Question

An Olympic medal contains 71.5% of gold by mass. How much gold could be extracted from a medal that weighs 115 grams? 1. 82.2 mol 2. 0.817 mol 3. 0.417 mol 4. 31.7 mol 5. 14.1 mol 6. 1.33 mol

Answer 1

To extract gold from a 115-gram medal with 71.5% gold content, one would obtain approximately 0.417 moles of gold by dividing the mass of gold (82.225 grams) by the molar mass of gold (196.97 g/mol).

Step-by-step explanation:

To calculate how much gold could be extracted from a medal that weighs 115 grams with a 71.5% gold composition by mass, we first need to find the mass of the gold in the medal:

• Mass of gold = 71.5% of total mass of the medal = 0.715 × 115 grams = 82.225 grams
• To find the number of moles of gold, we use the formula: number of moles = mass of gold (in grams) / molar mass of gold (in g/mol).
• The molar mass of gold (Au) is 196.97 g/mol, according to the periodic table.
• Number of moles of gold = 82.225 grams / 196.97 g/mol = 0.417 moles (approximately).

Therefore, the amount of gold that could be extracted from a medal weighing 115 grams is approximately 0.417 moles of gold.

Answer 2

0.417 mol could be extracted from a medal that weighs 115 grams

Step-by-step explanation:

Our Olympic medal weighs 115 g and we know that 71.5% is gold so how much from this medal is gold?

100 % ____ 115 g

71,5 % ____ 82.22 g

Molar mass of Au is 196.97 g/m

Mass / Molar mass = Moles

82.22 g / 196.97 g/m = 0.417 moles