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

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

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

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

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

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

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. 6.022 x 1023 molecules of C

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 1 B. Step 2 C. Step 3 D. Step 4

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

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

Sample Question No. X The mass of one atom of Potassium is... A) 1.54 x 1022 g B) 6.49 x 10-23 g C) 3.15 x 10-23 g D) 1.14 x 1022 g

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