Chemistry Test Answer

Exam Name___________________________________ MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) What is the physical state in which matter has no specific shape but does have a specific volume? A) solid B) ice C) gas D) liquid E) salts 1) 2) Which one of the following has the element name and symbol correctly matched? A) Mg, manganese B) Sn, silicon C) P, potassium D) Ag, silver E) C, copper 2) 3) If matter is uniform throughout and cannot be separated into other substances by physical means, it is __________. A) a compound B) an element C) a homogeneous mixture D) either an element or a compound E) a heterogeneous mixture 3) 4) Which of the following is an illustration of the law of constant composition? A) Water is 11% hydrogen and 89% oxygen by mass. B) Water can be separated into other substances by a chemical process. C) Water boils at 100°C at 1 atm pressure. D) Water is a compound. E) Water and salt have different boiling points. 4) 5) In the following list, only __________ is not an example of a chemical reaction. A) the rusting of iron B) the condensation of water vapor C) a burning candle D) dissolution of a penny in nitric acid E) the formation of polyethylene from ethylene 5) 6) Which one of the following is not an intensive property? A) mass B) density C) melting point D) temperature E) boiling point 6) 7) Which calculation clearly shows a conversion between temperatures in degrees Celsius, t(°C), and temperature in Kelvins, T(K)? A) T(K) = t(°C) B) T(K) = t(°C) + 273.15 C) T(K) = [t(°C) - 32] / 1.8 D) T(K) = 273 - t(°C) E) T(K) = [t(°C) + 32] × 1.8 7) 1 8) Precision refers to __________. A) how close a measured number is to other measured numbers B) how close a measured number is to infinity C) how close a measured number is to the true value D) how close a measured number is to zero E) how close a measured number is to the calculated value 8) 9) The number with the most significant zeros is __________. A) 250000001 B) 2.501 × 10-7 C) 2.5100000 D) 0.02500001 E) 0.00002510 9) 10) Consider the following selected postulates of Dalton's atomic theory: (i) Each element is composed of extremely small particles called atoms. (ii) Atoms are indivisible. (iii) Atoms of a given element are identical. (iv) Atoms of different elements are different and have different properties. Which of the postulates is(are) no longer valid? A) (iii) only B) (ii) and (iii) C) (ii) only D) (i) and (ii) E) (iii) and (iv) 10) 11) Which pair of substances could be used to illustrate the law of multiple proportions? A) CH4, C6H12O6 B) SO2, H2SO4 C) CO, CO2 D) H2O, O2 E) NaCl, KCl 11) 12) The gold foil experiment performed in Rutherford's lab __________. A) was the basis for Thompson's model of the atom B) confirmed the plum-pudding model of the atom C) led to the discovery of the atomic nucleus D) proved the law of multiple proportions E) utilized the deflection of beta particles by gold foil 12) 13) All atoms of a given element have the same __________. A) number of protons B) mass C) number of electrons and neutrons D) number of neutrons E) density 13) 2 14) An atom of the most common isotope of gold, 197Au, has __________ protons, __________ neutrons, and __________ electrons. A) 118, 79, 39 B) 79, 118, 118 C) 197, 79, 118 D) 79, 118, 79 E) 79, 197, 197 14) 15) In the periodic table, the elements are arranged in __________. A) order of increasing metallic properties B) order of increasing neutron content C) order of increasing atomic number D) alphabetical order E) reverse alphabetical order 15) 16) Which pair of elements would you expect to exhibit the greatest similarity in their physical and chemical properties? A) H, He B) O, S C) Si, P D) C, N E) K, Ca 16) 17) The elements in groups 1A, 6A, and 7A are called, __________, respectively. A) alkali metals, chalcogens, and halogens B) halogens, transition metals, and alkali metals C) alkaline earth metals, transition metals, and halogens D) alkali metals, halogens, and noble gases E) alkaline earth metals, halogens, and chalcogens 17) 18) Which one of the following molecular formulas is also an empirical formula? A) C2H6SO B) H2O2 C) C6H6O2 D) H2P4O6 E) C6H6 18) 19) Of the choices below, which one is not an ionic compound? A) PbCl2 B) PCl5 C) MoCl6 D) RbCl E) NaCl 20) Which species below is the nitride ion? A) N 3B) NO2- D) NO3- E) Na+ 21) Which one of the following compounds is copper(I) chloride? A) Cu2Cl B) Cu3Cl2 C) CuCl2 D) CuCl E) Cu2Cl3 22) Which metal does not form cations of differing charges? A) Fe B) Sn C) Na D) Cu E) Co 19) 20) C) NH4+ 3 21) 22) ESSAY. Write your answer in the space provided or on a separate sheet of paper. 23) Write the formula of the compound formed between a. NH4+ and SO4 2– __________________________________________ b. Sodium and sulfur _________________________________________________ 24) Write the name/ formula of the following: a.Li3PO4____________________________________________________________________________ b.Fe2(SO4)3_________________________________________________________________________ c. P4O10____________________________________________________________________________ 25) For 79Se2– Write the a. atomic number ___________________ b. Mass number ____________________ c. number of electrons _______________ d. Number of protons _______________ d. Number of neutrons_______________ 4 26) Materials that are less dense than water will float on water. A sample of carbon tetra chloride has a mass of 39.73 g an d a volum e of 25.00 mL. a. What is its density? b. Will carbon tetrachloride float on water? (Density of water is 1 g /mL) 5