Vertical-horizon.
If neither of them are it then it’s columns
<h2>Answer:</h2>
Option A is correct
Adding an enzyme to decrease the activation energy of the reaction
<h2>Explanation:</h2>
Enzymes are the biological catalyst. They are proteins in nature. They are naturally found in humans,animals,micro-organisms,plants etc. They catalyze the chemical reactions by lowering activation energy and without being consumed in it.
Explanation :
In thermodynamics, a system is region or part of space which is being studied and observed while the surrounding is the region or space around the system which interacts with the system.
Here in the experiment ,system which is observed is reaction or changes when citric acid and sodium bicarbonate are mixed together. And the mixing is carried out in the calorimeter which serves as a surrounding around the system.
The reason behind the using the calorimeter is measure the energy change occurring during the reaction.
We will see that the volume of the unit cell is 144,070,699.06 pm^3
<h3>
How to get the volume of a body-centered cubic unit cell?</h3>
In a body-centered cubic unit cell, the side length of the cube is given as:
Where R is the radius of the atom.
And the volume of a cube is the side length cubed, then we can see that the volume of our cube will be:
Solving that we get:
This is the approximated volume of the unit cell.
If you want to learn more about unit cell structures, you can read:
brainly.com/question/13110055
