Explain the following statements:



Explain the following statements:
(i) Latent heat of fusion of solid carbon dioxide is much less than that of silicon dioxide.
(ii) Water has its maximum density near 277 K
(iii) Ice floats on surface of water near the melting point


(i) Si${{O}{2}}$ has covalent bonds while C${{O}{2}}$ has Vander Waal’s forces. Hence Si${{O}_{2}}$ has higher heat of fusion.
(ii) Below 277 K and above 277 K, water expands hence its volume increases, density decreases and is maximum at 277 K.
(iii) At 0°C or 273 K, its density is less than that of water hence floats.