Answer:
131.5 kJ
Explanation:
Let's consider the following reaction.
CaCO₃(s) → CaO(s) + CO₂(g)
First, we will calculate the standard enthalpy of the reaction (ΔH°).
ΔH° = 1 mol × ΔH°f(CaO(s)) + 1 mol × ΔH°f(CO₂(g)
) - 1 mol × ΔH°f(CaCO₃(s)
)
ΔH° = 1 mol × (-634.9 kJ/mol) + 1 mol × (-393.5 kJ/mol) - 1 mol × (-1207.6 kJ/mol)
ΔH° = 179.2 kJ
Then, we calculate the standard entropy of the reaction (ΔS°).
ΔS° = 1 mol × S°(CaO(s)) + 1 mol × S°(CO₂(g)
) - 1 mol × S°(CaCO₃(s)
)
ΔS° = 1 mol × (38.1 J/mol.K) + 1 mol × (213.8 J/mol.K) - 1 mol × (91.7 J/mol.K)
ΔS° = 160.2 J/K = 0.1602 kJ/K
Finally, we calculate the standard Gibbs free energy of the reaction at T = 25°C = 298 K.
ΔG° = ΔH° - T × ΔS°
ΔG° = 179.2 kJ - 298 K × 0.1602 kJ/K
ΔG° = 131.5 kJ
 
        
             
        
        
        
Answer:
There are 79 protons in the nucleus of one Gold atom.
Explanation:
The number of protons of any given atom/element can be determined by the atomic number of the specific element, which is found on the periodic table.
 
        
             
        
        
        
 A plant's circulatory system is the way for a plant to get carbon dioxide and nutrients to every cell in its system. It is also the way for a plant to get rid of toxins and waste from its system. In a plant's circulatory system, the nutrients a plant needs to survive travels upwards from the roots of the plan to the rest of it's system, and the toxins and waste is secreted from its extremeties located above the ground.
HOPE THIS HELPS 
 
        
             
        
        
        
When you heat an atom, some of its electrons are "excited* to higher energy levels. When an electron drops from one level to a lower energy level, it emits a quantum of energy. ... The different mix of energy differences for each atom produces different colours. Each metal gives a characteristic flame emission spectrum.
        
             
        
        
        
Answer:
d. compound
Explanation:
compound and elements are pure substances