Single Replacement Reactions

Understand this first!

• Writing formulas for compounds

-Ex. Al2O3 (Balancing positive and negative charge)

• Balancing equations (7.4)

• HONClBrIF

Understanding Single Replacement

• Single-Replacement Reaction: Atoms of an element replace the atoms of a second element in a compound

• Activity Series of Metals: A list of metals on order of decreasing reactivity

• (S) (L) (G) (aq) Solid, Liquid, Gas, Dissolved in water

A + BC B + ACThink of it like this!

How to understand the table

•In both the tables shown the highest element is able to knock out any other elements below it.

•The ones below it are unable to knock out the ones above it.

•F can knock out Cl, Br, I, and At but they can’t knock out F. Li can knock out K, Ca, Na, Mg, Al, Zn, Fe, Pb, H, Cu, Hg, Ag but they can’t knock out K.

Using the table

1) Check if element will replace the other element in the compound

2) If the isolated element is greater than the element in the compound, then it will replace the lower element in the equation

3) If you get an unbalanced equation that’s where chapter 7.4 comes in, in order to balance out the equation

Practice Problems

Zn(s) + H2S04 (aq) ZnSO4(aq) + H2(g)

Practice Problems

Zn(s) + H2S04 (aq) ZnSO4(aq) + H2(g)

•Zn has a +2 charge and so does H2

•Zn replaces H without balancing needed

Practice problems

Al(NO3)3+Mg Mg(NO3)2 + Al Unbalanced

•In Al(NO3)3 = three of NO3

•In (NO3)2 = two of NO3

•To get them the same of NO3 you need to put them to a common quantity (which is six)

2Al(NO3)3+3Mg 3Mg(NO3)2 + 2Al Balanced

Mg(NO3)2 + Al Unbalanced

Practice Problems

Cl2 + 2NaI I2 + 2NaCl

Practice Problems

Cl2 + 2NaI I2 + 2NaCl• Cl is greater than I so its replaces it• Beware of HONClBrIF when that element is alone it

has 2

Practice Problems

Cl2 + 2NaI I2 + 2NaCl• Cl is greater than I so its replaces it• Beware of HONClBrIF when that element is alone it

has 2• To balance you put 2 NaI and 2 NaCl because there is

2 Cl in the first equation and 2 I in the second. And you have to balance the NaI and NaCl so that both sides have Cl2 and I2

Practice Problems

Ag(s) + KNO3(ag) No Reaction (NR)

• Ag is lower on the chart than K so it can’t replace it

No Reaction (NR)

Homework

Solve by single replacement to the balanced form

1. Al + CuCl2

2. Br2 + CaI2

3. Cu + FeSO4