Unit 7- Naming, formulas, and chemical reactions Flashcards
(41 cards)
Rule of zero
In ionic compounds, the positive charge of the metal and the negative charge of the nonmetal cancel each other out
Molecular Formula
Shows the specific number of atoms in a molecule
Empirical formula
Shows the simplest (smallest) whole number ratio of atoms in a molecule
Ionic bond
Forms between a metal and nonmetal
- there is complete electron transfer
- END is greater than 1.69
Covalent bond
Formed between two nonmetals
- shared electrons
- END between 0-1.69
- nonpolar (0-0.3) vs polar (0.3-1.69) covalent
— describes the strength of pull from each atom
Coefficient
Shows number of molecules
Subscript
shows number of atoms
Binary compound
Made from TWO elements
Polyatomic ions
Group of charged atoms
Ternary compound
Made from THREE elements
Crisscross method
Look up the charges of the atoms
Cross over to find subscripts
Put in empirical formula
Check rule of zero
Naming Ionic Compounds
Write the name of METAL first
Write the name of NONMETAL and add “ide”
*if metal has more than one charge, write the specific charge using Roman numerals
Naming Covalent Compoynds
Write the name of the FIRST element
** if first element has subscript of 2 or more, add appropriate prefix
Write the name of the SECOND element and add “ide”
** add prefix (including if there is only one element)
Covalent compound subscripts with prefixes
Mono = 1 Di = 2 Tri = 3 Tetra = 4 Penta = 5 Hexa = 6 Hepta = 7 Octa = 8 Nona = 9 Deca = 10
Charge of Transition Metals in Compound
Determine charge of NONMETAL first
Then choose charge for transition metal that satisfies rule of zero (charges cancel out)
Physical Reaction
The way atoms are arranged doesn’t change *changes are only intermolecular (between molecules- not atoms)
— reactants are not converted into different products
Chemical reaction
The way atoms are arranged changes (intramolecular)
— break ionic and covalent bonds
Determinants of Chemical Reaction
Release of heat and light (exothermic) Absorbing heat (endothermic) Production of gas (bubbles) Formation of precipitate (solid) Change of color **not indicators**
Parts of chemical reaction
Products= substances you end up with Reactants= substances you start with
Law of Conservation of Mass
Mass can’t be created or destroyed in a chemical reaction
— the mass of the reactants= mass of products
Symbols in Chemical Reactions
Arrow: separates reactants from products
+ = “and”
(S)= solid
(G)= gas
(L)= liquid
(Aq)= dissolved solid in solution
Double arrow: reversible reaction
Any symbol above arrow: needed for reaction
Element above arrow: catalyst needed for reaction
Catalyst
Substance (enzyme) that speeds up the rate of reaction
Ways to describe a chemical reaction
Sentence: copper reacts with chlorine to form copper (II) chloride
Word equation: copper + chlorine —> copper (II) chloride
Formula equation: Cu + Cl(2) —> CuCl(2)
Name for NH(3)
Ammonia