Redox Reactions: Identifying and Understanding Chemical Transformations

[nothing123]

Which of the following is a redox reaction?
A. TiCl4(g) + 2 Mg(l) D Ti(s) + 2 MgCl2(l)
B. NH3(g) + CO2(g) + H2O(l) NH4HCO3(aq)
C. NaCl(s) + NaHSO4(s) D HCl(g) + Na2SO4(s)
D. NaOH(aq) + H3PO4(aq) NaH2PO4(aq) + H2O(l)
E. None of the above

Is it A?

Also another q.
The primary reason for the nonexistence of NaCl2 is that:
A. Cl has a low electron affinity.
B. the Cl2
– ion has been observed only as a ligand in coordination complexes of transition metal ions.
C. NaCl2 would have very high lattice energy.
D. the expected repulsion between the Cl atoms is strong.
E. Na has a high second ionization energy.

I'm leaning towards E...

 

[Borek]

I would accept both answers, but that's me.