1.1 balancing chemical equations

chemistry

what is a balanced equation

A balanced equation is a symbol equation in which there are equal numbers of each atom on either side of the equation

what is a word equation

a word equation is an equation in which the reactants and products in a chemical reaction are represented by words

when balancing a chemical equations, are you allowed to change the small numbers such as the 2 in N2

No, you can only change the large numbers in front

what is a reactant

reactants are the starting chemicals in a chemical reaction

what is a product?

products are the new substances produced by a chemical reaction

whats the state symbol for a solid

(s)

whats the state symbol for a liquid

(l)

whats the state symbol for a gas

(g)

whats the state symbol for a aqueous solution

(aq)

what state symbol is for a dilute acid

(aq)

why is (aq) used for dilute acids and not (l)

• acids are dissolved in pure water

• therefore they are not pure liquids

what elements exist as diatomic molecules (have no fear of ice cold bear)

H₂ N₂ O₂ F₂ Br₂ I₂

what state is hydrogen in reactions

gas —— H_{2 (g)}

hydrochloric acid

HCl (aq)

Nitric acid

HNO₃

Sulfuric acid

H₂SO₄

Sodium hydroxide

NaOH (aq)

Carbon dioxide

CO₂

water

H₂O

why must equations be balanced

• atoms cannot be created or destroyed, so the number of each atom must be the same on both side

• atoms in the reactants are rearranged to form the products

• conservation of mass

metal + acid —→

salt + hydrogen