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Balancing Chemical Equations. Lesson 2. Balanced Chemical Equations. Balanced chemical equations show the identities and relative amounts of the substances involved in the chemical reaction. It follows the law of Conservation of Mass. Balancing Chemical Equations.
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Balancing Chemical Equations Lesson 2
Balanced Chemical Equations • Balanced chemical equations show the identities and relative amounts of the substances involved in the chemical reaction. • It follows the law of Conservation of Mass.
Balancing Chemical Equations • To balance an equation, you must find the correct number of each reactant that will react to form the balanced product. • The number used is called the coefficient • The coefficient is the number written in front of the reactant or product • It is whole number • It tells you the smallest number of particles of the substance involved in the reaction.
Steps for Balancing Equations • Write the skeleton equation for the reaction. • Count the atoms of the elements in the reactants. • Count the atoms of the elements in the products. • Change the coefficients to make the number of atoms of each element equal on both sides of the equation. • Write the coefficients in their lowest possible ratio. • Check your work.
Sample Problem • Sodium hydroxide reacts with calcium bromide to produce solid calcium hydroxide and sodium bromide. The reaction occurs in water. • NaOH (aq) + CaBr2 (aq) Ca(OH)2 (s) + NaBr (aq) • 1 Na, 1 OH, 1 Ca, 2 Br 1 Ca, 2 OH, 1 Na, 1 Br • 2 NaOH(aq) + CaBr2 (aq) Ca(OH)2 (s) + 2 NaBr (aq) • Ratio: 2:1:1:2 • Check your work