| A | B |
|---|
| chemical reaction | process in which substances undergo chmical and physical changes that result in formation of new substances with different properties |
| reactant | substance that enters into a chemical reaction |
| product | substance produced by a chemical reaction |
| chemical equation | expression which are used to represent the chemical reactions |
| synthesis reaction | chemical reaction in which two or more simple substances that combine to form a new more complex substance |
| decomposition reaction | chemical reaction in which a simplex substance breaks down into two or more simpler substances |
| single-replacement reaction | chemical reaction in which an uncombined element replaces an element that is part of a compound |
| double replacement reaction | chemical reaction in which different ions of two different compounds replace each other |
| exothermic reaction | chemical reaction in which heat is released |
| endothermic reaction | chemical reaction in which heat is related |
| activated complex | highly unstable structure formed when reactants combine and are rearranged to form products |
| exergonic reaction | chemical reaction that occures easily; a spontaneous reaction |
| endergonic reaction | a chemical reaction that is not spontaneous |
| kinetics | study of rates of chemical reactions |
| reaction rate | measure of how quickly reactants change into produce |
| collision theory | theory that relates collisions among particles and the reaction rate; the reaction rate depends on such factors as concentration surface area |
| catalyst | substance that increase the rate of chmical reaction with out being changed |
| Why do substances react chemically? | substaces react because of the level of concertration and heat energy absored or released |
| Describe what a chemical equation is | expresions in which numbers formuls are use to reprsent a chmical reaction |
| State the law of conservation of mass and explain its role in chemical equations. | ; mass remains constant and is never lost; the observatio that mass remains constant in a chemical reaction |
| What is a coefficient? | a coeficient is the number in front of a formul |
| What is the difference between H2O2 and 2H2O? | two or more substances that are combined to make a new complex substance |
| Describe each of the four types of chemical reactions. Include an equation showing the general form for each. | synthesis reaction; double replacement, single replacement and decomposition; synthesis is two or more simple substances combine to make a new more complex substance a+b=cdecomposition is a substance that breaks down into two or more simpler substace c=a+b single replacement an uncombined element that replaces an element that is already part of a compound a+BX=AX+B doudle replacement different ions in two fifferent compounds replace each other AX+BY=AY+BX |
| How can the energy from an activated complex be affected by a catalyst? | catalysts can change the rate of reaction and it produces a different lower energy pathe for the reaction |
| Explain how the energy content of the products of a reaction compares with that of the reactants when the reaction is exothermic | Reactants must climb to the top of the energy hill to form an activated complex. Energy is released as the products form. |
| Use the collision theory to explain the effects on reaction rate of increased concentration, catalysts, and increased surface area. | surface aear the reaction in the solid can be increased by breaking down the solid in to smaller pieces the collision is increased between the reacting particals catalyts increase the chemical reaction concertratio the more produtes are formed in a certain amout of time |
| Give two reasons why collisions between molecules of reactants may not be effective in forming products. | the substances that enter the chemical reaction is the reactant once the reactant enter the chemical formula the molecules are already affeted in the products |
| In a balanced chemical equation | xx |
| Two or more substances combine to form | a new more complex substances synthesi reaction |
| In an endothermic reaction, heat is | heat is taken into a reacting chemical sudstances and becomes chemical enery in the produts of reaction |
| The energy required for reactants to form products is called | active energy |
| The substances to the left of the arrow in a chemical equation are called | coeffciebts |
| An atom's ability to undergo chemcial reactions is determined by | outermost electrons |
| The rate of a chemical reaction can be increased by | incresing surface area |
| Adding a catalyst to a reaction increases its rate by | lowering activation energy |
| The substances formed as a result of chemical reaction are called | product |
| A number written in front of a chemical symbol or formula is a | coefficient |
| In a ____ reaction, complex substances from simpler substances. | decompositon reaction |
| The formation of carbon dioxide during combustion of a fuel is anexample fo _____ reaction. | xx |
| In a exothermic reactions, products have ____ energy than reactants. | xx |
| The study of rates of chemical reaction is ____ | kinestics |
| The ___theory can be used to account for the factors that affect reaction rates. | yes collision theory |
| therm means | heat |
| ex means | go away from or release |
| en means | in or within |
| What is the relationship between the arrangement of electrons in an atom and the atom's chemical properties? | The arrangement of electrons in an atom determines the ease with which the atom will form chemical bonds. |
| Why must a chemical equation be balanced? | the numer of atoms of each element must be the same on both sides of the equation |
| Explain why you can't change symbols, formulas, or subscripts in order to balance a chemical equation | Changing the subscript would mean changing the substance; changing a formula would change the entire chemical equation; changing a symbol would change the the whole element |
| On which side should the energy term be written in an equationrepresenting an endothermic reaction? | xx |
| endo means | into |
| How is the reaction rate related to the collision theory? | It all depends on how fast the particles collide |
| How does collision theory explain the effect of a decrease in temperature on the reaction rate? | an increase in temperature is an increase in the rate of a reaction |
