Notes gb lab 09 colorful chemical clues 1

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Transcript of Notes gb lab 09 colorful chemical clues 1

Notes

The student will:Distinguish between an acid and a base

The student will:Recognize indicators that can be used to help identify acids and bases

The student will:Use 4 different indicators to identify whether a substance is an acid or base

The student will:Identify “pH”Describe what pH is and how it has a meaningful effect on us

Acid BaseIndicator pH pH ScaleChemical PropertyReactivity

CombustibilityFlammability

Let’s Go!

A group of compounds which contain hydrogen and produce Hydrogen Ions (H+) when dissolved in water.

Acids taste sour, conduct electricity and corrode metals.

Acid compounds’ chemical formulas always begin with an H (a single Hydrogen atom) i.e. (HCl = Hydrochloric Acid)

A group of compounds that produce hydroxide ions in a solution.

Bases taste bitter, feel slippery, corrode metals and conduct electricity.

Base compounds always end with an OH (NH4OH) = Ammonia

A tool used to help identify wether a substance is an acid or a base

It indicates acid or base by changing color or displaying a digital reading

A symbol used to represent the percent of the Hydrogen Ion (Acid Level) in a substance.▪Ranges from 1 (Acid) – 15 (Base)

▪ One tool used with indicators that is used to indicate the strength of an acid or a base.

▪ A value of 1 indicates a strong acid▪ Battery Acid (Sulfuric Acid; H2S O4)

▪ A value of 7 represents a neutral (our blood and saliva are a pH of 7)

▪ A value of 15 represents a strong base▪ Oven Cleaner, Draino, Ammonia, Soap

A property of matter which describes the ability of a substance to create a new substance during a chemical reaction

Examples:▪Reactivity▪Combustibility▪Flammability

The tendency of a substance to undergo a chemical change either by itself or when mixed with another substance. http://www.youtube.com/watch?v=gRuoWkOlaHM http://www.youtube.com/watch?v=uixxJtJPVXk

 

Describes if a substance is capable of igniting. I.e., Gas vapors, Natural Gas

Describes if a substance is capable of burning i.e., Cloth, Rags, Paper, Wood etc.

A chemical reaction between an acid and a base which produces water and a group of compounds called “ salts”.

Now let’s tie it all together!

Acids and Bases are all around us Acids can be strong or weak having a pH value of 1 – 6, 1 being the strongest, 6 being the weakest

Strong acids can burn you; weak acids don’t 1 – HCl (Hydrochloric Acid) Strong

6 – Coffee Weak

Acids and Bases are all around us Bases can be strong or weak having a pH value ranges between 8 – 15, 8 being the weakest and 15 the strongest

Strong bases can burn you; weak Bases wontA value of 8 – 9 is weakHand soap, Detergent,

AmmoniaA value of 13 - 15 is strong. Oven Cleaner, Drain Cleaner

Something that is “Neutral” has a pH of 7. (Our bodies are neutral.)

When an acid and a base are combined a process called “Neutralization” occurs.

During neutralization the reactants (acid + base) combine to form two products..Water H2OA compound called a “Salt”

Thank you for your cooperation!

Copy and Answer these! What is “pH” and how is it measured?

What is an acid?What is a base?