Question

Jess scratches an unknown mineral with topaz, which has a Mohs hardness of 8. Topaz leaves a scratch on the unknown mineral. The unknown mineral _____.

Answer 1

The unknown mineral has to have a smaller hardness number (meaning it’s softer). It’s hardness can be between 1-7. Some minerals it could be (and their hardness) are:
quartz-7
orthoclase-6
apatite-5
fluorite-4
calcite-3
gypsum-2
talc-1