Question

The difference between Si/O ratios of K-feldspar and olivine is _________ (answer in two decimal places).

Hint:

Si/O ratios reflect the structure of minerals and how silicon and oxygen atoms are arranged in their crystal lattice. Higher ratios indicate more silicon in relation to oxygen.

Answer 1

Correct Answer: 0.25

Step 1: Understanding Si/O Ratios.
The Si/O ratio refers to the number of silicon atoms per oxygen atom in a mineral's structure. For K-feldspar (KAlSi\(_3\)O\(_8\)), the Si/O ratio is: \[ \text{Si/O ratio for K-feldspar} = \frac{3 \, \text{Si}}{8 \, \text{O}} = 0.375. \] For olivine (Mg\(_2\)SiO\(_4\)), the Si/O ratio is: \[ \text{Si/O ratio for olivine} = \frac{1 \, \text{Si}}{4 \, \text{O}} = 0.25. \] Step 2: Calculate the Difference.
The difference in Si/O ratios between K-feldspar and olivine is: \[ 0.375 - 0.25 = 0.125. \] Step 3: Conclusion.
The difference in Si/O ratios is 0.53 (rounded to two decimal places).