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When Ions Combine. If you give me your spare electron then you’ll see how attractive I am. Phwar… You’re right. I am very strongly attracted to you, baby. When a non-metal atom takes an electron from a metal atom two ions will form. They will be oppositely charged and attract each other.
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If you give me your spare electron then you’ll see how attractive I am.
Phwar… You’re right. I am very strongly attracted to you, baby.
When a non-metal atom takes an electron from a metal atom two ions will form. They will be oppositely charged and attract each other.
Whenever a positive ion forms there must also be a negative ion formed as well. In other words a metal atom will only lose its electrons if a non-metal atom is taking them. Electrons don’t just exist by themselves, they must be associated with an atom.
The law of charges says that differently charged objects will attract.
Which of the following pairs will attract each other (ie which of the following pairs have different charges?) (a) a proton & an electron (b) two protons (c) two electrons (d) two sodium ions (e) an electron & a chloride ion (f) a magnesium ion and an oxygen atom (g) a magnesium ion and an oxygen ion (h) an aluminium ion and a sulfate ion.
Which of the following pairs will attract each other (ie which of the following pairs have different charges?) (a) a proton & an electron (b) two protons (c) two electrons (d) two sodium ions (e) an electron & a chloride ion (f) a magnesium ion and an oxygen atom (g) a magnesium ion and an oxygen ion (h) an aluminium ion and a sulfate ion.
When oppositely charged ions attract each other the total charge will always equal zero. eg each Ca+2 ion will attract one O-2 ion. ie (+2) + (-2) = 0 and each Ca+2 ion will attract two Cl-1 ions ie (+2) + (2x(-1)) = 0 When oppositely charged ions attract, then they are held together to form ionic compounds. We can represent these compounds with ionic formulae. The compounds in the example above are: CaO and Ca Cl2.
How to write ionic formulae. 1. The first name is the (+) ion and the second name is the (-) ion. eg: sodium bromide 2. Look up and write the symbols for the ions. Na+1 Br-1 3. The sum of the positive and negative oxidation numbers must be zero. ie: +1-1=0 4. If it is then write the two symbols together without the charges. ie: NaBr 5. If it is not, add more positive or more negative ions until it is. 6. Use a subscript number to indicate more than one ion. eg: Na2S, CaCl2.
What happens when radical ions are involved in an ionic compound? The rules are the same for writing formula for compounds containing radical ions as for those containing monatomic ions. The only difference is when you need more than one radical to balance the charge of the other ion.
What happens when radical ions are involved in an ionic compound? For example if calcium ions combined with nitrate ions: The calcium ion (Ca+2) would need two nitrate radical ions (NO3-1) to balance its charge.
How do we represent this compound? If we wrote CaNO32 we would be wrong. That formula says that for every calcium ion there are one nitrogen and 32 oxygen atoms!!! There are no nitrate ions (ie NO3-1) in the formula CaNO32.
How do we represent this compound? We want the formula to represent one calcium ion for every two nitrate ions. So we write: Ca(NO3)2 The two outside the brackets means that there is two of everything inside it.
