Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
Know
remaining cards
Save
0:01
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards
share
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Acids

GCSE chemistry and combined chemistry

QuestionAnswer
What does soluble mean? What does insoluble mean? Dissolves in water. Does not dissolve in water
Define acid in terms of pH A substance with a pH of less than 7
Define acids in terms of ions A substance which releases H⁺ ions in solution
State the three common acids and give their formulae Hydrochloric acid, HCl(aq), Sulphuric acid, H₂SO₄(aq), Nitric acid, HNO₃
Which ions do the common acids form in solution? HCl forms H⁺ and Cl⁻, H₂SO₄ forms 2H⁺ and SO₄²⁻, HNO₃ forms H⁺ and NO₃⁻
What is a neutral solution? A solution with a pH of 7. Water is an example.
How do you measure pH? With an indicator or pH probe.
What is a base? A metal oxide, hydroxide or carbonate that will react with an acid. E.g. copper oxide
What is an alkali? A soluble base. E.g. sodium hydroxide
Which ions are always present in a solution of an alkali? OH⁻
What is a salt? A compound formed when some or all of the hydrogen from an acid is replaced by a metal. E.g. CuSO₄, copper sulphate, where copper has replaced H from H₂SO₄
What type of salts are formed by the three main acids? Hydrochloric acid produces chlorides, sulphuric acid = sulphates, nitric acid = nitrates
What is a neutralisation reaction? Write an ionic equation for neutralisation. A reaction involving an acid that results in a neutral solution. H⁺ + OH⁻ → H₂O
Which ions always react together in a neutralization reactions between acids and alkalis? H⁺ and OH⁻
metal + acid → → salt + hydrogen gas
metal hydroxide + acid → → salt + water
metal oxide + acid → → salt + water
metal carbonate + acid → → salt + water + carbon dioxide
How do you make a soluble salt from an acid? React the acid with a base. E.g. to make copper sulphate react copper oxide with sulphuric acid
If a salt is in solution, how do you extract it as a solid? Allow the water to evaporate off and it will leave the salt behind as a solid.
What is a strong acid? An acid which completely splits up into its ions in water. E.g. when HCl is in water all the HCl molecules split up into H⁺ and Cl⁻.
What is a weak acid? An acid which will have some molecules which do not split up into their ions. E.g. in ethanoic acid only some of the molecules will have split up into the ethanoate ion and H⁺ ions.
What is the relationship between an acid of pH2 and an acid of pH 3? pH 2 is 10 times more hydrogen ions than pH 3
What is a concentrated acid? An acid where there are lots of acid particles in the water.
What is a dilute acid? An acid where there are fewer acid particles in the water.
How is pH measured? pH is related to the concentration of H⁺ in a solution.
How can hydrogen be tested for? Makes a squeaky pop when a splint is placed in it
How can carbon dioxide be tested for? Bubble through limewater, turns it milky (cloudy)
What colour is litmus in acid and alkali? Acid – red, alkali – blue
What colour is methyl orange in acid and alkali? Acid – red, alkali – yellow
What colour is phenol phthalein in acid and alkali? Acid – colourless, alkali – pink
How do you prepare a sample of a soluble salt from a base and an acid? Neutralisation, filtration, crystallisation
How do you prepare a sample of a soluble salt from an acid and an alkali? Titration, repeat titration without indicator, crystallisation
How do you prepare a sample of an insoluble salt from two solutions Combine, filtration.
Soluble or insoluble? nitrates Soluble
Soluble or insoluble? Sodium salts Soluble
Soluble or insoluble? Chloride salts Soluble, except silver and lead compounds
Soluble or insoluble? sulphates Soluble, except lead, barium and calcium compounds
Soluble or insoluble? carbonates Insoluble, except sodium, potassium and ammonium
Soluble or insoluble? hydroxides Insoluble, except sodium, potassium and ammonium
Created by: JBearfield