Science Cheat Sheet 2 - Lecture notes 4 PDF

Preview

Summary

science lecture notes...

Description

- A polyatomic ion that appears unchanged on both sides of the equation can be Law of Conservation of Mass: counted as a single unit. - Antoine Lavoisier's 1789 discovery Three common compounds containing - Atoms are neither destroyed nor produced hydrogen are methane CH4, ammonia in a chemical reaction. NH3, and water H2O - The total mass of the products is always - Balance compounds first and single equal to the total mass of the reactants. elements last Balancing Equations: Subscripts/Coefficients Skeleton Equation - If you place a coefficient in front of a - Shows only the formulas of the reactants formula, be sure to balance all the atoms of and the products that formula before moving on. - Determine the reactants for the equation - Add coefficients only in front of formulas. and write them on the left-hand side, Do not change subscripts. separated by a plus sign. - When there is no subscript, it means there - Write the appropriate products on the is 1 atom. right-hand side of the arrow, separated by If element occurs alone and is not a plus sign. diatomic, no subscript is used - Add the notation to indicate the state of the chemicals. They will typically be solid Types of Chemical Reactions - A synthesis reaction involves the (s), liquid (l), gas (g) or aqueous solution combining of two elements into a (aq). compound Formula Equation The reverse of the synthesis reaction is a - A chemical equation representing a decomposition reaction. This reaction chemical reaction in chemical symbols involves the breaking apart of a - Shows chemical formulas, balancing compound intro two separate elements ( coefficients, states, energy. or sometimes compounds) - occurs when the number of the different A single replacement reaction is the atoms of elements in the reactants side is reaction between an element and a equal to that of the products side. compound to produce an element and Coefficients another compound. - Integers placed in front of the formulas. - In a double replacement reaction, two - Show the ratios in which the chemicals are ionic solutions react to produce two new consumed and produced. ionic compounds. One of the compounds - Add balancing coefficients to write a remains in solution while the other one balanced equation forms a precipitate. Rules+ Tips of Balancing - In an acid- base neutralization reaction, an HOFBrINClAt acid and a base react to form a salt and - Eight common non-metal elements which water. are diatomic Combustion: exothermic=produces heat, - Hydrogen, nitrogen, oxygen, fluorine, involves oxygen as an reactant, and chlorine, bromine, iodine, astatine produces water and carbon dioxide - When occured alone ( not in compound) they are written as H2, O2, F2, B2, N2, I2, Cl2, Al2 Polyatomic Groups

Chemistry- Chemical Equations

Predicting Products - Identify the type of reaction involved - Identify the cation and anion of the compounds involved in the reaction, as well as their charges. - Determine whether the products are soluble. - Verify that the reaction is balanced by adding coefficients in front of the reactants and products as necessary to ensure that each type of atom is present on each side of the reaction arrow in equal numbers....