CHM 151 Exam 1 UPDATED QUESTIONS
AND CORRECT ANSWERS
How to find mass % from molecular formula - CORRECT ANSWER (subscript of
element x MM of element)/ (MM of compound)
how to find empirical formula - CORRECT ANSWER Start with the number of grams
of each element, given in the problem.
Convert the mass of each element to moles using the molar mass from the periodic table.
Divide each mole value by the smallest number of moles calculated.
Round to the nearest whole number.
how to find molecular formula from empirical formula - CORRECT ANSWER N=
(molecular MM)/empirical MM
naming ionic compounds - CORRECT ANSWER cation (charge if needed) anion-ide
naming covalent compounds - CORRECT ANSWER add prefixes to elements and add
-ide to the end of the anion
Covalent prefixes - CORRECT ANSWER 1-mono
2-di
3-tri
4-tetra
5-penta
6-hexa
7-hepta
8-octa
9-nona
10-deca
AND CORRECT ANSWERS
How to find mass % from molecular formula - CORRECT ANSWER (subscript of
element x MM of element)/ (MM of compound)
how to find empirical formula - CORRECT ANSWER Start with the number of grams
of each element, given in the problem.
Convert the mass of each element to moles using the molar mass from the periodic table.
Divide each mole value by the smallest number of moles calculated.
Round to the nearest whole number.
how to find molecular formula from empirical formula - CORRECT ANSWER N=
(molecular MM)/empirical MM
naming ionic compounds - CORRECT ANSWER cation (charge if needed) anion-ide
naming covalent compounds - CORRECT ANSWER add prefixes to elements and add
-ide to the end of the anion
Covalent prefixes - CORRECT ANSWER 1-mono
2-di
3-tri
4-tetra
5-penta
6-hexa
7-hepta
8-octa
9-nona
10-deca
