ACID & BASE SOLUTIONS

Learning Scale: 4 Investigate and describe the compounds formed by bonding elements. 3 Describe how elements combine to form compounds. Describe the motion of the particles in a solid, liquid, and gas. Explain how groups of elements are similar to each other. 2 Use the periodic table to identify the number of protons, neutrons, or electrons in an element. Describe the structure of an atom. 1 Locate and identify elements on the periodic table.

What are acids? An acid is a substance that produces a hydronium ion (H3O+) when placed in water. Examples of Acids:

Properties of Acids Sour Taste Can damage skin and eyes Corrosive – react with metals Conduct electricity

What are bases? A base is a substance that produces hydroxide ions (OH-) when dissolved in water. Examples:

Properties of Bases Bitter Taste Can damage skin and eyes Slippery when mixed with water Conduct electricity

What happens when acids & bases combine? A salt forms when the negative ions from an acid combine with the positive ions from a base. Neutralization – when the acid and base cancel each other out

What is the pH scale? The pH scale is used to indicate how acidic or basic a solution is. A change in one pH unit represents a tenfold change. For example a pH of 1 is ten times stronger than a pH of 2.

Acids are less than 7 Bases are greater than 7

How is pH measured? An indicator is a compound that changes color at different pH values when it reacts with acidic or basic solutions. pH testing strips pH meters

Learning Scale: 4 Investigate and describe the compounds formed by bonding elements. 3 Describe how elements combine to form compounds. Describe the motion of the particles in a solid, liquid, and gas. Explain how groups of elements are similar to each other. 2 Use the periodic table to identify the number of protons, neutrons, or electrons in an element. Describe the structure of an atom. 1 Locate and identify elements on the periodic table.