Question
A geologist determines that a sample of a mineral can't be scratched by a steel nail but can be scratched by a masonry drill bit. Based on this information, the sample mineral has to be softer than
Question 1 options:
A)
apatite.
B)
orthoclase.
C)
corundum.
D)
fluorite.
Question 1 options:
A)
apatite.
B)
orthoclase.
C)
corundum.
D)
fluorite.
Answers
GPT-4o mini
To determine the hardness of the mineral based on the information that it can't be scratched by a steel nail but can be scratched by a masonry drill bit, we can refer to the Mohs scale of mineral hardness:
- Steel has a hardness of about 5.5 (it is usually able to scratch minerals that have a hardness of less than 5.5).
- Masonry drill bits typically are harder than steel and can scratch materials with hardness around 6 or higher.
Given this information:
- The mineral being scratched by the masonry drill bit indicates that it is softer than the bit (greater than 6).
- The mineral not being scratched by the steel nail indicates that its hardness is less than 5.5.
From the options given:
- A) Apatite (hardness 5)
- B) Orthoclase (hardness 6)
- C) Corundum (hardness 9)
- D) Fluorite (hardness 4)
Since the mineral can be scratched by the masonry drill bit (hardness >6) and cannot be scratched by a steel nail (hardness <5.5), then we need to consider the hardness of the available minerals:
- Apatite (5) is softer than the mineral
- Orthoclase (6) is about the same hardness as steel and cannot be scratched by it
- Corundum (9) is much harder than the mineral
- Fluorite (4) is also softer than the mineral
The only mineral that fits the criteria (softer than the masonry drill bit but harder than the steel nail) is **Apatite (hardness 5)**.
Therefore, the answer is:
**A) apatite.**
- Steel has a hardness of about 5.5 (it is usually able to scratch minerals that have a hardness of less than 5.5).
- Masonry drill bits typically are harder than steel and can scratch materials with hardness around 6 or higher.
Given this information:
- The mineral being scratched by the masonry drill bit indicates that it is softer than the bit (greater than 6).
- The mineral not being scratched by the steel nail indicates that its hardness is less than 5.5.
From the options given:
- A) Apatite (hardness 5)
- B) Orthoclase (hardness 6)
- C) Corundum (hardness 9)
- D) Fluorite (hardness 4)
Since the mineral can be scratched by the masonry drill bit (hardness >6) and cannot be scratched by a steel nail (hardness <5.5), then we need to consider the hardness of the available minerals:
- Apatite (5) is softer than the mineral
- Orthoclase (6) is about the same hardness as steel and cannot be scratched by it
- Corundum (9) is much harder than the mineral
- Fluorite (4) is also softer than the mineral
The only mineral that fits the criteria (softer than the masonry drill bit but harder than the steel nail) is **Apatite (hardness 5)**.
Therefore, the answer is:
**A) apatite.**