For the first question:
Valuable ore deposits and gem crystals are often associated
with igneous intrusions. So for this question the correct option is option “d”.
An example like the Pegmatite’s, which are a form of igneous intrusions, is
responsible for the creation of variety of gems like topaz and tourmaline.
For the second question:
For this specific question, option “c” seems to be the
correct option. Weathering, deposition, compaction, cementation are the
possible sequence that leads to the formation of sedimentary rocks.
When we have this balanced equation for a reaction:
Fe(OH)2(s) ↔ Fe+2 + 2OH-
when Fe(OH)2 give 1 mole of Fe+2 & 2 mol of OH-
so we can assume [Fe+2] = X and [OH-] = 2 X
when Ksp = [Fe+2][OH-]^2
and have Ksp = 4.87x10^-17
[Fe+2]= X
[OH-] = 2X
so by substitution
4.87x10^-17 = X*(2X)^2
∴X^3 = 4.8x10^-17 / 4
∴the molar solubility X = 2.3x10^-6 M
Clean? I’m pretty sure not sure what it means but.
Answer:
butyne
Explanation:
alkane, alkene, and alkyne are all examples of hydrocarbons.
butyne = alkyne
The answer from this questions is the letter
B. He should not use his opinions as evidence.
