Download presentation
Presentation is loading. Please wait.
1
Naming and Writing Covalent Compounds
2
Practice Writing Covalent Compounds
Manganese (III) chlorate ID the ions Us the X-over technique Write the formula Use brackets correctly to show the ratio Mn3+ and ClO3 Mn1 and (ClO3)3 Mn(ClO3)3
3
Ammonium sulfate NH4+ and SO42-
Another Example Ammonium sulfate NH4+ and SO42- (NH4)2 and SO4 (NH4)2SO4
4
Writing Names of compounds with polyatomic ions
Fe(OH)3 Iron can be 3+ or 2+ hydroxide ion is 1- Ion Forms Fe(OH)3 Use the X-over technique The ion form for Iron is 3+ Iron (III) hydroxide Compound Name is:
5
Work with a partner to answer these questions
See text, page 193 Number 1, b) c) g) j) Number 2, b) f) g) i) We will mark these together and you will hand yours in
6
Naming Covalent Compounds
Ions are not formed, instead atoms combine chemically by sharing electrons Covalent compounds, also called molecules, rely on the chemical formula to reveal the components of the molecule.
7
Subscripts mean something different in covalent compounds
Subscripts in ionic compounds show the smallest whole-number ratio between the ions in the compound. (Remember you must write the formula in its most reduced form.) Covalent molecules have subscripts that show the actual number of atoms in the molecule. H2O, commonly known as water H2O2, commonly known as hydrogen peroxide (this is not reduced)
8
Naming Binary Covalent Compounds
Contains two non-metal elements joined by one or more covalent bonds Covalent compounds may have many or few atoms sharing electrons. CH4 = methane and C25H52 = candle wax Prefixes are often used before the atom name to indicate the number of atoms in the molecule. CO = carbon monoxide, CO2 = carbon dioxide Write the most metallic atom (farthest left) first Add -ide to the end of the second atom’s name
9
Trisilicon hexaphosphide
What is the chemical formula for the molecule trinitrogen tetrachloride? N3Cl4 What is the name of the molecule Si3P6? Trisilicon hexaphosphide Page 194: Table 4.13
10
Activity: Get to know the Molecular Model Sets
Form these covalent compounds and draw what they look like as a molecule Arsenic tetrachloride Methane (page 195) NI3 Water (how many lone pairs of electrons does the O have in this molecule?) Ammonia (page 195) Carbon dioxide (carbon forms a double bond with oxygen- use 2 toothpicks beside each other as a double bond)
11
Homework Text, page 195 Number 1, all Number 2, all
If you have finished come and show me and you can check your answers with the answer key
12
To determine whether a compound is ionic or covalent:
Examine the formula. Ionic compounds start with a metal or the ammonium ion. Covalent compounds start with a non-metal. If the compound is covalent: Use the prefix system of naming if the compound is binary and does not start with hydrogen. If there are more than two different elements, or it starts with H, there is probably a different, simpler name for the covalent molecule. If the compound is ionic: Check the metal to see if it is multivalent (add a Roman numeral if it is multivalent). Naming starts with the name of the metal atom. If it ends with a single non-metal, naming will just end in -ide. If it ends in a polyatomic ion, look up the name/formula. See pages
Similar presentations
© 2025 SlidePlayer.com Inc.
All rights reserved.