M2 - Compounds, formulae, equations and acids Flashcards
Atomic structure and isotopes, Relative mass and Formulae and equations
What is an ion?
A charged species. Where the number of electrons and the number of protons differ.
What are cations?
Positive ions, species with fewer electrons than protons.
What are anions?
Negative ions, species with more electrons than protons.
What do atoms of metals on the left of the periodic table tend to do with their electrons?
Lose them to form cations.
What do atoms of non-metals on the right of the periodic table tend to do with their electrons?
Gain them to form anions.
What is a binary compound?
A compound containing only two elements. ends in an ‘ide’ eg hydroxide- oxygen and hydrogen
What are polyatomic ions?
Ions contain atoms of more than one element bonded together
What is the formula and charge of an ammonium ion?
NH(4)
1+
What is the formula and charge of a hydroxide ion?
OH-
1-
What is the formula and charge of a nitrate ion?
NO(3)-
What is the formula and charge of a nitrite ion?
NO(2)-
What is the formula and charge of a hydrogen carbonate ion?
HCO(3)-
What is the formula and charge of a carbonate ion?
CO(3) 2-
What is the formula and charge of a sulfate ion?
SO(4) 2-
ate = means the ion contains oxygen
What is the formula and charge of a sulfite ion?
A sulphite ion is SO(3) 2-
What is the formula and charge of a phosphate ion?
PO(4) 3-
What is the formula and charge of a zinc ion?
Zn 2+
What is the formula and charge of a sodium ion?
Na 1+
What is the formula and charge of a halide ion?
F/Cl/Br/I/At 1-
What is the formula and charge of an aluminium ion?
Al 3+
What must an ionic compound have?
An overall charge of zero.
What is a diatomic molecule?
Two atoms of the same element bonded together.
Do covalent compounds contain ions?
No, they do not.
Where are state symbols shown in chemical equations?
In subscript in brackets after a formula.
What charge do aluminium ions form?
aluminium forms 3+ ions
What charge ions does silver form?
silver(Ag) forms a 1+ ion
what charge ions does zinc form?
zinc forms a 2+ ions
what ions do iron form?
iron forms a 2+/3+ ions
what charge ions does copper form?
copper forms a 1+/2+ ions
what charge ions does lead form?
lead forms 2+/4+ ions
What is an acid?
A proton / hydrogen ion donor
What is a strong acid?
Fully dissociates/ ionises to release all of its hydrogen ions / protons into solution.
It completely dissociates in aqueous solution.
What is a weak acid?
It partially dissociates/ ionises in aqueous solution, releasing some of its protons
What is a base?
A proton / hydrogen ion acceptor.
What are some examples of bases?
there are several types of bases
metal oxides
metal hydroxides
metal carbonates
alkalis
What is an alkali?
A base that dissolves in water releasing hydroxide ions into the solution.
What is the word equation for the neutralisation of acids with metal oxides/hydroxides?
Metal oxide/hydroxide + acid -> salt + water
What is the word equation for the neutralisation of acids with alkalis?
Acid + alkali -> salt + water
ammonia + acid = ?
ammonia ,NH3 reacts with acds by accpeting H+ to form ammonium salts containg an ammonium ion
e,g
HCl + NH3 = NH4Cl
What is the word equation for the neutralisation of acids with carbonates?
Carbonate + acid -> salt + water + carbon dioxide
What is the word equation for the reaction of a metal with acid?
Metal + acid -> salt + hydrogen
Explain what is meant by a salt (1)
When the H+ in an acid is replaced by a metal ion
What calcium compound is formed when calcium oxide reacts with water? (1)
Calcium hydroxide
What calcium compound is formed when calcium oxide reacts with nitric acid? (1)
caO(s)+2HNO3(aq)→Ca(NO3)2(aq)+H2O(l)
forms calcium nitrate
How do old samples of magnesium oxide become contaminated with magnesium carbonate? (1)
MgO has reacted with CO2
A student adds an excess of HCl to magnesium oxide and magnesium carbonate, state two observations that would be made (2)
Solid dissolves
Effervescence
Define an acid (1)
A proton donor
How can CaCO3 be used to combat excess stomach acid? Use an equation (2)
CaCO3 neutralises HCl
CaCO3 + 2HCl -> CaCl2 + H2O + CO2