CR2 battery health status

1. In this reaction, the valence of Cr element changed from +6 to +3, the valence of C element changed from -2 to 0, the amount of ethanol =46g46g/mol= 1mol, and the number of electrons transferred by 1mol ethanol completely = 1mol× 2xna/mol =

Two. (1) Iron loses electrons on the anode to generate Fe 2+, which is reducible, reducing Cr2O72- to Cr3+, so the answer is:

Fe2+；

(2) When consuming 28gFe, n(Fe)=28g56g/mol=0.5mol, and the number of transferred electrons =0.5mol×2×NA/mol=NA, so the answer is: Na;

(3) The lime milk reacts with chromium ions to generate chromium hydroxide precipitate and calcium ions. Ionic equation is 2cr3++3ca (OH) 2 = 2cr3+3ca2+, so the answer is 2cr3++3ca (OH) 2 = 2cr3+3ca2+.