chem ch 4

imported from tyra's quizlets tysm

Reactant

a substance that takes part in and undergoes change during a reaction.

product

A substance produced in a chemical reaction

Law of Conservation of Mass

Matter is not created nor destroyed in any chemical or physical change. Mass before and after a chemical reaction occurs remains constant.

synthesis reaction

Involves two or more simple substances (elements or compounds) combine to form one more complex substance). Usually exothermic

Exothermic

Chemical release more energy than absorbing energy. Get more than you spend

Decomposition

involves a complex compound being broken down or decomposed into two or simpler substances. Usually endothermic because energy required for breaking bonds

Endothermic

Reactions that absorb more energy to break bonds than they release during bond formation. Spend more than you get

non-metal oxide + water

acid

metal oxide + water

base (metal hydroxide)

Metal + non-metal

Simple (binary) salt

Acids decomposes

non-metal oxide and water

Base decomposes

metal oxide and water

Simple (Binary) Salt decomposes

Metal and Non-metal

Combustion

involves the reaction of a hydrocarbon or a carbohydrate with oxygen gas to produce carbon dioxide gas and water

Single Replacement

a reaction between a compound and an element so that the element replaces an element of the same type in the compound. results in a new compound and new element

chemical reactivity

the ability to combine and to chemically bond with each other

what replaces Hydrogen(+) in replacement reactions

Elements above Magnesium

Precipitation

Two soluble salts are combined in a solution, two new salts are formed with one which is not very soluble.

neturalization

reactions occurs between an acid and a base. Products are always water and a salt. generally exothermic

gas formation

A few products of double replacement reactions aren't stabe and spontaneously decomposes to form water and gas

The product of Ammonium hydroxide decomposes into

water + ammonia gas

The product of Carbonic acid decomposes into

carbon dioxide gas + water

chemical potential energy

Energy stored in chemical bonds

Delta H

change in enthalpy

Enthalpy

Chemical potential energy that may give off or absorb as heat

delta H is negative

Products have less energy, exothermic

delta H is positive

Products have more energy than reactants endothermic

bond energy

the measure of bond strength in a chemical bond

Bond breaking

requires energy

bond formation

releases energy

activation energy

the minimum amount of energy required to start a chemical reaction

activated complex

high energy state that a reaction goes through in order to change reactants to products

thermochemical equation

Energy on reactant side is the amount of energy required to break bonds. Energy on the product is the amount of energy released

delta H equation

has delta H seperate from chemical equation.

limiting reactant

A reactant that is totally consumed during a chemical reaction, limits the extent of the reaction, and determines the amount of product.

excess reactant

the reactant that is not completely used up in a chemical reaction

If AMR\> RMR

Denominator is limiting

If AMR

Numerator is limiting

theroretical yield

the maximum possible mass of a product that can be made in a chemical reaction.

When are bonds stronger?

When there is less potential energy

when are bonds weaker?

when there is more potential energy