Physical and Chemical Changes Essay

2. a) Liquid nitrogen boiling at -196°C is a physical property because it describes the boiling point of a substance, which is also when it changes state. A change of state, from a liquid to a gas, is a physical property because there is no new substance being created.

Every individual is different in a specific way. Like people, substances have unique qualities, such as properties, which aid chemists to differentiate and identify the particular components the substances consists of. These particular qualities are identified as either physical or chemical properties. Physical properties are properties which do not require a chemical change of its composition in order for the substance to be classified. A few examples of physical properties include color, density, odor, boiling point, melting

The experiment is to observe a variety of chemical reactions and to identify patterns in

A physical change includes a change in the material without affecting its composition, such as the physical state change. However, a chemical change includes the change in the composition of the substance. The change in color, formation of a gas or a solid product, and the production of energy are the evidences of a chemical reaction, thus, of a chemical change.

The composition of a pure substance is constant, and thus pure substances have characteristic physical properties that do not change and this is why we are able to separate each element in this lab experiment. Examples of physical properties that can be used to describe pure substances include solubility, conductivity, magnetism, density, boiling point, and melting point.

Physical Properties: A property that can be observed or measured without changing the chemical identity of the substance.

Objective : To demonstrate the differences between physical and chemical changes while observing the laws of conservation of matter and energy.

4. The following examples do not always indicate chemical change. For example, change in color will always indicate chemical change because the color changes but it does not change the substance’s physical properties. The apparent loss in mass is a phase change; therefore the entire substance goes through a physical change. The apparent disappearance of a substance is a chemical change and will always be a chemical change because it might result of a soluble substance dissolving in a liquid and changes the entire substance in a chemical phase.

Purpose: The purpose of this experiment is to investigate the physical and chemical properties of pure chemical substances by subjecting them to various environmental extremes.

Chemical reactions make new things by rearranging other things. In a chemical reaction, the main change that occurs relates to the way atoms are bonded to each other, in order to change those connections, bonds must be broken and new bonds be formed.

A chemical reaction is a process in which elements or compounds react with one another to create new or different substances. There are two parts to a reaction. Those two parts are the products and the reactants. The reactants are the chemicals or chemical compounds that are going through the reaction itself. The products are chemical elements or chemical compounds that are produced as a result of the reactant or reactants reacting. There are four key indications that there’s a chemical reaction is taking place. Those four signs include a change in color and/or odor, formation of a precipitate or a gas, the release or absorption of energy (light, heat, electricity), and if the reaction is irreversible. Along with this information, there are ways to predict the products of a reaction.

Many outside forces may bend a solid out of its original shape. The ability of a solid to return to its original form after

In The Physics Aristotle deduces that there must be two main principles of change. These principles are 1) matter and 2) form. Matter stays the same in general composition throughout change much as a rock would stay the same even after being broken into several small pieces. Form, however, is what changes through various processes.

When in the process of making an object, properties must, also, be remembered. An archery bow, for example, would not work correctly if it were pre-bent. A bow starts out straight and is bent. This is done to create strain energy and this is what throws the arrow. Most properties stem from engineering stress and engineering strain. These are important when describing materials.

In a process, 701J heat is absorbed and 394J work is done by system. What is