If I did this correctly the balanced equation would be:
14H⁺+Cr₂O₇²⁻+6I⁻→3I₂+2Cr³⁺+7H₂O
oxidation half: (iodide was oxidized)
2I⁻→I₂+2e⁻
reduction half: (chromium was reduced)
14H⁺+Cr₂O₇²⁻+6e⁻→2Cr³⁺+7H₂O
H⁺ comes from the solution. It is in the final reaction since in redox reactions the oxygen is turned into water since it can't just go away. I multiplied the oxidation half reaction by 3 in order for both half reactions to half the same number of electrons since equal numbers of electrons need to be lost and gained for the reaction to be balanced.
I hope this helps. Let me know if anything is unclear.
To find out how many grams are in 4.65 moles of Al(NO₂)₃
Find out what the molar mass of Al(NO₂)₃ is
Al = 26.98 g/mol Al
N = 14 g/mol N
O = 16 g/mol O
Next, you have to look at the subscripts and figure out which they belong to, in this case:
Al = 26.98 g/mol Al
N₃ = 42 g/mol N₃
O₆ = 96 g/mol O₆
Finally, add the numbers together, so:
26.98 g/mol Al + 42 g/mol N₃ + 96 g/mol O₆ =
164.98 g/mol Al(NO₂)₃
Now, you have 4.65 mol Al(NO₂)₃ so
164.98 g/mol Al(NO₂)₃ × 4.65 mol Al(NO₂)₃ =
767.157 grams of Al(NO₂)₃
"Atoms have an equal proton and neutron charge."
Answer:
5.0 38 84.0 749.7 528.0 729.0 738.9 739.0
