Chapter 3 Flashcards
What are ionic bonds?
Ionic compound
Bonds that occur between metals and non metals
Involves transfer of electrons from one atom to another
Tightly compacted atoms
What are covalent bonds? (Molecular compound)
Bonds that occur between two or more non metals
Involve the sharing of electrons between two atoms
Freely moving atoms
What are metals and non metals tendencies to lose/gain electrons?
Metals lose electrons (cation)
Nonmetals gain electrons (anion)
Ionic bonds vs Covalent bonds?
Ionic Bond- oppositely charges ions attracted to one another
Covalent bonds- nonmetal+nonmetal - molecular compounds
Which elements come first in a chemical formula?
More metallic (more positively charged) elements first
Which type of formula communicates the most info and which communicates the least?
Most info- structural formula
Least info- empirical formula
What are atomic elements vs molecular elements?
Atomic- elements that exist in nature with single atoms as their basic units (most elements)
Molecular- elements that exist as molecules- two or more atoms of the element bonded together (magic 7 elements are diatomic, 3 inside the 7 are pilyatomic)
How does phosphorus and sulfur exist as states?
P4
S8
What is a polyatomic ion?
An ion composed of two or more atoms
ClO-
CO3
What are binary compounds and how do you name them?
They contain only two different elements
Name of cation + base name of anion-ide
KCl
Potassium chloride
How do you name binary ionic compounds containing a metal that forms more than one kind of cation?
Ex: Fe2+ or Fe 3+
Name of cation (metal) (charge of cation in Roman numerals) + base name of anion (nonmetal) + ide
When using oxyanions, when do we use the ending ate and ite?
The one with more oxygens is given ate
The one with fewer oxygens is given ite
NO3 Nitrate
NO2 Nitrite
What are the ionic compounds called hydrates?
They contain a specific number of water molecules with each formula unit
MgSO4 • 7 H2O
Magnesium Sulfate heptahydrate
What does anhydrous mean?
Mean without the associated water molecules in a hydrate (usually due to heating)
What are the prefixes from 1/2-10
Hemi= 1/2 Mono Di Tri Tetra Penta Hexa Hepta Octa Nona Deca
How do you name molecular compounds?
Prefix + name of first element + prefix + name of second element + ide
Which elements goes forst in a molecular compound when writing it?
The more metal like one
Toward left and bottom of periodic table
What are acids and how do we classify them?
They are molecular compounds that release hydrogen ions when dissolved in water
Binary acids- composed of hydrogen and a non metal
Oxyacids- contain hydrogen and an oxy acids
How to name binary acids?
Hydro + base name of nonmetal + acid
How to name oxyacids?
Ending with ate- base name of oxyanion + ic + acid
Ending with ite- base name of oxyanion + ous + acid
What is the formula mass?
The molar mass
How do we find the mass percent composition of an element?
Mass percent of element X = molar mass of element X times (number of element X’s in the compound) / the molar mass of the compound
Then multiply that all by 100
How many mols of Cl atoms are in CCl2F2?
2 mol of Cl atoms
1 mol CCl2F2 : 2 mol Cl
When given the mass of a compound and asked to find the mass of a given element in that compound how do we solve it?
Mass compound -> moles compound -> moles element -> mass element
How do we find the empirical formula given the mass of two elements?
Take the masses and convert the elements to moles then take the least amount of moles and divide both moles by that and you now have a ratio for the elements
When given the percent mass of each element of a compound and asked to find the empirical formula what do you do?
Pretend the compound it a 100g sample and each percent is grams of the sample then use that data to find the moles
How do you find n ( the number to multiply all the subscripts in an empirical formula to find the molecular formula)
N= molar mass/ empirical molar mass
How do you find an empirical formula using combustion analysis?
Use the given masses of the combustion products and mass of sample to convert mass of CO2 and H2O to moles then convert those moles to moles of C and H and if the compound contains any other elements besides H and C subtract H and C from it to find the mass of it
What is a combustion reaction?
A particular type of reaction in which a substance combines with oxygen to form one or more oxygen- containing compounds
Also emits heat
Ends with CO2 and H2O
