Structure of a-chloro-b-methylbutyric acid (2-chloro-3-methylbutyric acid is attached below.
The structure was drawn using following information.
1) First, the parent chain was identified. The parent chain is containing four carbon atoms, also, this chain belongs to carboxylic acid as the compound name ends with Butyric acid i.e. butyr (Butane) -ic acid (carboxylic acid).
2) Secondly, the positions of substituents were assigned by using the rule which sates that the numbering in carboxylic acid must satrt from the carbonyl carbon. Therefore, the carbon which is attached to carbonyl carbon is named as alpha (2nd position) and carbon next to alpha carbon is named as beta carbon (3rd position). Hence, we add chlorine atom on 2nd carbon next to carbonyl group and methyl group at 3rd carbon with respect to carbonyl carbon.
Answer:
Helium is created from hydrogen in the sun's core.
Four hydrogen-1 nuclei fuse to produce
- one helium-4 nucleus, two neutrons,
- two positrons, and
- two electron neutrinos.
Explanation:
Step One:
.
Two hydrogen-1 nuclei fuse. One proton will convert to a neutron. The products will be
- one hydrogen-2 nucleus,
- one positron, and
- one electron neutrino.
Step Two:
.
There are plenty of hydrogen-1 nuclei available in the core of the sun. The hydrogen-2 nucleus from step one will fuse with a hydrogen-1 nucleus. The product is
Step Three
.
Two helium-3 nuclei from step two react with each other. The products are:
- one helium-4 nucleus, and
- two hydrogen-1 nuclei.
The overall reaction will be:
.

In other words, hydrogen nuclei in the core of the sun fuse together to form helium.
It is difficult to measure the enthalpy change of hydration accurately in a direct way because the hydration process can't be controlled directly. Instead, anhydrous and hydrated copper(II) sulfate can be dissolved in water. Each 'route' produces a solution of hydrated copper(II) sulfate.