C can be the only correct answer - 6.023 x 10^23 is the amount of molecules in a mol of an element. 4.5 x 6.023 x 10^23 can not equal anything but C.
4.5 x 6.023 x 10^23 = 2.71035 x 10^24
Answer: solid chemicals in waterharden and form rocks
Explanation:
Do you mean "deciding when the continents shifted"? If so, the fossils of fish and other animals found in mountain belts show when water was surrounding a certain landmass. From here scientists can determine when this land mass separated.
Answer:
5.35×10²⁴ atoms of Li
Explanation:
To solve this we apply this rule of three:
We know that 1 mol contains 6.02×10²³ atoms
Therefore, 8.9 moles must contain (8.9 . 6.02×10²³) / 1 = 5.35×10²⁴ atoms
One mol is the amount of substance containing as many elemental entities as atoms, which are contained in 12 g of the C¹² isotope
In conclussion 6.02×10²³ atoms of C¹² isotope weighs 12 g