Question

Which of the following chemical reactions is an oxidation-reduction reaction?

CuSO4 + BaCl2 yields BaSO4 + CuCl2
Pb(NO3)2 + 2NaCl yields PbCl2 + 2NaNO3
N2 + 3H2 yields 2NH3
K2SO4 + BaCl2 yields BaSO4 + 2KCl

Answer 1

Put on the ox number by the following rules: http://www.dummies.com/how-to/content/rules-for-assigning-oxidation-numbers-to-elements.html

Element which get change in ox.n. are or ox or red. Whan you had a raction containing ox and red atoms, its a red-ox

Answer 2

@taramgrant0543664 would c be correct?

Answer 3

Yes c would be correct

Answer 4

What is true of an element that was oxidized in a chemical reaction?

It lost electrons.
It gained electrons.
It increased electronegativity.
It decreased electronegativity.

Answer 5

would b be correct @taramgrant0543664 ?

Answer 6

Lose electrons oxidized, gain electrons reduced

Answer 7

so a would be correct @taramgrant0543664

Answer 8

Yes a would be correct

Answer 9

What is the oxidation number of oxygen (O) in O2?

0
+2
−2
+4

Answer 10

would b be correct @taramgrant0543664

Answer 11

Rule 1: The oxidation number of an element in its free (uncombined) state is zero — for example, Al(s) or Zn(s). This is also true for elements found in nature as diatomic (two-atom) elements

Answer 12

so @Bozhena b would be wrong

Answer 13

yes, b is wrong

Answer 14

It's electrically neutral just like we did with F2

Answer 15

so a would be right?

Answer 16

It would be a since it would become neutral

Answer 17

Which of the following describes an element that is reduced in a reaction?

It acts in the reactant that is the reducing agent.
It has a decrease in its oxidation number.
Cd yields Cd2+ + 2e−
Zn + Cu2+ yields Zn2+ + Cu

Answer 18

for c and d are both incorrect ithink

Answer 19

Gaining electrons is reduced and therefore the oxidation number would become more negative so there would be a decrease in oxidation number

Answer 20

so b is correct

Answer 21

Yes it would be