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Gwar [14]
3 years ago
15

Limestone stalactites and stalagmites are formed in caves by the following reaction: Ca2 (aq) 2HCO−3(aq)→CaCO3(s) CO2(g) H2O(l)

If 1 mol of CaCO3 forms at 298 K under 1 atm pressure, the reaction performs 2.47 kJ of P−V work, pushing back the atmosphere as the gaseous CO2 forms. At the same time, 38.65 kJ of heat is absorbed from the environment. What is the value of ΔE for this reaction
Chemistry
1 answer:
Vesna [10]3 years ago
6 0

Answer : The value of \Delta E for this reaction is 36.18 kJ

Explanation :

First law of thermodynamic : It states that the energy can not be created or destroyed, it can only change or transfer from one state to another state.

As per first law of thermodynamic,

\Delta E=q+w

where,

\Delta E = internal energy  of the system

q = heat added or rejected by the system

w = work done

As we are given that:

q = 38.65 kJ

w = -2.47 kJ (system work done on surrounding)

Now put all the given values in the above expression, we get:

\Delta E=38.65kJ+(-2.47kJ)

\Delta E=36.18kJ

Therefore, the value of \Delta E for this reaction is 36.18 kJ

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When the magnesium strip is burned, this is a chemical reaction. The problem is that we only measure the mass of one of the substances involved in the reaction which is the magnesium strip, which makes it seem like the mass has increased. Actually, while burning, the magnesium combines with oxygen in the air. This oxygen was present before the reaction, we just did not measure it. And after the reaction it is present in the form of product. But the mass is still conserved.

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<h3>What do we know about the process of dissolution?</h3>

A solute can dissolve in a solvent in a solid, liquid, or gaseous phase to create a solution through the process of dissolution. Solubility. The greatest amount of a solute that may dissolve in a solvent at a particular temperature is known as its solubility. The solution is said to as saturated when the maximum amount of solute is present.

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