HESI A2 Chemistry Updated for 2024-Graded A+

HESI A2 Chemistry Updated for 2024-Graded A+ scientific notation the scientific system of writing numbers -composted of 3 parts: mathematical sign, the significand, and the exponential/logarithm mathematical sign designates whether the number is positive or negative (+/-) significand the base value of the number or the value of the number when all the values of ten are removed exponential/logarithm a multiplier of the significand in powers of 10. a positive exponential multiplies the significand by factors of 10. a negative exponential multiplies the significand my factors of 1/10 tera T-, 10^12, 1 trillion times giga G-, 10^9, 1 billion times mega M-, 10^6, 1 million times kilo k-, 10^3, 1 thousand times hecto h-, 10^2, 1 hundred times deka D-, 10^1, 10 times deci d-, 10^-1, 1 tenth of centi c-, 10^-2, 1 hundredth of milli m-, 10^-3, 1 thousandth of micro µ-, 10^-6, 1 millionth of nano n-, 10^-9, 1 billionth of pico p-, 10^-12, 1 trillionth of femto f-, 10^-15, 1 quadrillionth of metric system a method to measure weight, length, and volume basic units of measurements of the metric system kilo"gram" -grams (weight), liter (volume), meters (length/distance) prefix "kilo"gram -have the same meaning/value regardless of which basic unit of measurement is used -the quantifiers of the measurements used 3 most common temperature systems fahrenheit, celsius, and kelvin fahrenheit (F) the temperature measuring system used only in the U.S., its territories, Belize, and Jamaica -0 degrees F: freezing point of sea water or heavy brine at sea level -32 degrees F: freezing point of pure water at sea level -212 degrees F: the boiling point of pure water at sea level -98.6 degrees F: normal body temp for a person celsius (C) (sometimes called centigrade) a temperature system used in the rest of the world and by the scientific community -0 degrees celsius: freezing point of pure water at sea level -100 degrees celsius: boiling point of pure water at sea level -37 degrees celsius: normal body temp for a person kelvin (K) used only in the scientific community -zero degrees (0K): equals -273.15 degrees celsius and is thought to be the lowest temperature achievable or absolute zero (0) -273K: freezing point of water -373K: boiling point of water -310K: normal body temp of temp for a person, but this is never used atom the basic building block of all molecules nucleus the center of an atom and is composed of protons and neutrons electrons negatively charged spin around the nucleus at various energy levels at fantastic speeds, forming electron clouds protons positively charged neutron no charge at all ground state atoms equal numbers of protons and electrons, making them electrically neutral ion -when an atom is electrically charged; in an ionic state -occurs when it is in a solution or in the form of a chemical compound cation -positive charge an atom in an ionic state will have lost in electrons, resulting in a net positive charge anion -negative charge an atom in an ionic state that will have gained electrons, resulting in a net negative charge periodic table a table of the known elements arranged according to their properties; makes it possible to predict the properties of each element based on its location on the table -made up of a series of rows called periods and columns called groups atomic number the number of protons in the nucleus, and it defines an atom as a particular element (atomic number = number of protons) atomic mass the average mass of each of that elements isotopes (protons+neutrons)