Half reaction: Cr₂O₇²⁻(aq) + 7H₂O(l) + 6e⁻ → 2Cr³⁺(aq) + 14OH⁻(aq).
Chromium change oxidation number from +6 in dichromate ion Cr₂O₇²⁻ to +3 in chromium cation.
Sum of the charges on the left side of the half reaction is -2 and on the left side is -8 (2·(+3) +14·(-1)), so six electrons must be added on the left side of half reaction.
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p2, valence shell: 4s2 3d10 4p2
Answer:
B) an anion
Explanation:
During bonding atoms may share electron or give out electron . In the case of electrovalent or ionic bonding, electron(s) is/are transferred from one atom to another . The atom that donate the electron are known as donor atom and the atom that receives the electron are known as receivers.
The atom that donate the electron becomes a cation(positively charged) as it lose it electron(s) while the receiver gains electron to become an anion which is a negatively charge ion.
An example of such interaction is between a sodium atom and a chlorine atom. The Na atom lose it electron to become positively charged(cation) while the chlorine atom gains electron to become negatively charged(anion). Both atom bond together losing and gaining electron to fulfill the octet rule.
Na+ + Cl- → NaCl
Answer:
17
Explanation:
the atomic mass is away protons + neutrons, electrons are neglatable.
Answer:
I would say that it is the bond called complementary hydrogen bonds
Explanation:
The nucleotides in a base pair are complementary which means their shape allows them to bond together with hydrogen bonds. The A-T pair forms two hydrogen bonds. The C-G pair forms three. The hydrogen bonding between complementary bases holds the two strands of DNA together.
