3.3 Representing Compound: Chemical Formulas and Molecular Models Flashcards
The quickest and easiest way to represent a compound is with its ______ ______ , which indicates the elements present in the compound and the relative number of atoms or ions of each.
The quickest and easiest way to represent a compound is with its chemical formula , which indicates the elements present in the compound and the relative number of atoms or ions of each.
The formula contains the ______ for each element and a ______ indicating the relative number of ______ of the element.
The formula contains the symbol for each element and a subscript indicating the relative number of atoms of the element.
Chemical formulas normally list the more ______ (or more positively charged) elements first, followed by the less ______ (or more negatively charged) elements.
Chemical formulas normally list the more metallic (or more positively charged) elements first, followed by the less metallic (or more negatively charged) elements.
Chemical formulas can generally be categorized into three different types: ______, ______, and ______.
Chemical formulas can generally be categorized into three different types: empirical, molecular, and structural.
An ______ ______ gives the relative number of atoms of each element in a compound.
An empirical formula gives the relative number of atoms of each element in a compound.
A ______ ______ gives the actual number of atoms of each element in a ________ of a compound.
A molecular formula gives the actual number of atoms of each element in a molecule of a compound.
the empirical formula for hydrogen peroxide is HO, but its molecular formula is _____.
the empirical formula for hydrogen peroxide is HO, but its molecular formula is H2O2 .
The ______ ______ is always a whole-number multiple of the empirical formula
The molecular formula is always a whole-number multiple of the empirical formula
A structural formula uses lines to represent ______ ______ and shows how atoms in a molecule are connected or bonded to each other.
A structural formula uses lines to represent covalent bonds and shows how atoms in a molecule are connected or bonded to each other.
The type of formula we use depends on how much we know about the compound and how much we want to ______ . A ______ ______ communicates the most information, while an ______
______ communicates the least.
Conceptual
The type of formula we use depends on how much we know about the compound and how much we want to communicate. A structural formula communicates the most information, while an empirical formula communicates the least.
Conceptual
Write empirical formulas for the compounds represented by the molecular formulas.
(a) C4H8
For C4H8, the greatest common factor is 4. The empirical formula is therefore CH2 .
Write empirical formulas for the compounds represented by the molecular formulas.
(b) B2H6
For B2H6, the greatest common factor is 2. The empirical formula is therefore BH3 .
Write empirical formulas for the compounds represented by the molecular formulas.
(c) CCl4
For CCl4 , the only common factor is 1, so the empirical formula and the molecular formula are identical.
To determine the empirical formula from a molecular formula, divide the subscripts bythe ______ ______ (the largest number that divides exactly into all of the subscripts).
To determine the empirical formula from a molecular formula, divide the subscripts bythe greatest common factor (the largest number that divides exactly into all of the subscripts).
A ______ ______ is a more accurate and complete way to specify a compound.
A molecular model is a more accurate and complete way to specify a compound.
