化学：中心科学 英文版 原书第10版 教学课件 作者 美 厄巴那 BROWMN01_001 034PR.pdfVIP

BROWMN01_001-034PR 1/18/05 13:16 Page A-1 Answers to Selected Exercises 6 Chapter 1 (c) 1.95 * 10 g. The sphere weighs 1950 kg, or 4300 lb; the 1.1 (a) Pure element: i, v (b) mixture of elements: vi (c) pure thief is unlikely to be able to carry it. 1.73 (a) Average speed compound: iv (d) mixture of an element and a compound: ii, iii = 7.0393 mihr (b) pace = 8.5236 minmi or 511.42 smi 1.5 (a) 7.5 cm, 2 significant figures (sig figs) (b) 140°C, 2 sig figs 1.76 (a) $2.013 * 10-3L or 0.2013 ¢L (b) $3.397 day 1.8 1.79 (a) 61.5% Au by mass (b) 15 carat gold 1.81 The separa- tion is successful if two distinct spots are seen on the paper. To Given 1 km 1 hr 1 hr Find quantify the characteristics of the separation, calculate a refer- 0.62 min 60 min 60 min mi/hr km/hr km/min km/s ence value for each spot: distance travelled by spot distance travelled by solvent. If the values for the two spots are fairly 1.9 (a) Heterogeneous mixture (b) homogeneous mixture different, the separation is successful. (heterogeneous if there are undissolved