sodium sulfide and cadmium nitrate undergo a double displacement reactions as shown by the following equation Na2S cd(NO3)2 -> 2NaNO3 CdS What is the mass, in milligrams,of cadmium sulfide that can be made from 5.00mg of sodium sulfide?
Here is an example. Just follow the steps.
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To find the mass of cadmium sulfide that can be made from 5.00 mg of sodium sulfide, we need to use stoichiometry and the molar masses of the compounds involved.
First, let's calculate the molar mass of sodium sulfide (Na2S) and cadmium sulfide (CdS):
Molar mass of Na2S:
2(Na) = 2(22.99 g/mol) = 45.98 g/mol
1(S) = 1(32.07 g/mol) = 32.07 g/mol
Total molar mass = 45.98 + 32.07 = 78.05 g/mol
Molar mass of CdS:
1(Cd) = 1(112.41 g/mol) = 112.41 g/mol
1(S) = 1(32.07 g/mol) = 32.07 g/mol
Total molar mass = 112.41 + 32.07 = 144.48 g/mol
Next, we need to find the molar ratio between sodium sulfide and cadmium sulfide from the balanced equation:
Na2S + Cd(NO3)2 -> 2NaNO3 + CdS
From the equation, we can see that for every 1 mole of sodium sulfide, we get 1 mole of cadmium sulfide.
Now let's calculate the number of moles of sodium sulfide:
Mass of Na2S = 5.00 mg = 5.00 × 10^-3 g
Number of moles = mass / molar mass = 5.00 × 10^-3 g / 78.05 g/mol ≈ 6.408 × 10^-5 mol
Since the molar ratio between sodium sulfide and cadmium sulfide is 1:1, we have 6.408 × 10^-5 mol of cadmium sulfide.
Finally, let's calculate the mass of cadmium sulfide:
Mass of CdS = number of moles × molar mass = 6.408 × 10^-5 mol × 144.48 g/mol ≈ 9.25 × 10^-3 mg
Therefore, the mass of cadmium sulfide that can be made from 5.00 mg of sodium sulfide is approximately 9.25 × 10^-3 mg.