A mixture of NaCl and NaBr has a mass of 2.04g and is found to contain 0.70g of Na. What is the mass of NaBr in the mixture?
Well, it seems like we have a salty situation here! Let's break it down.
We know that the mass of the mixture is 2.04g, and it contains 0.70g of Na.
Since sodium (Na) is present in both NaCl and NaBr, we can assume that the mass of Na in the mixture is contributed by both compounds. So, we need to figure out the mass of Na in NaBr and subtract it from the total mass of Na.
To do that, we first need to find the molar mass of NaCl and NaBr. The molar mass of NaCl is 58.44g/mol, and the molar mass of NaBr is 102.89g/mol.
Now, let's find the molar ratio of NaCl and NaBr. For NaCl, the molar ratio of Na is 1, and for NaBr, the molar ratio of Na is also 1.
Since we have 0.70g of Na, we can set up the following equation to find the mass of NaBr:
(0.70g Na) / (Mass of NaBr) = (1 mol Na) / (1 mol NaBr) x (molar mass of NaBr)
Simplifying this equation, we get:
0.70g / Mass of NaBr = 102.89g /mol
To find the mass of NaBr, we rearrange the equation:
Mass of NaBr = (0.70g x molar mass of NaBr) / 102.89g
Plugging in the molar mass of NaBr, we get:
Mass of NaBr = (0.70g x 102.89g/mol) / 102.89g
After simplifying, the mass of NaBr in the mixture is... drumroll please...
0.70g!
So, the mass of NaBr in the mixture is 0.70g. Keep that salt shaker handy, and don't let this salty riddle get you in a pickle!
To find the mass of NaBr in the mixture, we need to use the given information about the mass of the mixture and the mass of Na in the mixture.
Let's first calculate the mass of NaCl in the mixture:
- Since we have the mass of Na in the mixture, which is 0.70g, we know that this mass comes from NaCl.
- The molar mass of Na is 22.99 g/mol, and the molar mass of Cl is 35.45 g/mol. So the molar mass of NaCl is 22.99 + 35.45 = 58.44 g/mol.
- To calculate the moles of NaCl in the mixture, divide the mass of Na in the mixture by the molar mass of NaCl: 0.70g / 58.44 g/mol.
- This will give us the moles of NaCl.
Next, let's calculate the mass of NaBr in the mixture:
- We know that the total mass of the mixture is 2.04g.
- Subtracting the mass of NaCl from the total mass will give us the mass of NaBr: 2.04g - mass of NaCl.
Now, let's calculate the mass of NaBr in the mixture:
- Substitute the calculated moles of NaCl back into the molar mass equation to find the mass of NaCl in the mixture.
- Subtract this mass from the total mass of the mixture.
Following these steps will give you the mass of NaBr in the mixture.
A problem with two unknowns and two equations. Solve simultaneously.
Let x = mass NaCl
and y = mass NaBr
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x + y = 2.04
x(atomic mass Na/molar mass NaCl) + y(atomic mass Na/molar mass NaBr) = 0.70
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Substitute the numbers to get this.
x + y = 2.04
x*(23/58.4) + y*(23/102.9) = 0.70
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Solve these two equations. You want y for mass NaBr. Post your work if you get stuck.