlorate

HPO42- Hydrogen phosphate

2 -

C2O42- Oxalate

SO32- Sulfite

SO42- Sulfate

CO32- Carbonate

CrO42- Chromate

Cr2O72- Dichromate

SiO32- Silicate

PO33- Phosphite 3 -

PO43- Phosphate

NH4+ Ammonium 1+

Ex: Write the formulas for the following ( Use Table 6):1) Sodium Phosphate =

2) Hydrogen cyanide =

3) Potassium dichromate =

4

4) Ammonium nitrate =

5) Magnesium acetate =

6) Aluminum sulfate =

7) Cobalt(II) oxalate

3.Naming acids

Table-7 Naming common acidsAnion ending Anion/ Anion name Acid name construction Acid name-ide Cl - / Chloride Hydro-(stem)-ic acid Hydrochloric acid-ate NO3

- / Nitrate (stem)-ic acid Nitric acid- ite SO4

2- / Sulfite (stem)-ous acid Sulfurous acid

Acids have the general formula HnX. Acid naming system depends on the anion name which can end with the suffix: -ide, -ite or -ate. When the name of the anion (X) ends with an -ide the acid name begins with the prefix, “hydro-”.

The stem of the anion has the suffix -ic and is followed by the word ‘acid.’Ex: HCl = (X) = chloride => hydrochloric acid

H2S = (X) = sulfide => hydrosulfuric acid When the anion name ends with -ite, the acid name begins with the stem of the anion name

ending with the suffix -ous, followed by the word ‘acid’. When anion name ends with -ate, the acid name begins with the stem of the anion with the

suffix, -ic followed by the word, ‘acid.’ Ex: HNO3 = (X) = Nitrate => Nitric acid

Table 8: Common acid names and formulas

Name FormulaHydrochloric acid HCl

Nitric acid HNO3

Sulfuric acid H2SO4

Acetic acid CH3COOHPhosphoric acid H3PO4

Carbonic acid H2CO3

4. Naming Bases Formula: Cation symbol followed by the hydroxide anion (OH –). Base name: Cation name followed by the word, ‘hydroxide.’

Table 9: Common Base names and formulas:

Name Formula Sodium hydroxide NaOHMagnesium hydroxide Mg(OH)2

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Aluminum hydroxide Al(OH)3

Ammonium hydroxide NH4OH

Summary:

Figure -2: Compound naming Decision Tree

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Figure-2 : Periodic Table Distribution of Metals, Metalloids and Non-Metals:

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Name:________________________ Period:___ Due Date: 1-30-2019 Score: _____/100

Chemical Nomenclature Home work (HW 3) given:1-23-2019

19. What are the oxidation states of the following elements?

a. Sr:_____ b. Ca:____ c. Al:____ d. Sn(IV):____ e. Cu (II):_____

20. Element J makes the following 3 compounds with oxygen. What is the oxidation state of J in each? (a) J2O = ____ (b) JO = _____ (c) J2O3 =________

21. What is the formula and name of a compound made with Iodine and Astatine?________________

22. What is the formula and name of a compound made with Hydrogen and Carbon?_____________

23. In the periodic table where are you likely to find element J?

a. S-block b. d-block c. p-block d. f-block

24. Name the following polyatomic ions:a. SO4

2- ___________________________

b. SO32-

__________________________ c. OH-

__________________________

d. ClO3- __________________________

e. CrO42-

__________________________f. C2H3O3

- _________________________

25. Write the name of the formulas below and Circle those that are binary ionic compounds: a. CaSO4 __________________ b. Na2S _________________ c. H3PO4 _______________

d. Al2O3 ________________e. K2CrO4 _________________f. CCl4 __________________

26. Write the molecular formulas of the following compounds:a. Magnesium phosphate:________b. Sodium bromide:_____________c. Stannic oxide________________d. Lead(II) carbonate____________

e. Calcium hydroxide______________f. Silver nitrate____________________g. Strontium bicarbonate___________h. Vanadium pentoxide ___________

Name:________________________ Period:___ Due Date: 1-30-2019 Score: _____/50 (formative)

Q3 LAB1: Topic: Chemical bonds & Nomenclature LAB

Pre-lab Questions:1. What happens to ionic and Molecular (covalent) compounds when they are dissolved in water?

Discuss with your lab group and decide on best answer. Then write it below:

2. Determine the Formula of the following Polyatomic compounds using the Chris-cross method:i. Magnesium nitrate

ii. Copper sulfate

iii. Aluminum silicate

iv. Hydrobromic acid

3. Resonance structures: Resonance structures are a set of two or more Lewis Structures that collectively

describe the (electron) bonding of a single polyatomic molecule including fractional bonds and fractional charges.

Resonance structure are capable of describing delocalized electrons that cannot be expressed by a single Lewis formula with an integer number of covalent bonds.

Chemistry LAB ACTIVITY: In your groups Plan and construct the following Molecules or ions and draw their structures using the items provided:

Use the following playdoh colors and ITEMS to make atoms:Hydrogen (H) = GREENCarbon (C) = YellowOxygen (O) = Bright purple

*Use remaining colors for the other atomsBonds = Toothpicks

Compound Structure (use lines and chemical symbols

Systematic Name

1 HCl

2 CH4

3 C3H8

4 C3H7Cl Draw ALL possible structures

5 NH4Cl

6 Calcium hydroxide

7 Copper(I) oxide

8 H2SO4