in the original mixtures, test tube 1 contained a magnesium strip and zinc nitrate, and test tube 2 contained a zinc strip and magnesium nitrate. test tube 3 contained a copper strip and magnesium nitrate, and test tube 4 contained a magnesium strip and copper nitrate. test tube 5 contained a zinc strip and copper nitrate, and test tube 6 contained a copper strip and zinc nitrate. compare what took place in each corresponding pair of test tubes. what general conclusion can you draw?

the picture shows results in each test tube after 24 hours.

In a single replacement reaction, one element in a compound is replaced by another, more active, element. Equations

for single replacement reactions have two general forms. Either a positively charged metal ion is replaced by a more

active metal, or a nonmetal with a negative charge is replaced by a more reactive nonmetal. Nonmetal replacements

involve the halogens. The result is a new element and a new compound.

A + BX à B + AX

Zn(s) + CuSO4(aq) à Cu(s) + ZnSO4(aq), zinc metal replaces the copper II cation

and the blue color of the aqueous copper solution fades

X + AY à Y + AX

Cl2(g) + 2KI(aq) à 2KCl(aq) + I2(s), chlorine replaces the less reactive iodide anions

A colorless KI solution begins to take on a yellow/brown coloration as molecular I2 forms.

Usually, the newly made compound stays dissolved in solution, but sometimes it may form a solid. The lone elements

are usually metal atoms or diatomic molecules such as hydrogen or the halogens.