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Acids and BasesI can compare/contrast the properties of acids, bases, and neutralsolutions.

I can identify a substance as acidic, basic, or neutral given its pH.I can use indicators to determine whether a substance is acidic, basic, orneutral.

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Acids

any compound that increases the number of

hydronium ions - H3O+, when dissolved in

water hydronium ions form when a hydrogen ion separates

from the acid and bonds with a water molecule

properties of acids sour taste changes color of substances corrosive most are poisonous

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Indicators of Acids

indicator - a substance that changes colorin the presence of an acid or base bromthymol blue - pale blue in water, turns yellow

with acid litmus - paper strips that changes color when

touching acid or base

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More Acid Info...

Acids react with metals and give offhydrogen gas 2 HCl + Zn --> H

2+ ZnCl

2

Acids conduct electricity acids dissolve in water and form ions - batteries

Common Acids sulfuric acid - most widely used acid in industry

nitric acid - fertilizer, rubber, plastic hydrochloric acid - refine metals, clean algae from

pools, stomach Citric, Ascorbic (vitamin C), Carbonic

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Bases

Any compound that increases the number of

hydroxide ions - OH-, when dissolved inwater NaOH --> Na+ + OH-

hydroxide ions give bases their properties

properties bitter taste

slippery feel many are corrosive

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Examples of Bases

soap - sodium hydroxide bleach, detergents baking soda - toothpaste, mouthwash

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Indicators of Bases

indicator - a substance that changes colorin the presence of an acid or base bromthymol blue - pale blue in water, turns darker

blue in base litmus paper change colors

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More Base info...

bases conduct electricty OH- is a negative ion and helps with electrical

current

uses of bases sodium hydroxide - soaps, paper, oven cleaners,

drains calcium hydroxide - cement, plaster ammonia - cleaners, fertilizers aluminum hydroxide - antacids

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Strong Acids, Weak Acids

an acid's strength is determined by howmany hydrogen ions are created when itreacts with water strong acids - all of the molecules of the acid break

down and form many ions sulfuric, nitric, hydrochloric

weak acids - few molecules of the acid break down

and form ions acetic, citric, carbonic

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Strong Bases, Weak Bases

base's strength determined by how many

OH- (hydroxide) ions are created with water strong base - all the molecules of base form ions

sodium hydroxide, calcium hydroxide weak base - few molecules form ions

ammonium hydroxide, aluminum hydroxide

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Neutralization Reactions

acids and bases can react to neutralizethemselves hydrogen ions from acids react with hydroxide ions

from bases to form water, which is neutral H+ + OH- --> H

2O

other ions from the acids and bases can combine tomake salts

Antacids - eating an antacid (a base) willreact and neutralize stomach acid

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pH Scale

litmus paper uses the pH scale as anindicator of acids and bases describes how acidic or basic a solution is

pH - measure of the hydronium ionconcentration in a solution scale measures from 0-14 ph of 7 is neutral - pure water

bases have pH higher than 7 acids have pH less than 7 p. 375 has a good pH scale

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pH Scale