Chemistry Unit 2

Synthesis Reactions

A reaction where two or more reactants combine to form a new product.

Types of Synthesis Reactions

1. Two elements form an Ionic Compound, 2. Two Elements form a Covalent Compound, 3. Two Compounds form a New Compound.

Ionic Compound

Formed when a univalent metal reacts with a non-metal.

Univalent Metals

Metals that have a single ionic charge.

Multivalent Metals

Metals that have more than one ion charge, making it difficult to predict products in synthesis reactions.

States of Matter for Products/Reactants

Ionic compounds are usually solid or aqueous, while nonmetals are typically gases.

General Rules for Predicting Products

You need to predict the products and balance all equations in synthesis reactions.

Decomposition Reactions

A reaction where a compound breaks down into two or more products.

Types of Decomposition Reactions

1. Binary compound decomposes into elements, 2. Metal nitrate decomposes into metal nitrite and oxygen gas, 3. Metal carbonate decomposes into metal oxide and carbon dioxide, 4. Metal hydroxide decomposes into metal oxide and water.

Binary Compound Decomposition

Binary compounds can decompose into elements using heat or electricity.

Heat in Decomposition

Indicated by the delta (∆) symbol, meaning heat is added to the reaction.

Electricity in Decomposition

Indicated by the word 'Electricity' placed above or below an arrow in a reaction.

Metal Hydroxide Decomposition

Decomposes into metal oxide and water.

Chemical Equation Example: Na + Cl

2Na(s) + Cl2(g) -> 2NaCl(s) illustrates the formation of an ionic compound.

Predictions in Synthesis Reactions

You must predict the products based on the reactants used.

Testing for Covalent Compounds

When two non-metals react, the ratio of elements must be determined experimentally.

Example of Covalent Compound Formation

C(s) + O2(g) -> CO2(g) is an example of two nonmetals forming a covalent compound.

Formation of Acid from Non-metal Oxide

A non-metal oxide can react with water to form an acid.

Metal Oxide and Water Reaction

Metal oxide reacts with water to produce a base.