How does #"silver bromide"# react with #"sodium thiosulfate"#? What mass of sodium thiosulfate is required to react with a #0.22*g# mass of #"silver bromide"# to give the complex ion #Na_3[Ag(S_2O_3)_2]#?

Question

How does #"silver bromide"# react with #"sodium thiosulfate"#?  What mass of sodium thiosulfate is required to react with a #0.22*g# mass of #"silver bromide"# to give the complex ion #Na_3[Ag(S_2O_3)_2]#?

Peyton Adams · Accepted Answer

We assess the reaction:

#AgBr(s)uarr + 2Na_2S_2O_3(aq) rarr Na_3[Ag(S_2O_3)_2](aq) + NaBr(aq)# Photographs in black and white still employ this complexation reaction. And clearly, given the stoichiometric reaction, there is #1:2# stoichiometric equivalence between moles of #"silver bromide"#, and moles of #"sodium thiosulfate"#, and #1:1# stoichiometric equivalence between moles of #"silver bromide"#, and moles of #"silver(I) thiosulfate anion"#. #"Moles of silver bromide"=(0.22*g)/(187.77*g*mol^-1)=1.17xx10^-3*mol#. Clearly there is a #1.17xx10^-3*mol# quantity of #Na_3[Ag(S_2O_3)_2]#. And this represents a mass of .......................... #1.17xx10^-3*molxx401.11*g*mol^-1~=0.50*g#

Natalie Anton · Answer

undefined Silver bromide reacts with sodium thiosulfate to form a complex ion Na3[Ag(S2O3)2]. The balanced chemical equation for this reaction is:

2AgBr + 3Na2S2O3 → Na3[Ag(S2O3)2] + NaBr

To calculate the mass of sodium thiosulfate required to react with 0.22 g of silver bromide, you first need to determine the molar mass of silver bromide (AgBr) and sodium thiosulfate (Na2S2O3).

The molar mass of AgBr:
Ag: 107.87 g/mol
Br: 79.90 g/mol
AgBr: 107.87 + 79.90 = 187.77 g/mol

The molar mass of Na2S2O3:
Na: 22.99 g/mol
S: 32.07 g/mol
O: 16.00 g/mol
Na2S2O3: 2(22.99) + 2(32.07) + 3(16.00) = 158.11 g/mol

Now, use the stoichiometry of the balanced equation to find the mass of sodium thiosulfate required.

From the balanced equation, 2 moles of AgBr react with 3 moles of Na2S2O3.

Moles of AgBr = mass of AgBr / molar mass of AgBr
Moles of AgBr = 0.22 g / 187.77 g/mol ≈ 0.00117 mol

Using the mole ratio from the balanced equation:
Moles of Na2S2O3 = (3/2) * Moles of AgBr
Moles of Na2S2O3 = (3/2) * 0.00117 mol ≈ 0.00175 mol

Now, calculate the mass of Na2S2O3 required:
Mass of Na2S2O3 = Moles of Na2S2O3 * molar mass of Na2S2O3
Mass of Na2S2O3 = 0.00175 mol * 158.11 g/mol ≈ 0.277 g

So, approximately 0.277 g of sodium thiosulfate is required to react with 0.22 g of silver bromide to form the complex ion Na3[Ag(S2O3)2].