Precipitation reactions and neutralization reactions (that don't contain carbonate or
bicarbonate) are reactions.
a. single displacement
b. double displacement
c. synthesis
d. decomposition

The answer to your question is: b. Double replacement reactions.

Explanation:

Example

Neutralization reaction:

                 HCl  +  NaOH   ⇒   NaCl + H₂O

Precipitation reaction

                 AgNO₃ + NaCl ⇒   AgCl  + NaNO₃            

answer: semi-infinite solid initially at a uniform temperature of 400 ◦c is cooled at its surface by convection. the cooling fluid at a constant temperature of 200 ◦c has a convective coefficient (ha) of 250 w/m2.k. the physical properties of the solid: k = 20 w/m.k and α = 4 * 10-5  m2/s. using δx = 0.04 m and δt = 10 s. write the finite difference equations describing the transient heat transfer of the first five δx and the temperature profile after 30 s.