2CrO₄²⁻(aq) + 2H⁺(aq) ⇄ Cr₂O₇²⁻(aq) + H₂O(l)

1. a)c-14 has two more protons

2. d)they have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.

3. c) iron and nickel.

level 4 to level 2 : ))

i believe the answer is 5,000