Final answer:
The correct minerals that can be scratched by glass but not by a fingernail, based on the Mohs hardness scale, are Calcite and Topaz. Calcite has a hardness of 3 and Topaz has a hardness of 8 on the Mohs scale.
Step-by-step explanation:
Based on the Mohs hardness scale, to determine the identity of a mineral sample that can be scratched by glass but not by a fingernail, one has to look at the relative hardness of the given options. Since a fingernail has a Mohs hardness of about 2.5, and glass ranges around 5.5 on the scale, the mineral in question would be harder than 2.5 but less than 5.5. Option 2, Calcite, which has a Mohs hardness of 3, can be scratched by glass but not by a fingernail. Option 3, Talc, with a hardness of 1, is too soft as it can be scratched by a fingernail. Therefore, option 2, Calcite, and option 4, Topaz, which has a Mohs hardness of 8, are the correct minerals. Topaz can scratch glass, while Calcite can be scratched by glass but not by a fingernail.
It's important to note that the Mohs scale is a qualitative scale, meaning that the hardness values do not represent a proportional increase in hardness. The scale simply arranges minerals in order of increasing ability to scratch the previous mineral.