acids and bases an introduction if you forgot, and review if you remember!
TRANSCRIPT
Acids and BasesAn introduction if you forgot, and
review if you remember!
Acids and Bases
O Acids and Bases Video
O Note: you DO NOT need to know the pH math formula part!!!
Acids and Bases WSO Read through the information on the
first page to learn about acids and bases
O Once you’ve read through it, turn the page over and work through the Acids and Bases quiz
O When you are finished, read pg. 223-224 in your text book
O When you are finished, answer the Reading Check questions on pg. 225
Acids, Bases and Neutral
O Acids are chemical compounds with a pH of LESS THAN 7
O Bases are chemical compounds with a pH of MORE THAN 7
O pH of 7 are NEUTRAL (neither acidic nor basic)
Examples of Acids
O Stomach acid
O Citrus fruits
O VinegarO Car
batteriesO Acid rain
Examples of BasesO BloodO Baking
SodaO DranoO Egg
WhitesO BleachO Soap
Properties of Acids and Bases
ACIDS BASES
- pH less than 7- Sour taste- Corrosive- Turns blue litmus red- Contains hydrogen ions
(H+)- Usually has an H at the
left side of the formula- Neutralizes bases to form
a salt and water
- pH greater than 7- Bitter taste- Slippery, soapy and
corrosive- Turns red litmus blue- Contains hydroxide ions
(OH-)- Usually has an OH at the
right side of the formula- Neutralizes acids to form
a salt and water
Identifying Acids 101O Acids have hydrogen (H+) ions in
them, and are usually found at the far left of the formula
O Example: HCl, H2SO4, HNO3, etc.
Identifying Bases 101O Bases have hydroxide (OH-) ions in
them, and are usually found at the far right side of the formulaO Example: NaOH, Mg(OH)2, Ca(OH)2,
etc.
Warning!!!O Some
acids/bases are corrosive (can burn through things)
O You should NEVER test whether a solution is an acid or base by tasting or touching
But seriously don’t…
The Safe Way!O pH indicators are chemicals that
change colours, depending on the pH of the solution they were placed in
Examples:O Litmus paperO Methyl OrangeO Bromothymol BlueO PhenophthaleinO Indigo CarmineO Magnesium Ribbons
pH IndicatorsThese indicators change color, depending on what they are put in:
PracticeO What colour is litmus paper in an
acidic solution?O What colour is bromothymol blue at
a pH of 5? 7? 9?O Is a solution an acid or a base if you
add methyl orange and it turns yellow?
O Is a solution an acid or a base if you add phenolphthalein and it’s colourless?
Lab tomorrow!O Read the pH indicators lab and be
prepared to perform this lab tomorrow.
O O DO NOT LOSE, FORGET, or DESTROY
this lab. It is the only copy you will get and if you do lose, forget or destroy it, you will have to write it all out BY HAND!