Ch. 3: Properties Of Matter

The correct answer is "anything that takes up space and has mass." This definition accurately describes matter, as it encompasses all physical substances and objects that occupy space and have mass. It includes both tangible materials like solids, liquids, and gases, as well as intangible particles like atoms and molecules. This definition is widely accepted in the scientific community and aligns with the fundamental properties and characteristics of matter.

Chemical properties describe the behavior of matter based on its ability to undergo chemical reactions and change into new substances. This includes characteristics such as reactivity, flammability, and stability. By studying chemical properties, scientists can understand how different substances interact and transform, leading to advancements in various fields such as medicine, materials science, and environmental studies.

Density is defined as the amount of matter or mass contained within a given space or volume. It is a measure of how closely packed the particles or molecules are in a substance. It is not related to the weight or size of the object, but rather to the concentration of mass within a specific area. The higher the density, the more mass is present in a given volume, while a lower density indicates less mass in the same volume.

The correct answer is "Meniscus." The meniscus is the curved surface of a liquid, typically seen in a container, where the liquid is higher at the edges and lower in the center. This curvature is caused by the adhesive forces between the liquid and the container, which pull the liquid up along the sides. The meniscus can be concave or convex, depending on the properties of the liquid and the container.

The given answer is incorrect. Physical changes do change the form of a substance, but they do not change its chemical composition. Examples of physical changes include melting, freezing, boiling, and dissolving. In these changes, the substance may change its state (solid, liquid, or gas) or its physical properties (such as size, shape, or color), but its chemical identity remains the same.

To find the volume of a floating object, it is necessary to use another object to hold it underwater. This is because the volume of an object can be determined by measuring the amount of water it displaces when submerged. By using another object to hold the floating object underwater, the displacement of water can be accurately measured, allowing for the calculation of the object's volume.

The given answer correctly identifies water freezing to become ice cubes and a piece of wood changing shape as examples of physical changes. In both cases, the substances undergo a change in their physical properties without any alteration in their chemical composition. Freezing water causes it to solidify and form ice cubes, while a piece of wood changing shape involves a change in its form or structure without any chemical reactions taking place. These examples demonstrate physical changes where the substances involved undergo transformations in their physical states or appearances.

A physical change refers to a change in a substance that does not alter its chemical composition. It only affects the physical properties of the substance, such as its shape, size, or state of matter (solid, liquid, or gas). Examples of physical changes include melting ice, boiling water, or crushing a can. These changes do not result in the formation of a new substance, but rather alter the appearance or behavior of the existing substance.

Soured milk is an example of a chemical change because the process of souring involves the breakdown of lactose (a sugar in milk) by bacteria, resulting in the production of lactic acid. This change in composition and the formation of a new substance (lactic acid) is characteristic of a chemical change.