Answer:
Na2SO3 + H2O2 = Na2SO4 + H2O
The much of the sample that would remain unchanged after 140 seconds is 2.813 g
Explanation
Half life is time taken for the quantity to reduce to half its original value.
if the half life for Scandium is 35 sec, then the number of half life in 140 seconds
=140 sec/ 35 s = 4 half life
Therefore 45 g after first half life = 45 x1/2 =22.5 g
22.5 g after second half life = 22.5 x 1/2 =11.25 g
11.25 g after third half life = 11.25 x 1/2 = 5.625 g
5.625 after fourth half life = 5.625 x 1/2 = 2.813
therefore 2.813 g of Scandium 47 remains unchanged.
<span>Photolysis and hydrolysis. These are two methods that can be used to break down a compound into simpler substances and smaller units.
Water which is used to break the bonds of molecules and split molecules is used from hydrolysis. Hydrolysis is made of three types which include;
1. salt hydrolysis.
2. acid hydrolysis.
3. Base hydrolysis.
Photolysis is well known to use energy from light to split the molecule and the same energy is referred to as photons which are used to break builds of molecules.</span>
The smallest unit that can exist as an element and still have proprieties of that element is an Atom<span />