Question

how do you calculate this:

Calculate the mass of copper needed to displace 5.0g of silver from silver nitrate solution. (Relative Atomic Masses: Ag=108, Cu=63.5)
Eqn=Cu+2AgNO3->Cu(NO3)2+2Ag

How do you write a half equation?
Complete the half equation to show the oxidising action of bromine=
_I- ->I2___
Br2(aq)+2I-(aq)->2Br-(aq)+I2(aq)

Answer 1

I answered this question recently. Perhaps it was for another student. First, please clarify if this is 5.0 g Ag or 5.0 g AgNO3.
If it is 5.0 g Ag, convert 5.0 g Ag to mols, convert mols Ag to mols Cu using the coefficients in the balanced equation, then convert mols Cu to g Cu.
Remember mols = g/atomic mass for conversion of Ag to mols; then conversion of Cu to grams = mols Cu x atomic mass Cu.
The half equation is 2I^- ==> I2 + 2e

Post your work if you get stuck.

Answer 2

Mol=g/atomic mass of Ag wich is 5/108=0.046,usin the coefficients 1molCu produces 2molAg then 0.023mol produces 0.046mol,Cu mol multiplied by Cu atomic mass =1.472

Answer 3

Mol=g/atomic mass of Ag wich is 5/108=0.046,usin the coefficients 1molCu produces 2molAg then 0.023mol produces 0.046mol,Cu mol multiplied by Cu atomic mass =1.472