General Chemistry Study Guide
Chemistry Final Study Guide
Matter as anything that has mass and takes up space.
Significant figures refers to digits that were measured.
When rounding calculated numbers, we pay attention to significant figures so we do not overstate the accuracy of our answers.
Rules:
-All nonzero digits are significant.
-Zeroes between two significant figures are themselves significant.
-Zeroes at the beginning of a number are never significant.
-Zeroes at the end of a number are significant if a decimal point is written in the number.
-When addition or subtraction is performed, answers are rounded to the least significant decimal place.
-When multiplication or division is performed, answers are rounded to the number of digits that corresponds to the least number of significant figures in any of the numbers used in the calculation.
Periodic Table
Isotopes are atoms of the same element with different masses.
Isotopes have different numbers of neutrons.
The periodic table is a systematic catalog of the elements.
Elements are arranged in order of atomic number.
Elements in the same group have similar chemical properties
Nonmetals are on the right side of the periodic table (with the exception of H).
Metalloids border the stair-step line (with the exception of Al, Po, and At).
Metals are on the left side of the chart.
When atoms lose or gain electrons, they become ions.
Cations are positive and are formed by elements on the left side of the periodic chart.
Anions are negative and are formed by elements on the right side of the periodic chart.
Ionic compounds (such as NaCl) are generally formed between metals and nonmetals
Formula weight is the sum of the atomic weights for the atoms in a chemical formula. -Formula weights are generally reported for ionic compounds.
Molecular weight is the sum of the atomic weights of the atoms in a molecule.
Percent Composition (# of atoms)(atomic weight) x 100 (Formula Weight
Matter as anything that has mass and takes up space.
Significant figures refers to digits that were measured.
When rounding calculated numbers, we pay attention to significant figures so we do not overstate the accuracy of our answers.
Rules:
-All nonzero digits are significant.
-Zeroes between two significant figures are themselves significant.
-Zeroes at the beginning of a number are never significant.
-Zeroes at the end of a number are significant if a decimal point is written in the number.
-When addition or subtraction is performed, answers are rounded to the least significant decimal place.
-When multiplication or division is performed, answers are rounded to the number of digits that corresponds to the least number of significant figures in any of the numbers used in the calculation.
Periodic Table
Isotopes are atoms of the same element with different masses.
Isotopes have different numbers of neutrons.
The periodic table is a systematic catalog of the elements.
Elements are arranged in order of atomic number.
Elements in the same group have similar chemical properties
Nonmetals are on the right side of the periodic table (with the exception of H).
Metalloids border the stair-step line (with the exception of Al, Po, and At).
Metals are on the left side of the chart.
When atoms lose or gain electrons, they become ions.
Cations are positive and are formed by elements on the left side of the periodic chart.
Anions are negative and are formed by elements on the right side of the periodic chart.
Ionic compounds (such as NaCl) are generally formed between metals and nonmetals
Formula weight is the sum of the atomic weights for the atoms in a chemical formula. -Formula weights are generally reported for ionic compounds.
Molecular weight is the sum of the atomic weights of the atoms in a molecule.
Percent Composition (# of atoms)(atomic weight) x 100 (Formula Weight