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Solid
1. Solid is one of the major states of matter. It is characterized by structural rigidity and resistance to changes of shape or volume. Unlike a liquid, a solid object does not flow to take on the shape of its container, nor does it expand to fill the entire volume available to it like a gas does. The atoms in a solid are tightly bound to each other, either in a regular geometric lattice or irregularly one.
2. The branch of physics that deals with solids is called solid-state physics, and is the main branch of condensed matter physics (which also includes liquids). Materials science is primarily concerned with the physical and chemical properties of solids. Solid-state chemistry is especially concerned with the synthesis of novel materials, as well as the science of identification and chemical composition.
3. The forces between the atoms in a solid can take a variety of forms. For example, a crystal of sodium chloride (common salt) is made up of ionic sodium and chlorine, which are held together by ionic bonds. In diamond or silicon, the atoms share electrons and form covalent bonds. In metals, electrons are shared in metallic bonding. Some solids, particularly most organic compounds, are held together with van der Waals forces resulting from the polarization of the electronic charge cloud on each molecule. The dissimilarities between the types of a solid result from the differences between their bonding.

Ответы:

+ A solid’s properties are quite different from those of a gas or a liquid due to its structure and the ability to resist.

− It has been an accepted fact that the quantity of atoms in a solid’s lattice is permanent.

− The existence of various solids can be explained by different types of their lattices.

− It is possible to change a solid’s state modifying its chemical bonds.

Решение:

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Утверждение «A solid’s properties are quite different from those of a gas or a liquid due to its structure and the ability to resist» («Свойства твердого тела совершенно отличны от свойств газа или жидкости») соответствует содержанию текста: «It is characterized by structural rigidity and resistance to changes of shape or volume. Unlike a liquid, a solid object does not flow to take on the shape of its container, nor does it expand to fill the entire volume available to it like a gas does» («Оно характеризуется жесткой структурой и сопротивлением на изменения формы или объема. В отличие от жидкости, твердое тело не течет и не принимает форму своего контейнера, не расширяется, чтобы заполнить объем целиком, как при этом ведет себя газ») (фрагмент 1).
ответ тест i-exam

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Iodine, a steel-gray solid, readily vaporizes when heated. The vapor is violet in colour. If the vapor is allowed to cool, it passes directly back into the solid state. This process of passing from the solid state to the vapor state and then back to the solid state without the formation of a liquid is called sublimation. If a saturated solution of potassium nitrate is heated and then allowed to cool, crystals of the substance form on the bottom of the vessel. These are formed by precipitation, which takes place during the cooling process.
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Iodine readily vaporizes …

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We use metals for a variety of engineering purposes. Some metals have ductile properties. If a metal is ductile, it can be pressed into a new shape. Copper is an example of this. It is a ductile metal because it can be stretched into another shape. Lead can be also pressed into a new shape.
Copper is a good conductor of electricity. We often use it for electrical conductors. And lead can be used for electrical cables because it resists corrosion.
Cast iron is unlike copper and lead. Its shape cannot be altered and it is not able to resist corrosion.
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What kind of conductor is copper?

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Plastic Materials
1. Plastic materials are not found in nature. Plastic is formed by extrusion or injection molding under very high pressure. It can be molded into any desired shape. Organic plastics are divided into two general groups: thermosetting and thermoplastic. The thermosetting group becomes rigid through a chemical change that occurs when heat is applied. These plastics cannot be remolded. The thermoplastic group remains soft at high temperatures and must be cooled before becoming rigid. This group is not used generally as a structural material.
2. Plastics are rapidly becoming important construction materials because of their great variety, strength, durability and lightness. Plastics are light. The benefits of light weight coupled with good strength and absence of corrosion offer tremendous potential as alternatives to traditional building materials. A given volume of polythene weights less than one-eighth of an equal volume of iron and less than half of the same volume of aluminum.
3. Plastics are used in the industry and in the household: from rockets and electronics to toys and house ware. Plastic products offer many advantages over the materials they replace, such as ease of handling, lower maintenance costs and rapidity of assembly. The insulation and dielectric properties of plastics led to their early use in the electrical engineering industry, which was followed by special application in mechanical engineering.
4. Using of plastics as materials for a construction in the form of sheets, rods or tubes is substituting the conventional metals. Plastics offer a lot of properties for the designs. Plastics have now been developed to such an extent that they can be applied to almost every branch of building, from the laying of foundations to the final coat of paint.
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Plastic Materials
1. Plastic materials are not found in nature. Plastic is formed by extrusion or injection molding under very high pressure. It can be molded into any desired shape. Organic plastics are divided into two general groups: thermosetting and thermoplastic. The thermosetting group becomes rigid through a chemical change that occurs when heat is applied. These plastics cannot be remolded. The thermoplastic group remains soft at high temperatures and must be cooled before becoming rigid. This group is not used generally as a structural material.
2. Plastics are rapidly becoming important construction materials because of their great variety, strength, durability and lightness. Plastics are light. The benefits of light weight coupled with good strength and absence of corrosion offer tremendous potential as alternatives to traditional building materials. A given volume of polythene weights less than one-eighth of an equal volume of iron and less than half of the same volume of aluminum.
3. Plastics are used in the industry and in the household: from rockets and electronics to toys and house ware. Plastic products offer many advantages over the materials they replace, such as ease of handling, lower maintenance costs and rapidity of assembly. The insulation and dielectric properties of plastics led to their early use in the electrical engineering industry, which was followed by special application in mechanical engineering.
4. Using of plastics as materials for a construction in the form of sheets, rods or tubes is substituting the conventional metals. Plastics offer a lot of properties for the designs. Plastics have now been developed to such an extent that they can be applied to almost every branch of building, from the laying of foundations to the final coat of paint.
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Why do plastics replace traditional building materials?