1.true or false: calcium tends to gain two electrons during a reaction.(use the periodic table)

false. it will lose two electrons.

false. it will gain six electrons.

true

false. it will lose one electron.
3.a geologist has discovered a rare mineral that can only be found 200 km below the earth’s surface. this mineral’s chemical composition is fetio what kind of mineral is this?

sulfide

native element

nonsilicate oxide

rock-forming oxide
7.what is the density of a mineral sample with a mass of 20 g and a volume of 12 cm?

0.6 g/cm

1.67 g/cm

240 g/cm

20 g/cm
9.how is radioactive decay used to determine the absolute age of rocks?

parent isotopes are compared to daughter isotopes.

daughter isotopes are compared to sister isotopes.

isotopes of different compounds are compared.

radioactive substances are compared to non-radioactive substances.
14.a c=c bond is usually what kind of bond?

polar covalent

hydrogen

ionic

covalent
15.if you were a geologist excavating rocks dating back to precambrian times, what would you expect to find and why?

you would find many fossils because, over time, the rock layers from that period have been very static and have not deformed.

you would find many fossils because the organisms of that time were very diverse.

you would find very few fossils because the dominant organisms were large and had soft shells that decomposed over time.

you would find very few fossils because the dominant organisms were soft-bodied and small.