The chemical equation for a reaction between k2cr2o7 and hcl is shown. k2cr2o7 + 14hcl → 2crcl3 + 2kcl + 3cl2 + 7h2owhich of the following identifies the reactant that acts as an oxidizing agent in the reaction and explains the answer? k2cr2o7, because the oxidation number of k changes from +6 to +3. k2cr2o7, because the oxidation number of cr changes from +6 to +3. hcl, because the oxidation number of h changes from −1 to 0. hcl, because the oxidation number of cl changes from −1 to 0.

K2Cr2O7 + 14HCl → 2CrCl3 + 2KCl + 3Cl2 + 7H2O

the correct option is :

K2Cr2O7, because the oxidation number of Cr changes from +6 to +3.

Oxidation number of Cr in K2Cr2O7 is:

K2Cr2O7 = 2K + 2 Cr + 7 O

= 2(+1) + 2Cr + 7(-2)

= 2 + 2Cr -14

[total charge on K2Cr2O7 = 0], Hence;

2 + 2Cr -14 = 0

2Cr -12 = 0

2Cr = 12

Cr = 12/2

Cr = +6

Oxidation number of Cr in CrCl3 is:

CrCl3 = Cr + 3Cl = 0

Cr + 3(-1) = 0

Cr -3 = 0

Cr = +3

Hence Cr is changing its oxidation number from

+6 in K2Cr2O7 to +3 in CrCl3.

Since the oxidation number of Cr [ +6 → +3] is decreasing here,

Cr is getting reduced.

so K2Cr2O7 is an oxidizing agent,as it is getting itself reduced and oxidizes others.

K2Cr2O7, because the oxidation number of Cr changes from +6 to +3.

Explanation:

took the test

explanation:

metals have excess of electrons whereas non-metals have deficiency of electrons. thus, in order to gain stability metals easily donate their electrons to the non-metals.

for example, electronic configuration of sodium is and electronic configuration of phosphorous is .

when a phosphorous atom and sodium atom combine together then sodium will donate is extra one electron to the phosphorous atom. as a result there will be formation of ionic bond between sodium and phosphorous.

the reaction will be as follows.

there, are three sodium sodium atoms and each of them will donate its one extra electron to phosphorous atom. thus, the sub-shell of phosphorous gets completely filled.  

thus, we can conclude that electrons are transferred from atoms of sodium to atoms of phosphorous. this transfer makes the sodium atoms donate one electron and the phosphorous atoms to gain one electron. as a result, the sodium and phosphorus atoms strongly attract each other.