Answer:
This means that Antarctica once had a warmer climate.
Explanation:
Trees usually grow in warm climates, and Antarctica has little to no plant life.
Physical changes happen when you do/mix something that can be reversed. Best example is ripping a paper, you can just tape it back together so it is just an observable thing that changes, which is a physical change. Chemical changes happen when you mix things and they make a new substance and can’t be reversed. The best example of this is the Statue of Liberty, which changed in color due to the chemical change between the oxygen and copper, which created a new substance (rust) which made it green instead of copper.
Sorry for the long answer but hope this helps!
Explanation:
⁶⁵₃₀Ca → ⁶⁵₂₉Sc + ⁿₓH
The reaction above is nuclear reaction.
In a nuclear reaction, the mass number and atomic number must be conserved.
The mass number is the superscript before the atom
Atomic number is the subscript before the atom
Conserving mass number:
65 = 65 + n
n = 0
conserving atomic number:
30 = 29 + x
x = 1
The unknown atom is a positron i.e a positively charged electron: ⁰₁e
⁶⁵₃₀Ca → ⁶⁵₂₉Sc + ⁰₁e
learn more:
Transmutation brainly.com/question/3433940
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