Chem Basic Review

Summer Review

Base units

length: meter

mass: gram

volume: liter

time: second

temperature: celcius

Kilo compared to base unit

1000x larger

1x10^3

abbreviation, k

Centi compared to base unit

100x smaller

1x10^-2

abbreviation, c

milli compared to base unit

1000x smaller

1x10^-3

abbreviation, m

micro compared to base unit

1,000,000x smaller

1x10^-6

abbreviation, Greek letter mu

nano compared to base unit

1,000,000,000x smaller

1x10^-9

abbreviation, n

Sig fig rules

• All non-zero digits are significant

• When writing a number in scientific notation, only digits in decimal portion are significant

• Captive zeros (zero between nonzeros) are significant

• Leading zeros (to the left of nonzeros) aren’t significant

• Trailing zeros (to the right of nonzeros) are significant

When doing multiplication/division with sig figs…

Round to the fewest number of sig figs

3\.951 x 0.710 x 21.9837645 = 61.66907601 = 61.1 (3 sig figs)

When doing addition/subtraction with sig figs…

Round to the lowest common decimal place

21\.9837645 + 3.951 + 0.710 = 26.447645 = 26.644 (common in 1000th place)

How to write names of ionic compounds from ionic formulas

Ex: Sn(NO₃)₂

1. Determine the formulas and charges of the ions, write the cation first.

   1. Tin is cation so it could be +2 or +4, nitrate is anion, charge is -1

2. Use subscripts to find total positive and negative charges

   1. Total negative charge= -1 since 2 nitrates. So positive is +2

3. Find name of ions

   1. Tin 2 and nitrate

4. Write name of compound, cation is always first

   1. Tin 2 nitrate

How to write ionic formulas from compound names

Ex: Aluminum sulfate

1. The name gives you the 2 ions, find formula and charges

   1. Alumininum =Al³⁺ and Sulfate=SO₄²⁻

2. Decide how many of each ion is needed to neutralize charge

   1. 2 Aluminums and 3 Sulfates

3. Write formula using subscript and parenthesis

   1. Al₂(SO₄)₃

Notes about formula and nomenclature of ionics

• No charges are written in final formula

• Cation is first

• Parenthesis aren’t used on monatomic ions

• Parenthesis aren’t used on polyatomic ions if there’s only 1

• Parenthesis only used if there’s more than 1 polyatomic ion

Binary inorganics

• Similar to naming ionics, say the name of the first element and the second element is named by adding “ide” to the root

• Use Greek prefixes to denote number of atoms of each element

  • Don’t use “mono” for first element

Prefixes used in naming inorganic molecular compounds

1. mono
2. di
3. tri
4. tetra
5. penta
6. hexa
7. hepta
8. octa
9. nona
10. deca

What are the 7 diatomic molecules

H₂, O₂, N₂, F₂, Br₂, Cl₂, I₂

What is an acid

A substance that yields hydrogen ions (H⁺) when dissolved in water

* Could go by their inorganic name or acidic name depending on its state

What is an oxoacid

Acids that contain hydrogen, oxygen, and another element

ide

hydro…ic acid

Hypo…ite

hypo…ous acid

ite

…ous acid

ate

…ic acid

per…ate

per…ic acid

Hydrocarbons

Only contain carbon and hydrogen

Alkanes

Saturated hydrocarbons contain carbon atoms that each form single bonds

Alkenes and alkynes

Unsaturated hydrocarbons have a double(alkene) or triple(alkyne) bond

* They’re much more reactive than alkanes

How to name organic molecules (alkane, alkene, alkyne)

1. meth…
2. eth…
3. prop…
4. but…
5. pent…
6. hex…
7. hept…
8. oct…
9. non…
10. dec…

How to name isomers (chains)

The longest carbon chain is numbered and the name starts with the number where the bond is

Cyclic hydrocarbons

Carbons arranged in rings, can be alkanes, alkenes, or alkynes

* The prefix “cyclo” is added to the name to indicate it’s a ring

Alcohols

have the hydroxyl functional group (OH)

• Not hydroxide (OH⁻)

• Covalently bonded to a carbon molecule

• Gives polarity to an otherwise nonpolar molecule

• Put ending “OL” onto the name of the hydrocarbon with a number to show which carbon has the OL (similar to double/triple bond)

Ex: Methanol = CH₃OH

Ex: 1 propanol = CH₃CH₂CHOH

Ex: 2 propanol = CH₃CHOHCH₃

Double replacement reactions

Ex: 3 CoCl₂ + 2 Na₃PO₄ →Co₃(PO₄)₂ + 6 NaCl

* 2 ionic reactants, 2 ionic products (cations trade anions)

Single replacement reaction

Ex: 2 HCl + Mg → MgCl₂ + H₂

• 2 products (1 ionic, 1 element), 2 products (1 ionic, 1 element)

• considered a redox reaction

Synthesis reaction

Ex: 2 Mg +O₂ →2MgO

• Multiple reactants (elements or molecules), 1 product

• Often a redox reaction

Decomposition reaction

Ex: 2 H₂O₂ →2H₂O + O₂

• 1 reactant, multiple products

• Often a redox reaction

Combustion reaction

Generic: CxHy + O₂ →CO₂ +H₂O

• 2 CH₃OH + 3 O₂ →2 CO₂ + 4 H₂O

• Something organic (C, H, O?) reacts with O₂, products are CO₂ and H₂O

• Also redox

Redox (oxidation and reduction)

Mg + 2 Ag⁺ →2 Ag + Mg²⁺

Mg + 2 AgNO₃ → 2 Ag + Mg(NO₃)₂

• OILRIG (oxidation is loss, reduction is gain)

• Any reaction that involves the movement of electrons