Could someone walk me through the steps to solve this problem...
The molar mass of the metal hydroxide M(OH)2 is 74.10 g/mol. What is the molar mass of the sulfide of this metal?
Textbook Problem E.15 [ENDORSED]
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Re: Textbook Problem E.15 [ENDORSED]
Since you know (OH)2 is part of the metal hydroxide you can find that molar mass which is 34.02 grams/mol. You are given that teh entire metal hydroxide molar mass is 74.10 grams/mol.
74.10 grams/mol - 34.02 grams/mol = 40.08 grams/mol
This molar mass is the molar mass of Ca.
Therefore, the metal hydroxide would be Ca(OH)2
The problem asks you to find the molar mass of the sulfide of this metal: CaS
40.08 grams/mol + 32.06 grams/mol = 72.14 grams/mol of CaS
74.10 grams/mol - 34.02 grams/mol = 40.08 grams/mol
This molar mass is the molar mass of Ca.
Therefore, the metal hydroxide would be Ca(OH)2
The problem asks you to find the molar mass of the sulfide of this metal: CaS
40.08 grams/mol + 32.06 grams/mol = 72.14 grams/mol of CaS
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Re: Textbook Problem E.15
To put it simply, this problem is asking you to basically find a type of metal, add sulfur to that metal, and then find the molar mass of that metal and the sulfur.
1.) subtract the molar masses of hydrogen and oxygen from the total molar mass given.
2.) find an element on the periodic table that has the same/ closest molar mass to what you found from subtraction in Step 1.
3.) Add a sulfate to this.
4.) Calculate the molar mass of element found and the sulfate. (Add together since they are a compound)
1.) subtract the molar masses of hydrogen and oxygen from the total molar mass given.
2.) find an element on the periodic table that has the same/ closest molar mass to what you found from subtraction in Step 1.
3.) Add a sulfate to this.
4.) Calculate the molar mass of element found and the sulfate. (Add together since they are a compound)
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Re: Textbook Problem E.15
Well the first step is to identify what the sulfide would look like. Because Ca would give up its two valence electrons it has a charge of +2. Sulfur wants to gain two electrons to fill its outer shell which makes it -2. This means the Calcium Sulfide is just CaS. To then find the molar mass you can just add the molar mass of calcium to that of sulfer.
40.08g/mol+32.06g/mol=72.14g/mol
40.08g/mol+32.06g/mol=72.14g/mol
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