Question

For questions 18-21, . In each space, classify the reaction type.

Answer 1

Answer:

$2LiBr+Pb(NO_3) = PbBr_2+ 2LiNO_3$  is a double displacement reaction

• $Fe+2HCl = FeCl_2+2H_2$ is a redox reaction

• $CaO+H_2 O = Ca(OH)_ 2$is a combination reaction

• $NiCl_2 = Ni+Cl_2$  is a decomposition reaction

Explanation:

$2LiBr+PbNO_3 = PbBr_2+2LiNO_3$

                                                       It is of the form $AX+BY = AY+BX$

                                                       $Fe+2HCl = FeCl_2+H_2$

Both oxidation and reduction occur in this reaction. Fe gets oxidized and H gets reduced.

                                          $Fe = Fe^(2+)+2e^-$

                                          $2H^++2e^- = H_2$

                                          $CaO+H_2 O = Ca(OH)_2$

It is an exothermic combination reaction. Calcium reacts with water to produce calcium hydroxide and heat is released in this process.

• $NiCl_2 = Ni+Cl_2$

It is a decomposition reaction where nickel chloride decomposes to nickel and chlorine.

Answer 2

Answer:

18. Double Displacement Reaction

19. Single Displacement Reaction

20. Synthesis Reaction

21. Decomposition Reaction

Explanation:

Double Displacement formula:

AB + CD --> AD + CB

Single Displacement formula:

A + BC --> AC + B

Synthesis formula:

A + B --> AB

Decomposition formula:

AB --> A + B