Question

which reaction involves elements from group 2 and group 16?

h2 + cl2 → 2 hcl

na + cl2 → 2 nacl

4 fe + 3 o2 → 2 fe2o3

2 ca + o2 → 2 cao

Explanation:

Step1: Identify elements in each reaction

• For \(H_2 + Cl_2

ightarrow2HCl\): \(H\) is in Group 1, \(Cl\) is in Group 17.

• For \(2Na + Cl_2

ightarrow2NaCl\): \(Na\) is in Group 1, \(Cl\) is in Group 17.

• For \(4Fe + 3O_2

ightarrow2Fe_2O_3\): \(Fe\) is a transition metal (not Group 2), \(O\) is in Group 16.

• For \(2Ca+O_2

ightarrow2CaO\): \(Ca\) is in Group 2, \(O\) is in Group 16.

Answer:

\(2Ca + O_2
ightarrow2CaO\)