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pH. “Power of Hydrogen”. Water and pH. Acids: When poured into water, it gives up H (hydrogen) to the water. Bases: When a base is poured into water, it gives up OH (hydroxide) to the water. For Example….
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pH “Power of Hydrogen”
Water and pH • Acids: When poured into water, it gives up H (hydrogen) to the water. • Bases: When a base is poured into water, it gives up OH (hydroxide) to the water
For Example….. Acids -When hydrochloric acid (HCl) mixes with water, it separates into positive hydrogen (H+) and negative chlorine (Cl-). H+ = ACID
Characteristics of Acids:Acids taste sourAcids react strongly with metals (Zn + HCl)Strong Acids are dangerous and can burn your skin • Examples of Acids:1. Vinegar 2. Stomach Acid (HCl)3. Citrus Fruits
Bases When the base sodium hydroxide/ (NaOH) “Bleach” mixes with water, it separates into positive sodium (Na+) and negative hydroxide (OH-). OH- = Base What must Neutral mean?
Solutions containing bases are often called alkaline • Characteristics of Bases:Bases taste bitterBases feel slipperyStrong bases are very dangerous and can burn your skin • Examples:1. lye (Sodium Hydroxide)2. Ammonia
pH Scale Runs from 0-14 0-6 is an ACID 8-14 is a BASE 7 is NUETRAL
Where do the numbers come from? • The pH scale is logarithmic • One unit change in pH is a 10-fold change pH = - log [H+] • If [H+] = 1 X 10 -7, the negative log of [H+] = 7, therefore pH=7