Not necessarily, rain needs some mechanism such as instability of vertical air movement..
The charge of Br changed from –1 to 0, therefore it is the
element which is oxidized. Since it is oxidized then Br is also the reducing
agent.
The charge of Mn changed from +4 to +2 therefore it is the
element which is reduced. Since Mn is reduced, then MnO2 is the oxidizing
agent.
The half –reactions are:
Br: 2Br --> Br2 + 2e-
Mn: MnO2 --> Mn2+
First balance oxygen by adding H2O:
MnO2 --> Mn2+ + 2H2O
Then balance hydrogen by adding H+ ions:
4H+ + MnO2 --> Mn2 + 2H2O
Then the appropriate electrons:
4e- + 4H+ + MnO2 --> Mn2 + 2H2O
Multiply the half-reaction of Br by 2 because the half-reaction
of Mn has 4 electrons.
4Br --> 2Br2 + 4e-
Combine the two half reactions and cancel common factors:
4Br- + 4H+ + MnO2 --> 2Br2 + Mn2 + 2H2O
Limestone (CaCO₃) is the second most abundant mineral on Earth after SiO₂. For many uses, it is first decomposed thermally to quicklime (CaO). MgO is prepared similarly from MgCO₃.
AT 871°C CaCO 3 needs about 1 hour for complete decomposition.
<h3>
At what temperature Caco3 decompose to Cao?</h3>
At any temperature higher than 835°C, the value of Δ G ∘ will be negative and the decomposition reaction will be spontaneous.
AT 871°C CaCO 3 needs about 1 hour for complete decomposition.
Calcium carbonate decomposes on heating to give calcium oxide and carbon dioxide.
To learn more about Caco3, refer
brainly.com/question/26187973
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Answer:
Astatine is a halogen with several isotopes that all have short half-lives.
Which of the following combinations of mass number and neutrons are possible as isotopes of astatine? Choose one or more:
i) A = 211, n = 127
ii) A = 210, n = 125
iii) A = 220, n = 134
iv) A = 207, n = 122
v) A = 209, n = 124
Explanation:
The mass number is the sum of the number of protons and the number of neutrons in an atom.
Atomic number of At(astatine ) =85
That means it has --- 85protons.
Its mass number A=210
Hence, the number of neutrons in At are:
Second option:
ii) A=210 , n=125 is the answer.
