6. How does the ground state electron configuration of the hydrogen atom differ from that of a ground state helium atom? a. Hydrogen has one electron in a higher energy level. b. Hydrogen has two electrons in a lower energy level. \( \begin{array}{l}\text { c. Hydrogen contains a half-filled orbital. } \\ \text { d. Hydrogen contains a completely filled orbital. }\end{array} \) \( \begin{array}{l}\text { 7. Which electron configuration represents an atom in an excited state? } \\ \begin{array}{ll}\text { a. } 1 s^{2} 2 s^{2} 2 p^{6} & \text { c. } 1 s^{2} 2 s^{2} 2 p^{5} \\ \text { b. } 1 s^{2} 2 s^{2} 2 p^{5} 3 s^{1} & \text { d. } 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{1}\end{array} \\ \begin{array}{ll}\text { 8. Which of the following represents an impossible electron configuration? } \\ \begin{array}{ll}\text { a. } 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{5} & \text { c. } 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{3} 3 p^{6} 4 s^{2} 3 d^{2}\end{array} \\ \text { b. } 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{1} & \text { d. } 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6}\end{array}\end{array} \).

[TRUE or FALSE?] Ionic bonds form between metals and non- metals. \( \begin{array}{r}\text { [FALSE]: Metals form NEGATIVE ions and } \\ \text { non-metals form POSITIVE ions as } \\ \text { electrons are SHARED to form covalent } \\ \text { bonds }\end{array} \) \( \begin{array}{r}\text { [FALSE]: Electrons are SHARED to form } \\ \text { COVALENT bonds between metals and } \\ \text { non-metals }\end{array} \) \( \begin{array}{r}\text { [TRUE]: Metals form POSITIVE ions and } \\ \text { non-metals form NEGATIVE ions as } \\ \text { electrons are TRANSFERRED. }\end{array} \)

b) Write structural formulae for the following compounds (i) \( 2,3,3,4 \) - tetra methyl pent - 1 - ene (ii) Tetralodo methane (iii) 2,5, di methyl hexane (iv) Heptane (v) Pent- 2 - yne

6. How does the ground state electron configuration of the hydrogen atom differ from that of a ground state helium atom? a. Hydrogen has one electron in a higher energy level. b. Hydrogen has two electrons in a lower energy level. \( \begin{array}{l}\text { c. Hydrogen contains a half-filled orbital. } \\ \text { d. Hydrogen contains a completely filled orbital. }\end{array} \) \( \begin{array}{l}\text { 7. Which electron configuration represents an atom in an excited state? } \\ \begin{array}{ll}\text { a. } 1 s^{2} 2 s^{2} 2 p^{6} & \text { c. } 1 s^{2} 2 s^{2} 2 p^{5} \\ \text { b. } 1 s^{2} 2 s^{2} 2 p^{5} 3 s^{1} & \text { d. } 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{1}\end{array} \\ \begin{array}{ll}\text { 8. Which of the following represents an impossible electron configuration? } \\ \begin{array}{ll}\text { a. } 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{2} 3 d^{5} & \text { c. } 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{3} 3 p^{6} 4 s^{2} 3 d^{2}\end{array} \\ \text { b. } 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6} 4 s^{1} & \text { d. } 1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{6}\end{array}\end{array} \).

\( \mathrm{X}_{2}\left(\mathrm{SO}_{4}\right)_{3} \) Weak base 1- Mention two different methods to dissolve the ppt. (A). 2- Find the mass of ppt. (A) + solution (B) which is produced from 26 g of \( \left.\mathrm{X}_{2}\left(\mathrm{NO}_{3}\right)_{2}\right)_{2} \).

\( \mathrm{X}_{2}\left(\mathrm{SO}_{4}\right)_{3} \) Weak base 1- Mention two different methods to dissolve the ppt. (A). 2- Find the mass of ppt. (A) + solution (B) which is produced from 26 g of \( \left.\mathrm{X}_{2}\left(\mathrm{NO}_{3}\right)_{2}\right)_{2} \).