Acids and Alkalis Flashcards
revise (26 cards)
What are the 3 things that define a solution?
-acidic
-alkaline
-neutral
What colour to acids turn after being mixed with universal indicator?
-warm colours
-red ph1
-orange ph2+3
-yellow ph4
-pale green ph5+6
What colour to alkalis turn after being mixed with universal indicator?
-cold colours
-turquoise ph9
-light blue ph10
-dark blue ph11+ph12
-dark purple+blue ph13+ph14
What colour to neutral solutions turn after being mixed with universal indicator?
-GREEN ph7
True or False, alkaline solutions are more salty than acidic solutions.
True.
Alkaline solutions are really salty.
What is a substance that is a pH scale of 7?
pure water
What is a substance that is a pH scale of 10?
great salt lake
milk of magnesia
What does exothermic mean?
That heat has been given out by the reaction. This is shown by there being an increase in temperature of the products.
What is the opposite of exothermic?
endothermic
How does a wasp sting be reduced by adding vinegar?
The acidity of the vinegar can help neutralize the basicity of wasp stings.
Why are lakes in the world have lime added to them?
The lime is put there to neutralize acid waters and soils.
Why is toothpaste slightly alkaline?
To neutralize the acidic effect of food on our teeth we brush our teeth with toothpaste.
How can you take tablets to reduce effects of heart burn?
The tablets are antacids and they work by neutralizing the stomach acid that causes heartburn.
What does excess mean?
Excess means to add too much. This is done to ensure that all of the acid has reacted.
What gas is produced when calcium carbonate reacts with acid?
carbon dioxide
How do you make red cabbage indicator?
Chop up cabbage and leave in a beaker of boiling water. The colour turns purple with the pigment leaching out of the cabbage.
What colour does the indicator universal indicator turn to?
when mixed with-
-acid- red
-neutral- green
-alkaline- dark purple/blue
How do you use universal indicator to measure pH values?
Add equal drops of universal indicator to your substances. Compare it to the ph chart and match the colour of the value.
What happens when a substance is diluted with water?
If a substance is diluted with water, then its acidity/alkaline goes down a bit (increases/decreases)
How does the pH chart work?
1= increasingly acidic
7= neutral
14= increasingly alkaline
How do you know when a solution is neutral?
When the universal indicator turns green.
How to rank acid solutions in order of acidity?
Add small amounts of alkali to solutions, the more alkali required the stronger the acid was.
How can you neutralize something?
Add more acid to alkali
Add more alkali to acid
UNTIL GREEN AND NEUTRAL
What are indicators?
Tell the difference between acidic, alkaline and neutral solutions.
e.g- universal indicators
