Formulas, Reactions & pH Flashcards
What is an acid?
Either:
- Substances which want to donate one or more Hydrogen ions (aka protons), H+
- Substances which are capable of forming a covalent bond with an electron pair.
What is a Base?
A substance that react with solutions containing Hydrogen ions
What are the products of this reaction?
Carbonate + acid →
Salt + water + carbon dioxide
What are the products of this reaction?
Hydrogen carbonate + acid →
Salt + water + carbon dioxide
What is the difference between a base and an alkali?
A base that dissolves in water is an alkali.
What is the pH of Alkali solutions?
pH > 7
Which ion do Alkalis solutions have?
Hydroxide ion, OH-
What is an Alkali?
A Base that can be dissolved in water.
What pH range would you expect a weak alkali to be in?
pH 10 - 11
What pH range would you expect a strong alkali to be in?
pH 13 - 14
What is the pH scale used to measure?
The relative acidity or alkalinity of a solution
What is the numeric range of the pH scale?
0 - 14
How would you describe a solution with a pH of 2?
Strong acid
How would you describe a solution with a pH of 4?
Weak acid
How would you describe a solution with a pH of 8?
Weak alkali
How would you describe a solution with a pH of 13?
Strong alkali
How would you describe a solution with a pH of 7?
Neutral
What is neutralization?
The mixing of an acid and alkali (or visa versa) until the solution becomes neutral (pH of 7).
List four properties of Acids
pH of < 7
Taste sour
Are corrosive
Contain Hydrogen ions, H+
What are the products of this reactions?
acid + metal →
Salt + hydrogen
What are the products of this reactions?
acid + base →
Salt + water
What gas is present when lime water turns cloudy as the gas passes through it?
Carbon dioxide, CO2
What gas is present when a glowing splint reignites when put into a test tube?
Oxygen, O2
How many protons does Aluminium have?
13
What are indicators used for in Chemistry?
Test solutions to show if they are acidic, neutral or alkaline
What colour is Red Litmus go when testing an acid?
Red
What colour is Red Litmus go when testing an alkali?
Blue
What colour is Blue Litmus go when testing an acid?
Red
What colour is Blue Litmus go when testing an alkali?
Blue
What colour is Red Litmus go when testing a neutral solution?
Red
What colour is Blue Litmus go when testing a neutral solution?
Blue
What is the colour range of Universal Indicators?
Red for acid through to Purple for Alkali
What are all metal oxide and metal hydroxides?
They are all Bases
What is the chemical formula for Hydrochloric acid?
HCl
What is the chemical formula for Sulfuric Acid?
H2SO4
What is the chemical formula for nitric acid?
HNO3
What is the chemical formula for zinc sulfate?
ZnSO4
What is the chemical formula for water?
H2O
What is the chemical formula for sodium carbonate?
NaHCO3
What is the chemical formula for copper hydroxide?
Cu(OH)2
What is the chemical formula for aluminium oxide?
Al2O3
What is the chemical formula for carbon dioxide?
CO2
What an OH- ion?
Hydroxide ion
What is a HCO3- ion?
Hydrogen carbonate ion
What is a NO3- ion?
Nitrate ion
What is a SO4^2- ion?
Sulfate ion
What must be remembered about charges when writing the formula for a substance?
+ charges must equal - charges
Explain why alkalis are different from Bases
Alkalis are made of those Bases which are soluble in water.
What numbers must be the same of each side of a chemical equation?
The number of atoms
How can you increase the number of atoms when balancing an equation?
By putting a number in front of the reactant or product. (coefficient)
What are reactants?
Substances that are brought together to create a chemical reaction.
What are products?
Substances formed by a chemical reaction.
What must never be changed in chemical reactions?
The formulae of the reactants or products.
When this reaction, hydrogen carbonate + acid → , occurs how can you tell a gas is produced?
There is a fizz, gas bubbles can be seen in the liquid.
What needs to be present along with Bicarbonate of Soda (Baking soda) for the Baking to rise?
An acid
How many Groups are there in the Periodic table?
18
What do elements in the same Group have in common?
Similar configurations of electrons in their valence shell.
What is a mixture?
A substance where two or more element or compounds are combined physically but not chemically bonded to each other.