Composition of Matter I. Pure Substances i. A pure substance is either an element or a compound ii. Substances cannot be broken down into simpler components and still maintain the properties of the original substance a. Elements i. If all atoms in a substance are alike, that substance is an element. ii. There are 90 elements found in nature b. Compounds iii. A compound is a substance in which atoms of two or more elements are combined in a fixed proportion I. Mixtures II. A mixture is a material made up of two or more substances that can be easily separated by physical means a. Heterogeneous Mixtures i. A mixture in which different materials can be distinguished easily is called a heterogeneous mixture. ii. You might not be able to spot these mixtures with the naked eye. iii. Some components are easy to see, but others are not iv. The component you might see can be a mixture itself b. Homogeneous Mixtures v. A homogeneous mixture contains two or more gaseous, liquid, or solid substances blended evenly throughout. vi. Vinegar is a homogeneous mixture. It appears clear even though it is made up of particles of acetic acid mixed with water. vii. A solution is a homogeneous mixture of particles so small that they cannot be seen with a microscope and will never settle to the bottom of their container.
1. Chemistry - study of composition, structure, + prop. of matter, processes that matter undergoes, + E in processes
2. Chemical - any subs. with a def. composition; matter is composed of dif. types of atoms; 1 subs. changes to another by reorganizing the way atoms are bonded
Chem. reaction - one or more subs. are converted into different subs.; atoms are re-organized
3. Law of Conservation of matter/mass/energy – matter/mass is neither created nor destroyed in chem. rxn…
Chemistry Chapter 1 Questions:
Atoms: submicroscopic particles that constitute the fundamental building blocks of matter
Molecules: when two or more atoms combined together
-molecules are common in nature
Chemistry: science that tries to understand the behavior of matter by studying atoms and molecules
Scientific knowledge is based on observations and experiments. Plato believed that knowledge came from reasoning and thinking about the ideal world
The scientific method is scientific…
Experiments scientific law
Depends on the amount of matter in a sample
Depends on the type of matter
Quality or condition of a substance that can be observed or measured without changing the substances composition.
States of matter
Def shape, def volume, not compressible
change in composition
Chemical Property: Any characteristic that gives a sample of matter the ability/inability to undergo a change that alters its composition. Examples: Alkali metals react with water; Paper's ability to burn.
Physical Change: Change in which the matter's physical appearance is altered, but composition remains unchanged. (Change in state of matter)
Chemical Change: Change in which one or more kinds of matter are transformed to new kinds of matter with altered compositions (or Chemical…
• Nature science divides into two
– biological science: living things
– physical science: nonliving
Definition of Chemistry:
• Chemistry is the study of the
composition, structure, and properties
of matter, the processes that matter
undergoes, and energy changes that
accompany these processes.
Branches of Chemistry
Is associated with the motion of particles.
Matter – anything that has mass and takes up space or occupied space (EVERYTHING!!!!!)
Classified by their composition.
Called homogeneous when they are uniform (Solution)
Called heterogeneous when they are not uniform.
In a homogeneous mixture, the composition is uniform throughout, and different parts of the mixture are not visible.
In a heterogeneous mixture, the composition is not uniform; it varies from one part of the mixture…
distracted by the other students. All she wanted to do was learn and pass the class with flying colors. It was her second time in the same class and emotions were running high.
She was anxious, nervous and determined to move forward to English Composition two by all means necessary. Mrs. Jones begin to explain to the classroom what…
1. Chemical changes
The changes that occurs in the structure and composition of the matter is known as the chemical change. It is irresible and one directional.
The chemical substance that is formed by the composition of two or more than two elements combined in fixed proportion. It is result of the chemical change between the elements.
Element is the purest form of matter that can neither be created nor can be destroyed.
4. Atomic Number
The number of electron…
Chemistry: the science that seeks to understand the behavior of matter by stuffing what atoms and molecules do.
Observation: Often the first step in the scientific method. An observation must measure or describe something about the physical world.
Theory: A proposed explanation for observations and laws. A theory presents a model of the way nature works and predicts behavior that extends well beyond the observations and laws from which it was formed.
Matter anything that occupies space and has mass; made up of particles
Solid v- definite; s-definite; a- close together; vibrating in place
Liquid v-definite; s-indefinite; a- close together; moving freely
Gas v- indefinite; s- indefinite; a- far apart; motion is random (chaos)
Condensation cool or compress (gas to liquid)
Freezing cool (liquid to solid)
Melting heat (solid to liquid)
Vaporization heat or reduce pressure (liquid to gas)
Sublimation (solid to gas) dry ice