Question

use oxidation numbers to decide which of the following are redox reactions. for all redox reactions identify the oxidizing agent and the reducing agent. a) SiO2(S)+4HF(g)--->SiF4(g)+2H2O(l) b)2C2H6(g)+7O2--->4CO2(g)+6H2O(g) c) 5CO(G)+l2O5(s)--->5CO2(g)+l2(s)

Answer 1

Reduction = species that GAINS electrons

Oxidation = process in which a specie will LOSS electrons

Reducing agent = The species that favors reduction, i.e. it will oxidize in order to reduce another species

Oxidizing agent = The species that favors oxidation, i.e. it will reduce in order to oxidise another species

a) SiO2(S)+4HF(g)--->SiF4(g)+2H2O(l)

Si goes from +4 in SiO2 to +4 in SiF4, no change

H goes form +1 in HF to H2O

no redox

b)2C2H6(g)+7O2--->4CO2(g)+6H2O(g)

C goes from --> -3 in C2H6 to -2 in CO2, it is lsoingelectrons

O2 goes from 0 to -2 in H2O, it is gaining electrons

this must be REDOX reaction

since C2H6 is being oxidized, it must be the REDUCING AGENT

sinc eO2 is being reduced, it must be the OXIDIZING AGENT

c) 5CO(G)+l2O5(s)--->5CO2(g)+l2(s)

C goes from -2 to -4

I goes from +5 to 0

this is also redox, reaction

CO is getting oxidized, so it is the REDUCING AGENT

I2O5 is getting reduced, so it is the OXIDIZING AGENT