small pieces
Some samples of matter appear to have properties of solids, liquids, and/or gases at the same time. This can occur when the sample is composed of many small pieces. For example, we can pour sand as if it were a liquid because it is composed of many small grains of solid sand. Matter can also have properties of more than one state when it is a mixture, such as with clouds. Clouds appear to behave somewhat like gases, but they are actually mixtures of air gas and tiny particles of water liquid or solid . The mass of an object is a measure of the amount of matter in it. One way to measure an objects mass is to measure the force it takes to accelerate the object. It takes much more force to accelerate a car than a bicycle because the car has much more mass. A more common way to determine the mass of an object is to use a balance to compare its mass with a standard mass. Although weight is related to mass, it is not the same thing. Weight refers to the force that gravity exerts on an object. This force is directly proportional to the mass of the object. The weight of an object changes as the force of gravity changes, but its mass does not. An astronauts mass does not change just because she goes to the moon. But her weight on the moon is only one-sixth her earth-bound weight because the moons gravity is only one-sixth that of the earths. She may feel weightless during her trip when she experiences negligible external forces gravitational or any other , although she is, of course, never massless. The law of conservation of matter summarizes many scientific observations about matter: It states that there is no detectable change in the total quantity of matter present when matter converts from one type to another a chemical change or changes among solid, liquid, or gaseous states a physical change . Brewing beer and the operation of batteries provide examples of the conservation of matter Figure 1.8 . During the brewing of beer, the ingredients water, yeast, grains, malt, hops, and sugar are converted into beer water, alcohol, carbonation, and flavoring substances with no actual loss of substance. This is most clearly seen during the bottling process, when glucose turns.