What is the specific heat of coffee?

What is the specific heat of coffee?

Using coffee (specific heat capacity of 3.98 x 10^3 J/kg °C) calculate the increase in mass if you raised the temperature of a 353 g cup of coffee from 34° C to 97°C.

What is meant by a spontaneous process?

A spontaneous process is capable of proceeding in a given direction without needing to be driven by an outside source of energy. An endergonic reaction (also called a nonspontaneous reaction) is a chemical reaction in which the standard change in free energy is positive and energy is absorbed.

What increases in a spontaneous process?

The second law of thermodynamics states that a spontaneous process increases the entropy of the universe, Suniv > 0. A negative value for ΔG indicates a spontaneous process; a positive ΔG indicates a nonspontaneous process; and a ΔG of zero indicates that the system is at equilibrium.

How do you know when a reaction is spontaneous?

Sum of temperature times delta S must be over 58.1(total of delta H) so that gibbs free energy is 0 or less . Thus divide 58.2 by 0.165 to find energy needed for delta G =0 any temp above this will result in a negative (spontaneous reaction).

How do you know if a reaction is feasible?

For a reaction to be feasible at a given temperature, it must happen spontaneously, which means no extra energy needs to be put in for the reaction to occur. To find out whether a reaction is feasible, you can calculate the Gibbs free energy change (ΔG) for that particular reaction.

Why does Gibbs free energy decrease with temperature?

Free Energy (G) can either increase or decrease for a reaction when the temperature increases. It depends on the entropy (S) change. In this case dS will be positive and -TdS becomes more negative when the temperature goes up. So the numeric value of the free energy becomes smaller.

How does Gibbs free energy change with temperature?

Gibbs free energy (G) is also known as free energy or Gibbs energy. The sign of ΔGreaction does not change with changes in temperature if the sign of ΔH is the opposite of the sign of ΔS: (a) ΔH < 0 and ΔS > 0 then ΔG < 0 and reaction is spontaneous at any temperature.

Is Gibbs free energy dependent on temperature?

(1) The temperature dependence of the Gibbs free energy (The Gibbs-Helmholtz equation.) The temperature dependence of G is governed by the following relationship: Then sharpness of the decrease of G decreases with temperature at constant pressure is determined by the entropy of the system.

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