Chemistry 208 All QUIZ Essay

The Scientific Method tempo 1 Performing Experiments tincture 2 Making Observations Step 3 Proposing a Hypothesis Step 4 Confirming the Hypothesis Step 5 Proposing a Scientific Law Scientific Notation It is a mathematical expression in which a number is expressed as N x 10n where N contains only one nonzero digit to the left of the decimal and n is an integer. Rules for Determining Significant Figures (digits) -All nonzero digits be significant figures -Counting begins from the left with the first nonzero number -Zeros between nonzero digits be counted as sig.Figures -Terminal zeros (zeros to the right of the right of a number) are always significant if the honor contains a decimal point. Ex 2. 3700 g 5 significant figures 17. 50 mL 4 significant figures Rule 1- In calculations involving measured determine (with a certain of sig. figs), the number of sig figs in the closing answer depends on the operation performed. Rule 2- In multiplication and division of measured quantiti es, the final answer contains the same number of sig figs as are in the criterion with the least number of sig figs.Rule 3- In the final answer of a calculation involving exact numbers, unit conversion factors and constants, the number of significant figures is impose by the measured quantity involved. Density = Mass/ Volume return The term matter is used to describe things that occupy space and are perceivable by our senses. It can be classifies in terms of its forcible state or chemical composition. Elements composed of one type of atom. assort as a metal, nonmetal or metalloid.Compound a gang of elements in a definite proportion. Atoms of each individual elements are chemically combined to form the compound. A chemical change can shatter down a compound into its individual elements. Mixture a non-pure effect made of 2 or more elements or compounds that can be separated by physical procedures. Protons have a positive charge, base in the nucleus. Neutrons have no charge, f ound in the nucleus. Electrons have a negative charge.The atomic number of an element is equal to the number of protons in the nucleus of its atoms. The mass number is equal to the number of protons and neutrons in the atom. To take care the number of neutrons, subtract the atomic number from the mass number. Molecules are a combination of atoms in a definite proportion e. g. , molecule of water system Ions are charged species formed by loss or pretend of electron(s) from an atom. Loss of electron cation (positively charged) Gain of electron anion (negatively charged)