Introduction To Chemistry Notes Flashcards
What is an atom?
The smallest particle of matter and is made up of protons, neutrons and electrons
What is a molecule?
Two or more atoms chemically bonded together
What is an element?
Only made up of one sort of atom. All elements are listed in the periodic table
What is a compound?
Two or more different types of atoms bounded together
What is a mixture?
Two or more different elements and/or compounds in the same space. They can be separated into individual constituents
What is the chemical formula of oxygen?
O2
What is the chemical formula of hydrogen?
H2
What is the chemical formula of nitrogen?
N2
What is the chemical formula of chlorine?
Cl2
What is the chemical formula of phosphorus?
P4
What is the chemical formula of ammonia?
NH3
What is the chemical formula of methane?
CH4
What is the chemical formula of carbon monoxide?
CO
What is the chemical formula of sulfur trioxide?
SO3
What is the formula of hydrochloric acid?
HCl
What is the chemical formula of sulphuric acid?
H2SO4
What is the chemical formula of nitric acid?
HNO3
What is the chemical formula for phosphoric acid?
H3PO4
What can transition elements do?
Form more than one stable ion
What is the chemical formula for ammonium?
NH4 +
What is the formula for a hydroxide ion?
OH -
What is the formula for a nitrate ion?
NO3 -
What is the formula for a hydrogencarbonate ion?
HCO3 -
What is the formula for a carbonate ion?
CO3 2-
What is the formula for a sulfate ion?
SO4 2-
What is the formula for a phosphate ion?
PO4 3-
How do you write the formulae of ionic compounds?
- Write the formula of the ions
- balance the charges
What is a combustion reaction?
Burning a substance in oxygen
What is the equation for the combustion of methane?
CH4 + 2O2 ~ > CO2 + 2H2O
What is a decomposition reaction?
When a substance breaks down to form two or more substances.
What is the equation for the decomposition of calcium carbonate?
CaCO3 -> CaO + CO2
What is a neutralisation reaction?
The reaction between an acid and a base to form water
What are the products of a neutralisation reaction?
A salt and water
What is a redox reaction?
Where reduction (gain of electrons) and oxidation (loss of electrons) takes place
What is an exothermic reaction?
A reaction that releases heat energy to the surroundings
Do the products or the reactants have more energy in an exothermic reaction?
Reactants have more energy
What is an endothermic reaction?
A reaction that takes in heat from the surroundings
Do the products it the reactants have more end in an endothermic reaction?
Products have more energy
What is a reversible reaction?
Reactants can form products and products can form reactants
What is an acid?
A substance that donates
What is the formula for ethanoic acid?
CH3COOH
What is a base?
A substance that donates H+ ions
What are some common bases?
Metal oxides, metal hydroxides, ammonia
What is an alkali?
A base that releases hydroxide ions in aqueous solution
What is the chemical formula of sodium hydroxide?
NaOH
What is the chemical formula for potassium hydroxide?
KOH
What is the chemical formula for barium hydroxide?
Br(OH)2
What is the chemical formula for aqueous ammonia?
NH3(aq) / NH4OH
What is an amphotenic substance?
It can be an acid and a base
What is a salt?
Is formed when the hydrogen ions from an acid are replaced by a metal or ammonium ion
What are chloride salts formed from?
Hydrochloric acid
What are sulfates formed from?
Sulfuric acid
What are nitrates formed from?
Nitric acid
What are phosphates formed from?
Phosphoric acid
What acid was used to make MgSO4?
H2SO4
What acid was used to make Ca3(PO4)2?
H3PO4
What is the formula of the acid that made NH4NO3?
HNO3
Acid + alkali -> ?
Salt + water
Acid + base -> ?
Salt + water
Acid + metal -> ?
Salt + hydrogen
When is the only time hydrogen is a product?
When an acid reacts with a metal
Acid + metal carbonate -> ?
Salt + water + carbon dioxide
Acid + metal hydrogencarbonate
->
Salt + water + carbon dioxide
What happens when an ionic substance dissolves in water?
The positive and negative ions separate and become hydrated
What are the three steps in writing ionic equations?
- Aqueous ionic compounds are written as separate ions
- solid, liquid, gases and covalent aqueous compound are unchanged
- cancel ions that appear on both sides of the equation