Acids and alkali Flashcards
Formula Sodium Hydroxide
NaOH
Formula Magnesium Hydroxide
Mg(OH)2
What type of elements makes acid?
non-metals
Formula for hydrochloric acid
HCl
Formula Nitric acid
HNO3
Formula for sulfuric acid
H2SO4
Formula for Lithium Oxide
Li2O
Is Calcium oxide an acid, base or alkali?
alkali
what is the difference between an alkali and a base?
An alkali is a soluble base. (all alkali are bases but not all bases are alkali)
What soluble mean?
It can dissolve in water
What page in the databook can I find if a substance is soluble in water or not?
page 8
What would be the pH of water if we added carbon dioxide
acidic
What would be the pH of water if we added Silicon dioxide
neutral (silicon dioxide doesn’t dissolve in water)
What would be the pH of water if we added Copper(II) oxide?
neutral, copper (II) oxide is insoluble in water.
What would be the pH of water if we added phosporous oxide
acidic
What would be the pH of water if we added potassium oxide
alkali
What is a solute?
a solid (eg. SALT)
What is a solvent ?
A liquid (eg: Water)
What is a solution?
When a solute disolve in a solvent (eg: sea water)
What does saturated mean?
Too much solute / when the solute stop dissolving in the solution
What is a precipitate
A soluble substance appears in solution
What is the pH of acids?
Less than 7
What is the pH of water/ neutral solution?
pH of exactly 7
What is the pH of a base/ alkali?
pH more than 7
What is the pH scale a measure of?
The concentration of hydrogen ions (H+) in any given solution
How can the pH be measured?
pH meter
pH indicator
pH paper
What is the name of OH-
Hydroxide ions
What is the name for H+
Hydrogen ions
In pure water what is the concentration of H+ and OH- ions?
Hydrogen ions = hydroxide ions
What ion does all acids contain?
H+ / Hydrogen ions
Why do acidic and alkaline solutions conduct electricity well?
They contain oppositely charged ions that are free to move in solution and can carry charge
What is the proportion of hydroxide and hydrogen ions in alkaline solution ?
More OH- than H+
What happens to the pH and the concentration of an acid when you dilute it?
The pH goes up and concentration of the acid goes down
What happens to the pH and the concentration of an alkali when you dilute it?
The pH goes down and concentration of the alkali goes down
If a metal oxide is soluble in water what does it produce ?
An alkali
If a non metal oxide is soluble in water what does it produce
An acid
What does acids contain?
Charged particles called hydrogen ions
what is the difference between a base and an alkali
A base is a substance that neutralises an acid
A base that is soluble in an alkali
All alkalis are bases but not all bases are alkalis
What is a spectator ion?
It’s an ion that exists in the same form on both the reactant and product sides of a chemical reaction
what is titration?
an experimental method to determine the concentration of an unknown solution.
How to recognise hydrogen? (test for hydrogen?)
Burns with a pop
How to recognise oxygen? (test for oxygen)
Relights a glowing splint
How to recognise carbon dioxide? (test for carbon dioxide)
Turns lime water cloudy
What is the name of a metal oxide that do not dissolve in water but is capable of neutralising an acid?
a base
What are the products of this reaction: Hydrochloric acid + potassium carbonate?
potassium chloride + water + carbon dioxide
What are the products for this reaction:
Sulfuric acid + Lithium oxide? (write the chemical formula for the salt produced)
Lithium sulfate + water
Salt: Lithium Sulfate, formula: Li2SO4
What is the formula for Sodium carbonate?
Na2CO3
Formula for Sodium hydroxide (Alkali)
NaOH
Write the chemical equation for the neutralisation reaction between Magnesium oxide and Nitric acid
MgO + HNO3 –> Mg(NO3)2 + H2O
H2SO4 + 2NaOH
If 20ml of acid of concentration 0.2 mol/l were used to neutralised 25ml sodium hydroxide, what is the concentration of sodium hydroxide?
H2SO4 + 2NaOH
n=0.004 n=0.008
C=0.2 V=0.025
V=0.02 C= 0.32
Concentration of NaOH=0.32mol/l