Earth Science 1 Prologue

1 PROLOGUE Graphical Relationships Graph relationships - states the relationship between the X (independent) and Y (dependent) variables. When stating the relationship, sentences begin with ‘as’. Variable - factors that can possibly change the outcome of an experiment. Controlled Variable - a factor that is kept constant throughout an experiment. Independent Variable - a factor that is purposely changed in an experiment to alter the outcomes. Types of graphs - the four commonly used graphs in Earth Science are direct relationship graphs, indirect relationship graphs, cyclic relationship graphs, and static relationship graphs. Direct Relationship - a positive correlation between variables; as the independent variable increases, the dependent variable increases as well. Indirect Relationship - a negative correlation between variables; as the independent variable increases, the dependent variable decreases. Cyclic Relationship - a repetitive pattern between variables; as the independent variable increases, the dependent variable increases and then decreases forming a continuous repetition. Static Relationship - as one variable is changing, the other remains constant. These graphs are usually represented with vertical or horizontal lines (common with density). Percentage Error - the difference between the measured value and accepted/known value, divided by the accepted/known value and multiplied by 100%. Measured Value - Accepted Value X 100% Accepted Value Rate of Change - the rate in which one quantity changes in response to another quantity. Change in value Time Observation, Inference & Prediction Observation - information collected using the five senses of sight, hearing, touch, taste, or smell. Quantitative Observation - information that is measurable or countable. Qualitative Observation - information that is describable and not measurable. Inference - an interpretation made on observations to give it full meaning. Prediction - an inference based on observations that indicate what will happen in the future. Hypothesis - a prediction made with limited evidence that is tested with an experiment. Experiment - a scientific procedure held to test or prove a given hypothesis. Analysis - an explanation made after evaluating and comparing observations. Conclusion - the summary of an experiment after testing the hypothesis. Density, Mass & Volume Density - the measure of mass per unit of volume. Mass Volume Density of Water - 1g/ml Objects that float on water - less that 1g/ml Objects that sink in water - more than 1g/ml Matter - objects that have a mass and volume. ☆ Solid, Liquid, and Gas are the three states of matter which are differentiated with speed of molecular motion and distance between molecules. ☆ Solids have the least molecular speed and distance between each other, whereas gas has the highest molecular speed and the molecules are spread wide. ☆ When a substance is heated, the molecular motion and distance increases; when it is cooled, the molecular motion decreases and distance decreases as well. ☆ Solid matter is the densest while gases are least dense. Kinetic Energy - measure of the vibration and motion of molecules. Temperature - measure of average kinetic energy of particles in a substance. ☆ Increase in temperature is an increase in volume, which decreases Density. ☆ Decrease in temperature is a decrease in volume, which increases Density. Heat - the transfer of energy from a higher temperature to a lower object. Contraction - the decrease in volume of a matter which can be effects of temperature or pressure. Expansion - the increase in volume of a matter which can be effects of temperature or pressure. Mass - the amount of matter possessed by an object; usually measured in grams. ☆ Mass DOES NOT change whether the substance is heated or cooled. Volume - the amount of space an object takes up; usually measured in cubic centimeters or millimeters. ☆ When a substance is heated, the volume increases due to the increase in molecular motion which ultimately increases the space between molecules. ☆ When a substance is cooled, the volume decreases due to the decrease in molecular motion which ultimately decreases the space between molecules. Atom - The smallest unit of matter that contains the same properties as a larger fraction of that matter. Element - Matter that is made up of solely one kind of atom. Molecule - Atoms that are chemically bound together and have all the chemical properties of the compound molecule.