Questions: This is the chemical formula for talc (the main ingredient in talcum powder): Mg3(Si2O5)2(OH)2 An analytical chemist has determined by measurements that there are 0.0251 moles of silicon in a sample of talc. How many moles of hydrogen are in the sample? Be sure your answer has the correct number of significant digits. mol

This is the chemical formula for talc (the main ingredient in talcum powder):
Mg3(Si2O5)2(OH)2

An analytical chemist has determined by measurements that there are 0.0251 moles of silicon in a sample of talc. How many moles of hydrogen are in the sample?
Be sure your answer has the correct number of significant digits.
mol

Transcript text: This is the chemical formula for talc (the main ingredient in talcum powder): \[ \mathrm{Mg}_{3}\left(\mathrm{Si}_{2} \mathrm{O}_{5}\right)_{2}(\mathrm{OH})_{2} \] An analytical chemist has determined by measurements that there are 0.0251 moles of silicon in a sample of talc. How many moles of hydrogen are in the sample? Be sure your answer has the correct number of significant digits. $\square$ mol $\square$

Solution

Solution Steps

Step 1: Determine the Mole Ratio of Silicon to Hydrogen in Talc

The chemical formula for talc is $\mathrm{Mg}_{3}\left(\mathrm{Si}_{2} \mathrm{O}_{5}\right)_{2}(\mathrm{OH})_{2}$. This formula indicates that each formula unit of talc contains:

2 moles of silicon ($\mathrm{Si}$)
2 moles of hydroxide ($\mathrm{OH}$), which means 2 moles of hydrogen ($\mathrm{H}$) because each $\mathrm{OH}$ contains 1 hydrogen atom.

Step 2: Calculate the Moles of Hydrogen

Given that there are 0.0251 moles of silicon in the sample, we use the mole ratio from the formula to find the moles of hydrogen. Since there are 2 moles of hydrogen for every 2 moles of silicon, the moles of hydrogen will be equal to the moles of silicon:

\[ \text{Moles of hydrogen} = \text{Moles of silicon} = 0.0251 \text{ moles} \]