Chapter 5 Flashcards
What is the test for carbon dioxide?
It turns limewater cloudy
A reaction between an acid and an alkali is called?
Neutralization
What are the products of a reaction between an acid and a metal oxide or metal hydroxide?
A salt and water
What are the products of a reaction between an acid and a metal?
A salt and hydrogen
How do you name a salt?
Put the metal first and then the acid ending
- sulfuric acid gives metal sulphates
- nitric acid gives metal nitrates
- hydrochloric acid gives metal chlorides
How do you define an alkali?
By their OH- ions
How do you define an acid?
By their H+ ions
What is the ionic equation for neutralisation?
H+ + OH- ———-> H2O
What are the products of a reaction between an acid and a metal carbonate?
A salt and water and carbon dioxide
Name and give the formula of three acids.
- sulfuric acid (H2SO4)
- nitric acid (HNO3)
- hydrochloric acid (HCl)
Note: put your hand over the H and what is left is the ending to your salt
pH is a measure of……
… the concentration of H+ ions
Acids have a pH………
below 7 - yellow/red
Alkalis have a pH…………..
above 7 - blue/purple
Why is a pH meter better than universal indicator to measure the pH of a substance?
It is more accurate
What is the pH of a neutral substance?
7 - green
What are indicators?
A substance that changes colour to show the point of neutralisation or the pH of a substance
e.g. universal indicator, litmus paper
What is a displacement reaction?
It is a reaction where a more reactive metal displaces a less reactive metal
e.g zinc + iron oxide —–> zinc oxide + iron
What is the reactivity series?
It is the order in which metals are placed based on their reactivity. More reactive metals are placed at the top.
Definition of an acid.
A substance that can attack metal, clothing or the skin. Has a pH of less than 7. They are proton (H+ ion) donators.
What is a burette?
A long glass tube with a tap at one end and markings to show volumes of liquid. Used to add precisely known amounts of liquids to a solution in a conical flask below it. It is used to measure variable accurate volumes of liquids.
What do we mean by the term precipitate?
An insoluble solid formed by a reaction taking place in solution. (Some salts are insoluble)
What is a pipette?
A tube used to measure a fixed accurate volume of liquid.
What is an ore?
Rock which contains enough metal to make it economically worthwhile to extract the metal.
What is a weak acid? (H)
Acids that do not deionise completely so only produce a few H+ ions
What is a strong acid? (H)
Acids that deionise completely to produce H+ ions
What is a dependent variable?
One that you measure
What is a control variable?
One that you must keep the same
What is an independent variable?
One that you change
What does valid mean?
You have used a suitable method and equipment to get an answer (data) to your question
What does reproducible mean?
A measurement is reproducible if SOMEONE else can do the experiment and get the same results
What does repeatable mean?
A measurement is repeatable if YOU can do the experiment again and get the same results
What is qualitative date?
Descriptive date such as eye colour
What is quantitative data?
Data that is numerical e.g. a measurement
What is thermal decomposition?
The breakdown of a compound by heating
What is the charge on these polyatomic ions?
- Hydroxide ion OH
- Sulphate ion SO4
- Nitrate ion NO3
- Carbonate ion CO3
- OH-
- SO4 2-
- NO3 -
- CO3 2-
Why is a pH curve used?
To give a more accurate measure of the exact volumes of acids and alkalis need for neutralisation
What is the name of this piece of equipment?
Conical flask
What is the name of this piece of equipment?
volumetric flask
What is the meniscu?
The curved upper surface of a liquid in a tube or cylinder
Remember we always measure from the bottom of the meniscus
