3 Part One. The Predicate

Molecules in Solids
Having their own shape is a characteristic feature of solids since they have their own shape rather than that of the container (as for liquids and gases) and generally do not flow, the extent o f molecular motion in a solid is even more limited than that in a liquid. True solids are crystalline, bounded by plane surfaces that meet in a definite dihedral angle, and have a characteristic melting point. The molecules in a solid have the same temperature, and if they are molecules of the same substance, they are moving at the same average velocity, the motion of molecules in a solid must be confined, and, probably, it is a vibration or oscillation about a fixed point.

Crystals composed of molecules may evaporate in a manner similar to that of liquids. This phenomenon is called sublimation, and it may.be noticed in solid carbon dioxide (dry icc), paradichlorobcnzcnc, camphor, and many odorous solids. Non-molecular solids show little tendency to sublime. The Van dcr Waals force between the particles in molecular solids is, apparently, less in general than the coulomb forces between ions in non-molecular solids. As with liquids, solids vary greatly in their tendency to sublime, and the rate of sublimation varies with the temperature and inversely with the pressure. In some solids the ciystal is composed of molecules in a pattern that repeats.

Mashq 3. Matnning asosiy tarkibini bir nechta jumlalarda ko’rsating.

Mashq 4. Matnning rejasini tuzing.

Mashq5. Jumlalarni o'qing va agar ular matn mazmuniga mos kelsa, ayting. Agar yo'q bo'lsa, ularni tuzating.
1. Liquids and gases usually have the form of their container.2. Characteristic feature o f solids is that they have their own form.3. Crystalline solids cannot evaporate like liquids. 4. Sublimation is the evaporation of solids. 5. The rate of sublimation increases with the rise of the temperature and the pressure. 6. Planar structure of the carbon atoms in graphite makes its properties different from those of a diamond.

Mashq 6. Bir modda ichidagi molekulalarning harakati haqida so'zlovchi matnni toping va rus tiliga tarjima qiling.