Answer:
0
Explanation:
Since HI is a strong acid, the amoung of Hydrogen ions produced by it will be the same molar as the reactant. The negative log of the concentration will reveal that the pH is 0.
The Erlenmeyer Flask was <span>introduced in 1861 by German chemist </span>Emil Erlenmeyer and is shaped like a cone. This has a triangular shape and mouth wide for it to be easier to pour and store liquids. The Volumetric flask<span> is used for preparing liquids with volumes of high precision. It has a </span>pear-shaped body and a long neck with a circumferential fill line. The Filter Flask is also known as the <span>A Büchner </span><span>flask. It is like the Erlenmeyer but this one is thick-walled and has a special arm in the side. It is used for filtering liquid. </span>
Answer : The change in internal energy is, 900 Joules.
Solution : Given,
Heat given to the system = +1400 J
Work done by the system = -500 J
Change in internal energy is equal to the sum of heat energy and work done.
Formula used :

where,
= change in internal energy
q = heat energy
w = work done
As per question, heat is added to the system that means, q is positive and work done by the system that means, w is negative.
Now put all the given values in the above formula, we get

Therefore, the change in internal energy is 900 J.
The change in internal energy depends on the heat energy and work done. As we will change in the heat energy and work done, then changes will occur in the internal energy. Hence, the energy is conserved.