Answer:
Volcanoes absorbed water vapor from the atmosphere and made the planet very dry and difficult to live
on
Answer:
Yes, it's an exothermic reaction, which means that energy is being released, thus it is a chemical reaction.
Explanation:
Answer:
a) CaF₂.
b) 7.81g of CaF₂ are present.
Explanation:
a) The calcium ion has as charge Ca²⁺ and fluoride ion is F⁻, that means formula unit is:
CaF₂
b) 1 molecule of CaF₂ contains 2 anions, F⁻. Thus, the moles of CaF₂ is:
1.2x10²³ anions * (1 moleculeCaF₂ / 2 anions) = 6x10²² molecules of CaF₂
6.022x10²³ molecules = 1mol:
6x10²² molecules of CaF₂ * (1mol / 6.022x10²³molecules) = 0.10 moles CaF₂.
1 mole of CaF₂ has a mass of 78.07g:
0.10 moles CaF₂ * (78.07g / mol) =
7.81g of CaF₂ are present
Both noticed that different atoms gives different colours of light when they are exposed to flame.
