A compound containing sulfur and fluorine contains 8.00 g of S and 9.50 g of F. Which combination of S and F masses represents a different compound that obeys the Law of Mul-tiple Proportions? (LO 2.8) (a) 32.0 g of S and 38.0 g of F (b) 4.00 g of S and 4.75 g of F (c) 8.00 g of S and 10.5 g of F (d) 16.0 g of S and 57.0 g of F

Which experiment and subsequent observation led to the discovery that atoms contain negatively charged particles, now known as electrons? (LO 2.10–2.12) (a) Oil is sprayed into a chamber and the speed at which the oil droplets fall is measured with and without an applied voltage. X rays in the chamber knock electrons out of air molecules. The electrons stick to the oil pro-ducing an overall negative charge on the drops. Adjusting the voltage changes the speed at which the negatively charged oil droplets fall. (b) When a high voltage is applied across metal electrodes at opposite ends of a sealed glass tube, a cathode ray is produced. The cathode ray is repelled by a negatively charged plate. (c) A radioactive substance emits alpha particles, which are directed at a thin gold foil. Most of the alpha par-ticles pass through the foil, but a few alpha particles are slightly deflected and some even bounce back toward the radioactive source. (d) The mass of different elements in a pure chemical com-pound are measured. Different samples of the compound always contains the same proportion of elements by mass.

Refer to a periodic table. Which pair of elements do you expect to be most similar in their chemical properties? (LO 2.3) (a) K and Cu (b) O and Se (c) Be and B (d) Rb and Sr

What is the atomic weight of an element that consists of two naturally occurring isotopes? The first isotope has a mass of 84.911 and an abundance of 72.17% and the second isotope has a mass of 86.909 and an abundance of 27.83%. (LO 2.15) (a) 85.47 (b) 86.35 (c) 85.91 (d) 85.17

Identify the location of the element in period 4, group 6A and classify it as a metal, nonmetal, or semimetal. (LO 2.2) (a) Element in position a; nonmetal (b) Element in position b; metal (c) Element in position c; semimetal (d) Element in position d; metal

Which description of an element is incorrectly matched with its location in the periodic table? (LO 2.5–2.6)

(a) Element 3—An element in the transition metal group that is a good conductor of electricity. (b) Element 2—An element that is in the halogen group and does not conduct electricity. (c) Element 4—An element in alkali metal group that is found in its pure form in nature. (d) Element 1—An element that is a solid at room tempera-ture, brittle, and a poor conductor of electricity.

How many protons, neutrons, and electrons are present in an atom of 2 206Pb? (LO 2.14) (a) 82 protons, 206 neutrons, 82 electrons (b) 124 protons, 82 neutrons, 124 electrons (c) 82 protons, 124 neutrons, 82 electrons (d) 82 protons, 82 neutrons, 124 electrons