Chapter 4 Flashcards
- Explain the scientific process in detail.
It is a way of gaining information (facts) about the world by forming possible solutions to questions, followed by rigorous testing to determine if the proposed solutions are valid. Requires a systematic search for information and continual checking and rechecking to see if previous ideas are still supported by new information. If the new evidence is not supportive, scientists discard or change their original ideas. Scientific ideas undergo constant reevaluation, criticism, and modification. It involves several important identifiable components, including careful observation, asking questions about observed events, the construction and testing hypotheses, an openness to new information and ideas, and a willingness to submit one’s ideas to the scrutiny of others.
- Why is pseudoscience bad?
It’s a deceptive practice that uses the appearance or language of science to convince, confuse, or mislead people into thinking that something has scientific validity when it does not.
- Define matter, the states of, and what it is made of? Can you label the parts of an atom? Isotopes, ions, pH, acid, base, activation energy, catalyst.
Matter is anything that has mass and takes up space. The kinetic molecular theory describes the structure and activity of matter. It states that all matter is made up of one or more kinds of smaller sub-units (atoms) that are in constant motion. The atom is the fundamental unit of matter. There are 92 types of atoms found in nature, with each being composed of Protons (Positively charged), Neutrons (Neutral, is a proton + electron together), and Electrons (Negatively charged). Each kind of atom forms a specific type of matter known as an element. All atoms of the same element have the same number of protons and electrons but may vary in the number of neutrons. Isotopes are atoms of the same element that differ from one each another in the number of neutrons they contain. An acid is any compound that releases H ions in a situation. A base is any compound that accepts H ions in a solution. The concentration of an acid or base solution is given by a number called pH. The pH scale measures H ion concentration. The scale is inverse and logarithmic. 7=neutral, 0-6=acidic(fewer OH- than H+), 8-14=basic(more OH- than H+). Activation energy is the initial input of energy required to start a reaction. A catalyst is a substance that alters the rate of reaction, without being consumed or altered itself in the process. Catalysts can reduce activation energy. A catalytic converter in an automobile brings about more complete burning of fuel resulting in less air pollution.
- Briefly explain the reactions for the photosynthesis and aerobic cellular respiration.
Living organisms contain enzymes that reduce the activation energy needed to start reactions. Photosynthesis is a process used by plants to convert inorganic material into organic material using light. Carbon dioxide + water (in the presence of sunlight) produces glucose + oxygen. Aerobic Cellular Respiration is the process that uses oxygen to break down large, organic molecules into smaller inorganic molecules (releases energy organisms can use). Glucose + oxygen produces carbon dioxide + water + energy.
- What is energy, how is it used?
Energy is the ability to preform work. Work is done when an object is moved over a distance. Kinetic energy is the energy contained by moving objects. Potential energy is energy due to relative position.
- Explain the first and second laws of thermodynamics in detail and be able to use examples to explain each law.
1st Law: Energy cannot be crated or destroyed; it can only be changed from one form to another. When you turn a light bulb, electrical energy is converted into light energy. 2nd Law: When converting energy from one form to another, some of the useful energy is lost. Entropy is the energy that cannot be used to do useful work. When you leave a cup of hot coffee on a table, it eventually cools down because heat energy is transferred t the surrounding air, increasing the overall entropy of the system.
