<h2>The required "options are (II), (III), and (IV)".</h2>
Explanation:
Postulates of Dalton's atomic theory which are scientifically accepted are:
- Atoms are indestructible.
- Compounds are combinations of different atoms.
- A chemical reaction changes the way atoms are grouped together.
Postulates of Dalton's atomic theory which are not accepted scientifically are:
- All atoms of the same elements are identical.
The theory states that the atoms of the same element are identical in every aspect but it is now scientifically proved that the same element should differ in their mass which is known as isotopes.
Answer:
A
Explanation:
Element A has 3 electrons in outermost shell so its valency is 3. It will loose 3 electrons to attain stability, as loss of 3 electrons is easier than gain of 5 electrons.
Valency of B is −2 as it will gain 2 electrons to attain stability and combine with other atom.
Valency of A⟶+3
Valency of B⟶−2
(Refer to Image)
Cross multiply valency of A and B
∴A2B3 compound will be formed.
Magnesium Peroxydisulphate with formula of MgS₂O₈.
<h3><u>Explanation:</u></h3>
The question clearly stands on the concept of molarity and atomic weights.
The atomic weight of magnesium = 24.
The atomic weight of sulphur = 32.
The atomic weight of oxygen = 16.
The amount of magnesium present = 0.248 g
The amount of sulphur present = 0.665 g.
The amount of oxygen present = 1.31g.
So, moles of magnesium present = 0.01 moles.
Moles of sulphur present = 0.02 moles.
Moles of oxygen present = 0.08 moles.
So, mole ratio of the compound as magnesium : sulphur : oxygen = 1:2:8.
So the compound is Magnesium Peroxydisulphate with formula of MgS₂O₈.
Answer:
Thorium-234 option a .......
