3A2 Systematic Naming and Formulas Flashcards
Identify chemical formulas and name simple inorganic compounds, acids, bases, salts, and hydrates.
What is the naming convention for covalent compounds?
- Use prefixes for quantity.
- Change the ending of the second element to ‘ide’.
Example: Carbon dioxide (CO₂).
What is a hydrate?
A compound that contains water molecules within its crystal structure.
Hydrates often lose water when heated.
Hydrated compounds are often crystalline.
List two examples of hydrates.
- Gypsum (CaSO₄·2H₂O)
- Epsom salt (MgSO₄·7H₂O)
These compounds contain water in their crystalline structure.
Epsom salts are used in baths to relieve sore muscles.
State one property of hydrates.
They often dissolve in water to release their water of hydration.
This is a distinguishing characteristic of hydrates.
How is the formula of a hydrate determined experimentally?
By measuring mass before and after heating to find the water content.
This helps determine the mass of water removed.
Mass of water = Mass of hydrate - Mass of anhydrate.
True or False:
Anhydrous compounds are always less stable than hydrates.
False
Stability depends on the specific compound and environmental conditions.
Define:
anhydrate
A hydrate with the water removed.
Anhydrates are used as drying agents.
Anhydrates are formed when hydrates are heated.
How can a hydrate be converted to an anhydrous compound?
By heating the hydrate to remove water molecules.
This process is called dehydration.
An anhydrous compound does not contain water in its structure.
What is the naming convention for hydrates?
- Name the compound.
- Add a prefix indicating the number of water molecules.
- Add the word ‘hydrate’.
Example: CuSO₄·5H₂O is copper (II) sulfate pentahydrate.
Which prefix is used for a hydrate with seven water molecules?
hepta-
Example: MgSO₄·7H₂O is magnesium sulfate heptahydrate.
What is a binary ionic compound?
A compound consisting of two elements: one cation and one anion.
List five differences between covalent and ionic compounds.
- Electrons: Shared in covalent but donated in ionic.
- Melting and Boiling Point: Low in covalent but high in ionic.
- Conduction: Poor in covalent but good in ionic.
- Solubility: Poor in covalent but high in ionic.
- Brittleness: Covalent are flexible while ionic are brittle.
These differences lead to distinct physical properties.
How are binary ionic compounds named?
With the cation first, then the anion.
Anions often end in “-ide,” “-ate,” or “-ite.”
Example: sodium chloride (NaCl).
Define:
polyatomic ion
A charged particle composed of two or more atoms covalently bonded.
Examples include sulfate (SO₄²⁻) and ammonium (NH₄⁺).
How do you name a transition metal in an ionic compound?
By using Roman numerals to indicate its oxidation state.
Example: FeCl₂ is iron (II) chloride.
List two examples of ionic compounds with transition metals.
- Copper (II) sulfate (CuSO₄)
- Iron (III) oxide (Fe₂O₃)
Transition metals often have multiple oxidation states.
True or False:
All ionic compounds are binary.
False
Some ionic compounds, like calcium carbonate (CaCO₃), contain polyatomic ions.
What is the charge of a sulfate ion?
-2
Sulfate’s chemical formula is SO₄²⁻.
Define:
oxidation state
The charge of an atom in a compound if all bonds were ionic.
Also known as oxidation number.
How do you write the formula for magnesium nitrate?
Mg(NO₃)₂
Magnesium has a +2 charge, nitrate has a -1 charge.
Fill in the blank:
_____ chloride is the name for FeCl₃.
Iron(III)
The Roman numeral indicates the iron’s +3 oxidation state.
How are acids named based on anion endings?
- -ide becomes hydro -ic acid
- -ate becomes -ic acid
- -ite becomes -ous acid
Example:
- HCl is hydrochloric acid
- H₂SO₄ is sulphuric acid
- HNO₂ is nitrous acid
What is the naming convention for hydroxide bases?
The metal cation is followed by hydroxide.
Example: KOH is potassium hydroxide.
What is an example of a strong acid?
Hydrochloric acid
(HCl)
Strong acids completely ionize in water.
What is an example of a strong base?
Sodium hydroxide
(NaOH)
Strong bases dissociate completely in water.
