University:
Kentucky State University
Course:
CHE 101 | General Chemistry I
Academic year:

2021
Views:

464

Pages:

3
Author:

Athena Harrison

**Department of Chemistry** **General Chemistry, Chem. 101** **First Exam** **#3** **Name:** **Student ID No.:** **Lecture time:** **Instructor:** **Serial No.:** **Periodic Table** [Image of the periodic table with elements and atomic numbers] **Useful Information** * °F = (9/5)°C + 32 * °C = (°F - 32) * 5/9 * 1 mile = 5280 feet * 1 foot = 12 inches * 1 inch = 2.54 cm * 1 pound (lb) = 453.59237 g * Avogadro's number = 6.022 x 10^23 **Choose the correct answer and put your choices in the suitable places in the table below.** | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | |---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---| | | | | | | | | | | | | | | | | | 1-Below is a list of common prefixes used in the SI and metric systems. Included with each is an abbreviation and meaning. Which set contains an error? a) mega-M 106 b) micro- µ 106 c) deci- d 10¹ ५ 2- Which of the following represents 0.000000009853 g in scientific notations? kilo- k 103 9.853 × 10 g (b) 9.853 x 10g c) 9.853 × 10 g d) 9.853 x 10° g 3- The answer for the following calculation, rounded to the proper number of significant digits, is:0.00435 x 4.632010201 3 a) 0.0202 4 60.0201 c) 0.020149 d) 0.02015 35012 Fort 350mm c) 0.014 d)0.254 4-Convert the 350 micrometer to inches a) 0.048 b) 0.326 5-Convert-140 °F to Kelvin a) 213.15 b)-213.15 177.59 d)-177.59 6- An atom of the Co isotope contains a) 27 protons + 27 neutrons + 33 electrons c) 27 protons +27 electrons + 60 neutrons (b) 27 protons +27 electrons + 33 neutrons27 protons +33 electrons + 27 neutrons 7- Which of the following concepts refers to the agreement of a particular value with the true value? a) Accuracy b) Precision c) Random errors d) Systematic errors 8- Which of the following statements iscorrect? a) Covalent bonds result from attraction between oppositely charged ions Mons that possess a negative charge are called cations. c) Ions that possess a positive charge are called anions. d) A molecule of potassium chloride, KCl, consists of one K'ion and one Clion 9- What is the formula for magnesium oxide? cation d) MgO3 (a) MgO Mg20 c) Mg203 10- What is the name of Li3N? a) Lithium nitrate b))Lithium nitride c) Lithium (III) nitrated) Lithium (III) nitride 11- The following formula represents nitric acid: a) H₂NO3 c) HNO2 d) H3NO2 12- What is the percent composition of methane (CH4) (molar mass 16.04 g/mol)? 75 C a) 70% Carbon and 30% Hydrogen b) 75% Carbon and 25% Hydrogen 0 c) 80% Carbon and 20% Hydrogen d) 90% Carbon and 10% Hydrogen 13- The empirical formula fora compound that contains: 85.60g C and 14.40g H is: a)C₂H₂CH₂ c)CH3 d)CH4 14- How many Ti atoms are in 3.5g Ti? a) 3.2 x 1023 b)5.2 x 1023 (c) 4.4 × 1022 d) 6.7 x 1024 15- How many moles of oxygen are produced when 3.0 g of KCIO(Mwt.=122.55 g/mol) decomposes completely? 2KCIO3→ 2KCl+302 3,09 a) 0.056 0.025 0.037 d)0.063 15.09 10109 Zn+2HCl→ZnCl2+H2 16- In the reaction: ?? 15.0 g of Zn are reacted with 10.0 g of HCl. How many grams of H₂ will be produced? a)0.46g b) 0.23g c) 0.54g d)0.15g