Smoke is what type of mixture

The Tyndall effect is the scattering of visible light by colloidal particles. All three are examples of colloids. Suspensions may scatter light, but if the number of suspended particles is sufficiently large, the suspension may simply be opaque and the light scattering will not occur.

Figure 2. Figure The table below lists examples of colloidal systems, most of which are very familiar. The dispersed phase describes the particles, while the dispersion medium is the material in which the particles are distributed. Dispersion Medium. Another property of a colloidal system is the observed when the colloids are studied under a light microscope. The colloids scintillate, reflecting brief flashes of light because the colloidal particles move in a rapid and random fashion.

This phenomenon, called Brownian motion, is caused by collisions between the small colloidal particles and the molecules of the dispersion medium. Butter and mayonnaise are examples of a class of colloids called emulsions. An emulsion is a colloidal dispersion of a liquid in either a liquid or a solid.

A stable emulsion requires an emulsifying agent to be present. Mayonnaise is made in part of oil and vinegar. Since oil is nonpolar and vinegar is an aqueous solution and polar, the two do not mix and would quickly separate into layers. Mercury 3. Chlorine 4. Bromine Select the correct answer using the code given below : A. Which one among the following colours has the highest wavelength?

Violet B. Green C. Yellow D. Red -- View Answer 4. Which one among the following is not a correct statement? Cathode rays are negatively charged particles B. Cathode rays are produced from all the gases C. Electrons are basic constituents of all the atoms D. Hydrogen ions do not contain any proton -- View Answer 5. The carbon combines with oxygen to produce carbon dioxide until all that is left at the end of the fire is the ash — the minerals.

Smoke inhalation is the primary cause of death in victims of indoor fires. Depending on the house contents, the smoke generated can be extremely toxic or irritating. For example, burning plastics often produce soot and poisonous gases like carbon monoxide and hydrogen chloride. Another danger is that smoke contains flammable compounds.

With increased oxygen, these can ignite either through open flames or by their own temperature. This leads to a backdraught or flashover effect. Smoke also obscures visibility. This makes it difficult to evacuate from a fire. A rock, for example, is a solid.

In contrast, liquids have fixed volumes but flow to assume the shape of their containers, such as a beverage in a can. Gases , such as air in an automobile tire, have neither fixed shapes nor fixed volumes and expand to completely fill their containers. Whereas the volume of gases strongly depends on their temperature and pressure the amount of force exerted on a given area , the volumes of liquids and solids are virtually independent of temperature and pressure.

Matter can often change from one physical state to another in a process called a physical change. For example, liquid water can be heated to form a gas called steam, or steam can be cooled to form liquid water. However, such changes of state do not affect the chemical composition of the substance. A pure chemical substance is any matter that has a fixed chemical composition and characteristic properties. Very few samples of matter consist of pure substances; instead, most are mixtures, which are combinations of two or more pure substances in variable proportions in which the individual substances retain their identity.

Air, tap water, milk, blue cheese, bread, and dirt are all mixtures. If all portions of a material are in the same state, have no visible boundaries, and are uniform throughout, then the material is homogeneous. Examples of homogeneous mixtures are the air we breathe and the tap water we drink. Homogeneous mixtures are also called solutions. Thus air is a solution of nitrogen, oxygen, water vapor, carbon dioxide, and several other gases; tap water is a solution of small amounts of several substances in water.

The specific compositions of both of these solutions are not fixed, however, but depend on both source and location; for example, the composition of tap water in Boise, Idaho, is not the same as the composition of tap water in Buffalo, New York.

Although most solutions we encounter are liquid, solutions can also be solid. Solid solutions of two or more metals are commonly called alloys. If the composition of a material is not completely uniform, then it is heterogeneous e. Mixtures that appear to be homogeneous are often found to be heterogeneous after microscopic examination. Milk, for example, appears to be homogeneous, but when examined under a microscope, it clearly consists of tiny globules of fat and protein dispersed in water.

The components of heterogeneous mixtures can usually be separated by simple means. Solid-liquid mixtures such as sand in water or tea leaves in tea are readily separated by filtration, which consists of passing the mixture through a barrier, such as a strainer, with holes or pores that are smaller than the solid particles. In principle, mixtures of two or more solids, such as sugar and salt, can be separated by microscopic inspection and sorting. More complex operations are usually necessary, though, such as when separating gold nuggets from river gravel by panning.

First solid material is filtered from river water; then the solids are separated by inspection. If gold is embedded in rock, it may have to be isolated using chemical methods.