Answer:

Explanation:
Hess's Law of Constant Heat Summation states that if a chemical equation can be written as the sum of several other chemical equations, the enthalpy change of the first chemical equation is equal to the sum of the enthalpy changes of the other chemical equations. Thus, the reaction that involves the conversion of reactant A to B, for example, has the same enthalpy change even if you convert A to C, before converting it to B. Regardless of how many steps it takes for the reactant to be converted to the product, the enthalpy change of the overall reaction is constant.
With Hess's Law in mind, let's see how A can be converted to 2C +E.
(Δ
) -----(1)
Since we have 2B, multiply the whole of II. by 2:
(2Δ
) -----(2)
This step converts all the B intermediates to 2C +2D. This means that the overall reaction at this stage is
.
Reversing III. gives us a negative enthalpy change as such:
(-Δ
) -----(3)
This step converts all the D intermediates formed from step (2) to E. This results in the overall equation of
, which is also the equation of interest.
Adding all three together:
(
)
Thus, the first option is the correct answer.
Supplementary:
To learn more about Hess's Law, do check out: brainly.com/question/26491956
Answer:
subtract
Explanation:
To find the net force of two bodies going in opposite directions, we must subtract the forces this is because they are not additive forces.
- The net force is the resultant force acting on a body.
- This resultant force is the single force that will produce the same effects as all given forces.
- When forces are directed oppositely on a body, they are subtracted from each other to find the net force.
It is a bit like a video game because when you dumb it down, it's basically a small robotic thing that is controlled by a controller. In video games, you have an avatar being controlled inside a game using a gamepad, in surgery you have a little machine inside of a person's body being controlled using a computer.
Answer:
because he would've not known properly about it!
Answer: 4.4 x 10^-7
Explanation:
The dissociation equation for this reaction is:
MgCO3 (s) → Mg+2 (aq) + CO3-2 (aq)
(Here 0.08 >>> x )

So the solubility MgCO₃ in a solution that containing 0.080 M Mg²⁺ is 4.4 x 10^-7