15. Write the chemical formulas or names of the following ionic compounds. (8pts) \( \begin{array}{ll}\text { a. barium fluoride } & \text { c. } \mathrm{Cu}_{2} \mathrm{O} \\ \text { b. mercury(II) phosphate } & \text { d. } \mathrm{Na}_{2} \mathrm{SO}_{4}\end{array} \) 16. Write the chemical formulas or names of the following molecular compounds. (8pts) \( \begin{array}{ll}\text { a. dichlorine heptoxide } & \text { c. } \mathrm{SF}_{6} \\ \text { b.chlorine dioxide } & \text { d. } \mathrm{N}_{2} \mathrm{O}\end{array} \)

5 What is meant by the term hygroscopic when referring to brake fluid?

The electronic configuration of one element is \(1s^ 2 2s^ 2 2p^ 6 3s^ 2 3p^ 6 3d^ { 10} 4s^ 1\). What is same group which is recently discovered?

What does word root indicate in IUPAC name? b. Write the suffix for doubly bonded \( (\mathrm{C}=\mathrm{C}) \) alcohol. c. Ifsame substituent is repeated thrice, which prefix is added to word root? \& Write IUPAC name of \( \mathrm{CH}_{3}-\mathrm{CH}(\mathrm{CI})-\mathrm{CH}_{2}-\mathrm{COOH} \). e. Which group is selected as suffix if -OH and -CHO both are present in the compound?

At what temperatures is an exothermic reaction spontaneous? A. At higher temperatures when the change in entropy is negative B. At no temperatures C. At all temperatures all the time D. At all temperatures when the change in entropy is positive

57. Rappresenta le equazioni delle seguenti reazioni specificando il nome dei prodotti. \( \begin{array}{ll}\text { a) ossidazione dell'esano } & \text { c) dibromurazione dell'esano } \\ \text { b) monoclorurazione del butano } & \text { d) ossidazione del propano }\end{array} \)