You could ask whether the black crust is a new substance formed from silver underwent a chemical change because a chemical change produces a new substance.
Answer:
The answer to your question is 0.79 moles of SnCl₂
Explanation:
Data
moles of SnCl₂ = ?
mass of FeCl₃ = 85.3 g
excess Sn
Balanced chemical reaction
2 FeCl₃ + 3 Sn ⇒ 3 SnCl₂ + 2 Fe
Process
1.- Convert the mass of FeCl₃ to moles
Molar mass of FeCl₃ = 56 + (35.5 x 3)
= 56 + 106.5
= 162.5 g
Use proportions to find the moles of FeCl₃
162.5 g -------------------- 1 mol
85.3 g ------------------- x
x = (85.3 x 1) / 162.5
x = 0.525 moles
2.- Find the number of moles SnCl₂
2 moles of FeCl₃ ----------------- 3 moles of SnCl₂
0.525 moles ----------------- x
x = (0.525 x 3) / 2
x = 0.79 moles of SnCl₂
Since the scientists found a fossil from a modern day badger from the Holocene geologic epoch, the badger would be mostly the same, as this is the most recent, and still on going geologic epoch, starting from little less than 12,000 years ago. If the scientist wants to find a fossilized remains of earlier badgers, thus of their ancestors from the Pleistocene epoch, than the scientist should dig deeper. Not a lot deeper though, as the layers of rock from the Pleistocene are just bellow the layers of rock from the Holocene, as the Pleistocene is the second youngest geologic epoch, being the predecessor of the Holocene.
If X is an equivalent base to H₂O
HX is an equivalent acid to H₃O⁺
HX is a stronger acid than H₃O⁺
HX is not an acid
X⁻ is a stronger base than H₂O
HX is a weaker acid than H₃O⁺
X⁻ is a weaker base than H₂O
X⁻ is not a base.
The correct response or this is
X⁻ is a stronger base than H₂O
HX is a weaker acid than H₃O⁺
