1. Quarter II Part I: Stoichiometry
Chemistry Study Guide
Quarter II
Part I: Stoichiometry

2. Sample Question I
Elements from which two groups in the periodic table would most likely
combine with each other to form an ionic compound?
From: Virginia End-of-Course Assessments, 2001 Chemistry
A 1 and 2
B 1 and 17
C 16 and 17
D 17 and 18

3. Sample Question II What is the approximate mass of one mole of CO2?
From: 2008 Virginia End-of-Course Assessments, Chemistry
A 24 g
B 44 g
C 28 g
D 56 g

4. Sample Question III
A student calculated the molar mass of Ca(OH)2 as follows:
The answer he calculated is wrong. Which labeled step contains his mistake?
A. Step 1
B. Step 2
C. Step 3
D. Step 4

5. Sample Question IV In chemical compounds, covalent bonds form when —
From: 2003 Virginia End-of-Course Assessments, Chemistry
A the electronegativity difference between two atoms is very large
B electrons are completely transferred between two metals
C pairs of electrons are shared between two nonmetal atoms
D two nonmetal ions are attracted to each other by opposite charges

6. Sample Question V
If the diagram below was the correct representation for the Lewis structure
of a molecule, then the X would be representative of the element —
From: 2003 Virginia End of Course Assessments, Chemistry
A Oxygen
C Nitrogen
B Fluorine
D Potassium

7. Sample Question VI
The sample below contains approximately 9.03 x 1023 atoms of Carbon. The sample most likely contains…
A. 1 mole of Carbon
B. 1.5 moles of Carbon
C. 1 molecule of Carbon
D x 1023 molecules of C

8. Sample Question VII
A student was asked to calculate for the approximate number of molecules that can be expected from a 40-gram sample of glucose. Her calculations are found below.
Her teacher informed her that she made an error. Which labeled step contains the error?
A. Step B. Step C. Step D. Step 4

9. Sample Question VIII The structural formula of methane is shown below:
From the elements making up the compound, this molecule is most likely…
A. crystalline
B. ionic
C. covalent
D. highly polar

10. Sample Question IX
A compound has the empirical formula CH2O and a gram-formula mass of 60 grams per mole. What is the molecular formula of this compound?
From: 2009 Aug NY Regents (Chemistry)
A) CH2O
B) C2H4O2
C) C3H8O
D ) C4H8O4

11. Sample Question No. X The mass of one atom of Potassium is...
A) 1.54 x 1022 g
B) 6.49 x g
C) 3.15 x g
D) 1.14 x 1022 g

12. Sample Question XI
Which atom in the ground state has the most stable valence electron configuration?
From: 2009 June NY Regents (Chemistry)
A) K
B) Si
C) Sc
D) Kr