Chemical Reactions Flashcards
What does this symbol mean?
Environmental hazard
What precaution should you take if a chemical contains this symbol?
Environmental hazard - careful disposal is required. Do not place down the sink.
What does this symbol mean?
Toxic
If you spill some toxic or corrosive chemicals what should you do?
Clean up immediately and wash hands thoroughly.
What does this symbol mean?
Corrosive
What does this symbol mean?
Explosive
What does this symbol mean?
Irritant
What does this symbol mean?
Flammable
What precaution should you take with flammable chemicals
Keep away from heat, fire and sparks. No naked flames.
What is this symbol?
Oxidiser
What is this symbol?
Respiratory irritant
True or False - Acids are always corrosive?
False. Acids can be irritants or non-hazardous
True or False - Acids are more dangerous than alkalis?
False.
When handling irritants what precautions should you take?
Wear safety glasses. Wash spills immediately.
What colour do acids turn litmus?
Red
What colour do alkalis turn litmus?
Blue
What colour do neutral solutions turn litmus?
Purple
Is water acid, alkali or neutral?
neutral
Give 3 examples of acids found in everyday life.
Fizzy drinks, vinegar, juice, battery acid
Give 3 examples of alkalis found in everyday life.
Toothpaste, washing powder, hair dye, drain cleaner, bleach
What colour will universal indicator be in acids
Red (strong acids) orange or yellow (weaker acids)
What is the pH of a strong acid
0 or 1
What is the pH of a neutral solution
7
What is the pH of an acid?
<7
What is the pH of an alkali?
> 7
What is the pH of a strong alkali?
14
What colour will universal indicator be in alkalis?
Blue or purple
What colour will universal indicator be in neutral solutions?
Green
What colour is red cabbage indicator in neutral solutions?
Purple
What colour is red cabbage indicator in acids?
Red or pink
What colour is red cabbage indicator in alkaline solutions?
Green
Which element do all acids contain?
Hydrogen
What contains hydroxide ions?
Alkaline solutions
What reaction occurs if we add an acid to an alkali?
Neutralisation
When naming salts, sulfuric acid will form a….?
________ sulfate
(the blank space would be the metal from the alkali e.g. copper sulfate)
When naming salts, hydrochloric acid will form a….?
__________ chloride
(the blank space would be the metal from the alkali e.g. sodium chloride)
When naming salts, phosphoric acid will form a….?
____________ phosphate
(the blank space would be the metal from the alkali e.g. calcium phosphate)
When naming salts, nitric acid will form a….?
____________ nitrate
(the blank space would be the metal from the alkali e.g. copper nitrate)
When naming salts, ethanoic acid will form a….?
___________ ethanoate
(the blank space would be the metal from the alkali e.g. sodium ethanoate)
Sodium hydroxide makes what kind of salts?
Sodium
e.g. sodium chloride
Potassium hydroxide makes potassium salts
Potassium
e.g. potassium chloride
Acid + alkali -> ______ + ______
Salt + water
What is a base?
Any substance that neutralises an acid forming salt + water
Is an alkali a base?
Yes! It is a soluble base
Why are insoluble bases usually preferred to alkalis where neutralisation is required? e.g. indigestion tablets, soil pH adjustment
If too much alkali is added it will dissolve and make an alkaline solution. If too much insoluble base is added, the substance remains neutral because it does not dissolve.
Give some typical properties of metals
Strong, high melting point, good conductor of heat and electricity, shiny when polished.
metal + acid ->
Salt + Hydrogen
(remember MASH!)
How do we test for hydrogen?
Squeaky pop with a lit splint
How do we test for carbon dioxide?
Turns limewater cloudy
How do we test for oxygen?
Relights a glowing splint
metal carbonate + acid ->
salt + water + carbon dioxide
What do you call a mixture if the solid settles out of the liquid if left to stand still?
Suspension
What do you call a cloudy mixture where the solid does not settle out of the liquid if left to stand still?
Colloid
What do you can a mixture where the solid is dissolved in a liquid
Solution
What is a solution?
A mixture where a solid dissolves into a liquid
Which “s” describes something that will dissolve in a liquid
Soluble
Which word describes something that won’t dissolve in a liquid
Insoluble
When a solution contains the maximum amount of liquid that will dissolve in it, this is known as
Saturated
What is solubility?
The amount of a substance that will dissolve in a given amount of liquid
What do you call the substance that will dissolve in a liquid to make a solution
Solute
What do you call a liquid into which other substances will dissolve
Solvent
When a substance is dissolved in a liquid what happens to the overall mass?
Stays the same. Nothing “disappears” - you have the same number of atoms before and after.
What happens to solubility as temperature increases?
It increases
