The correct answer is (1) B < A < D < E < C.
Let us look at the given options:
A. \(H_2O\) (water) - Melting point: 0°C
Water has a relatively low melting point of 0°C. At this temperature, water transitions from a solid (ice) to a liquid state.
B. \(CCl_4\) (carbon tetrachloride) - Melting point: -23°C
Carbon tetrachloride has a lower melting point than water. It is a molecular compound with relatively weak intermolecular forces, leading to a lower melting point.
C. \(SiO_2\) (silicon dioxide) - Melting point: 1713°C
Silicon dioxide, commonly known as quartz or sand, has a very high melting point. It consists of a network structure where each silicon atom is bonded to four oxygen atoms. The strong covalent bonds in this network structure result in a high melting point.
D. \(Mg\) (magnesium) - Melting point: 650°C
Magnesium is a metal, and metals generally have higher melting points than molecular compounds. The metallic bonding in magnesium involves the delocalization of electrons, leading to a relatively high melting point compared to molecular compounds.
E. \(NaCl\) (sodium chloride) - Melting point: 801°C
Sodium chloride, or table salt, has an ionic bond between sodium and chloride ions. Ionic compounds typically have higher melting points than molecular compounds, but lower than network covalent compounds. The strong electrostatic forces between the ions contribute to the higher melting point.
Now, arranging them in increasing order:
1. \(CCl_4\) (-23°C) - Molecular compound with weak forces.
2. \(H_2O\) (0°C) - Molecular compound with stronger forces than \(CCl_4\).
3. \(Mg\) (650°C) - Metal with metallic bonding, higher melting point than molecular compounds.
4. \(NaCl\) (801°C) - Ionic compound with higher melting point than molecular compounds.
5. \(SiO_2\) (1713°C) - Network covalent compound with the highest melting point.
Therefore, the correct arrangement is \(B < A < D < E < C\). |
