Answer:
About 24 hours
Explanation:
Think of it as Earths spin
The Balanced chemical equation for above reaction will be :

The Coefficients will be :
So, Correct option is :
A. 3, 1, 1, 3
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If an electron moves up from the first orbit to the higher energy levels, energy will be absorbed by the electron itself and no emission line produced.
But if it moves from the orbits 6,5,4 and 3 to orbit 2, energy will be released by the electron and different emission lines wll be produced.
Hello friends..
find the MW of HP
calculate the # of mols per 100g of HP
take the # of mols times 6.023 x 10^23 times 2 (2 H per molecule)
Hope it helps you..