Question

0 0 6. The melting point of NH3 is 195 K. The boiling point of NH3 is 240 K. In order to determine the amount of energy required to raise a certain quantity of NH3 from 200 K to 230 K, we need to use values of which thermal properties of NH3? a) heat of vaporization b) heat of fusion c) heat capacity of liquid ammonia d) heat capacity of ammonia vapor e) some two of the above types 7. Calculate the amount of heat lost by the conversion of 8.17 g of Al (s) to A1203 (5) using the following information: 4 Al(s) + 3028 --> 2 A1203(s) H®(kJ/mol) -1676 a) 101 kJ b) 127 kJ c) 203 kJ d) 237 kJ e) 254 kJ 8. Which one of the following statements is TRUE? a) A molecule having all polar bonds always has a dipole moment. b) Among the elements, P, As, and Sb, the most metallic is phosphorus. c) The F-F single bond in fluorine molecules is due to p orbital overlap, therefore it is a # bond. d) A magnesium ion has a smaller radius than an oxide ion. e) Radio waves have a greater frequency than X-rays. 9. For the reaction: H:SeO; + 6 + 4H* Se + 213* + 3 H20 it is observed that the rate of iodide disappearance, -A[1]/At - 3.6 Ms. What is the rate of disappearance of hydrogen ion, -A[H]/At? a) 2.4 M/S b) 0.6 m/s c) 5.4 M's d) 3.6 M's e) 0.9 M/s 10. In which one of the following pairs is the first molecule polar and the second molecule nonpolar? a) H20 and SO2 b) Fz and coc) HF and NaCl d) NHz and BF, e) 02 and H2

Answer 1

we alt= ? 6. AH=PAT need the value of (CP.) Heat Capacity of NH3 liquid 7. 2418) + 302 (9) 2 A2203 alt= [-1616) 2- 48)+36)] 3352 KJ For 4x27g -3352kJ (I for Imole 4616) 8.17 9 8.17 X 3352² 254 kJ 4x2) 8. d) Mg +2 has small radicy than 62 ion iso electioning (Mgt2_ 12-2=10€ o2 = 8+2=10€) 8 +2=10€) ion with higher unclear charge has smaller radics from the egg. ada dl - 2x 3.6 = 1 I d[H+ d[lt+] 4 2.yals dr at 10: a) H2o - Polar b) F₂ non polar c) HE polar soz polar Macht ionic (Polar) (d) NH3 polar e) O2 pron polar BF3 j non polar 42 - noupolar because among ch d[ht] 6 at co polar The correct answer optiould