Chemical reaction- one or more elements or compounds either donate, accept or share valence electrons and as a result, a new substance is formed.
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Chemists use equations to describe chemical reactions. There are two types: word equations and chemical equations.
Word Equation: hydrogen + oxygen ----> water + energy
Chemical Equation: H
2
+ O
2
----> H
2
O
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All substances on left side of the arrow are called__________. They are the substances that are used up or reacting in the reaction.
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All substances on the right side of the arrow are called_________. They are what is being created or produced as a result of the chemical reaction.
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The _______ represents that a chemical reaction is taking place.
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In this reaction, energy, is on the products side so it is being ________ from this reaction.
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Sometimes energy is on the reactants side which means it needs to be __________ from its surroundings to make the reaction happen.
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The _ sign is placed between the substances that are reacting together or being produced together.
In most chemical formulas, information about the substances ______ is also given. These are called
__________ or _______________. ex
CO
2(g) In this formula we have _____ carbon, ______ oxygen's. **Remember the 2 corresponds to the atom immediately to the left of it.
The (g) tells us that this substance is a gas, what do you think (s)_________, (l)________ or (aq)_______ mean? skeleton equation
Chemical Equation: H
2(g)
+ O
2(g)
----> H
2
O
(l)
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We will learn that in a chemical equation, the number of each atom on the left side, has to equal the number of that same atom on the right. Do they equal in this equation?
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Since they don't this type of equation is sometimes called a skeleton equation, it shows the elements or compounds but they are not balanced from the left side to the right side of an equation.
Na + LiCl ----> NaCl + Na
*the order in which the reactants are written is not important, same with the products*