1. Which particle-level picture shows a mixture containing only molecular elements?
2. What is the sum of 19.32 m and 1.593×10-1 m rounded to the correct number of significant figures?
A. 1.948 ×10-2 m
B. 19.479 m
C. 19.4783 m
D. 19.48 m
E. 1.9 ×10-2 m
3. Which of the following is considered a molecular compound?
A. CaS
B. O2
C. FeO
D. Fe
E. SO2
4. A criminologist measured the melting point of a substance to determine its identity. Her data are listed below. Which statement best describes her data?
Melting Point (oC)
45.60
45.59
45.28
45.62
A. Three melting points are accurate and one is not accurate.
B. Two melting points are precise.
C. The average should have only 2 significant figures.
D. The data are accurate.
E. Three melting points are precise
5. Which of the following best describes the element chlorine?
A. metallic halogen
B. nonmetallic halogen
C. alkali metalloid
D. nonmetallic noble gas
E. alkaline earth metal
6. Calculate the atomic weight of Katium, a fictional element, if it has two isotopes with these abundances and masses:
35Ka 35.02 amu 10.00%
37Ka 37.01 amu 90.00%
A. 36.00 amu
B. 36.02 amu
C. 35.22 amu
D. 35.18 amu
E. 36.81 amu
7. Which of the following most accurately describes a beaker containing table salt, distilled water, and sand?
A. homogeneous mixture of three elements
B. heterogeneous mixture of three compounds
C. homogeneous mixture of three compounds
D. heterogeneous mixture of one compound and two elements
E. heterogeneous mixture of two compounds and one element
8. How many protons, neutrons, and electrons are found in a chloride ion with the symbol 35Cl-9. What is the name of the chemical compound with the formula, CaO?
A. calcium oxalate
B. calcium oxide
C. calcium(II) oxide
D. calcium monoxide
E. calcium(I) monoxide?
9. What is the name of the chemical compound with the formula, CaO?
A. 35 protons, 17 neutrons, and 16 electrons
B. 17 protons, 35 neutrons, and 17 electrons
C. 17 protons, 18 neutrons, and 17 electrons
D. 17 protons, 18 neutrons, and 18 electrons
E. 17 protons, 25 neutrons, and 18 electrons
10. What is the charge on the lead ion in Pb(CO3)2?
A. 1+
B. 2+
C. 3+
D. 4+
E. 0
11. A sample of fructose, a fruit sugar, C6H12O6, that contains 24 g of carbon also contains _____ g of oxygen.
A. 24 g
B. 32 g
C. 48 g
D. 64 g
E. 96 g
12. What is the formula mass of Al2(CO3)3?
A. 210 g/mol
B. 138 g/mol
C. 78 g/mol
D. 114 g/mol
E. 234 g/mol
13. What is the mass percentage of oxygen in Al2(CO3)3?
A. 32.1%
B. 1.26%
C. 68.2%
D. 61.5%
E. 41.0%
14. When sodium chloride decomposes to its elements, the formulas for the products are:
A. Na2(s) and Cl(s).
B. Na2(s) and Cl2(g).
C. Na2(s) and 2Cl(g).
D. Na(s) and 2Cl(g).
E. Na(s) and Cl2(g).
15. When the mixture of molecules shown in the diagram below undergoes complete reaction, all of these molecules are converted to products. Which of the following equations could represent this reaction?
A. N2 + O2 → 2NO
B. 2N2 + O2 → 2N2O
C. 2N2 + 5O2 → 2N2O5
D. N2 + 3O2 → 2NO3
E. none of the above
16. Which acid is named incorrectly?
A. HClO3 (aq), chloric acid
B. HNO3 (aq), hydronitric acid
C. HNO2 (aq), nitrous acid
D. H2CO3 (aq), carbonic acid
E. HBr (aq), hydrobromic acid
17. What is the charge on the tin ion in the compound SnS?
A. 4+
B. 3+
C. 2+
D. 1+
E. 0
18. How many oxygen atoms are found in 0.500 mol of carbon dioxide?
A. 6.02 * 1023
B. 1.51 * 1023
C. 7.55 * 1022
D. 1.20 * 1024
E. 3.01 * 1023
19. Which are empirical formulas?
i. KCl ii. K2 S2O8 iii. K2 SO4 iv. K4 S2 v. KIO3
A. i and v
B. ii and iv
C. i, iii, and v
D. iv and v
E. iii and iv
20. A compound containing only nitrogen and oxygen is 25.92% nitrogen by mass. What is the empirical formula of the compound?
A. NO5
B. N2O5
C. NO2
D. NO4
E. N2O
21. A compound is analyzed and found to have an empirical formula of C3H6O. Its molecular mass is 116 g/mol. What is its molecular formula?
A. C6H12O2
B. C2H3O
C. C3H6O
D. C9H18O3
E. C6H12O6
22. Based on the particulate pictures and the key, which is the correctly balanced equation for this reaction.
A. A2 + 2AB → 2A2B
B. A + AB → A2B
C. 4A + 4AB → 8A + 4B
D. 2A + 2AB → A4B2
E. A2 + AB →A2B