Answer:
25% thorium will left after 50 days.
Explanation:
Half life:
A nuclear half is the time period of radioactive material in which its amount remain halved.
In given question it is stated that the half life thorium-234 is 25 days. Which means after passing the 25 days the amount of thorium must be halved of original amount.
For example,
If the original concentration was 100%, than after 25 days it will be 50%.
After 50 days amount of thorium left:
Number of half life = T (elapsed) / T half life
Number of half life = 50/25
Number of half life = 2
At first half life amount of thorium left = 100/2 = 50
After second half life amount of thorium left = 50/2 = 25
Total amount decayed = 50+25 = 75
Amount left after 50 days = 100-75 = 25
25% thorium will left after 50 days.
Carbonic acid
dissolves limestone and other rocks. This is an example of chemical erosion. An
example is in the caves. Caves are formed where rainwater as it falls
through the atmosphere absorbs carbon dioxide. The carbon dioxide makes the
rain acidic to react it with the limestone bedrock. The rainwater is absorbed
by the soil into the ground. Then as it enters through the soil, the rainwater
will absorb more carbon dioxide that is produced by the decomposers. The carbon
dioxide with water reacts to form carbonic acid. The carbonic acid will react
to limestone and dissolves it slowly. As the space become larger, water can
enter into it.
Answer : The value of
for the reaction is -959.1 kJ
Explanation :
The given balanced chemical reaction is,

First we have to calculate the enthalpy of reaction
.

![\Delta H^o=[n_{H_2O}\times \Delta H_f^0_{(H_2O)}+n_{SO_2}\times \Delta H_f^0_{(SO_2)}]-[n_{H_2S}\times \Delta H_f^0_{(H_2S)}+n_{O_2}\times \Delta H_f^0_{(O_2)}]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo%3D%5Bn_%7BH_2O%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28H_2O%29%7D%2Bn_%7BSO_2%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28SO_2%29%7D%5D-%5Bn_%7BH_2S%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28H_2S%29%7D%2Bn_%7BO_2%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28O_2%29%7D%5D)
where,
= enthalpy of reaction = ?
n = number of moles
= standard enthalpy of formation
Now put all the given values in this expression, we get:
![\Delta H^o=[2mole\times (-242kJ/mol)+2mole\times (-296.8kJ/mol)}]-[2mole\times (-21kJ/mol)+3mole\times (0kJ/mol)]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo%3D%5B2mole%5Ctimes%20%28-242kJ%2Fmol%29%2B2mole%5Ctimes%20%28-296.8kJ%2Fmol%29%7D%5D-%5B2mole%5Ctimes%20%28-21kJ%2Fmol%29%2B3mole%5Ctimes%20%280kJ%2Fmol%29%5D)

conversion used : (1 kJ = 1000 J)
Now we have to calculate the entropy of reaction
.

![\Delta S^o=[n_{H_2O}\times \Delta S_f^0_{(H_2O)}+n_{SO_2}\times \Delta S_f^0_{(SO_2)}]-[n_{H_2S}\times \Delta S_f^0_{(H_2S)}+n_{O_2}\times \Delta S_f^0_{(O_2)}]](https://tex.z-dn.net/?f=%5CDelta%20S%5Eo%3D%5Bn_%7BH_2O%7D%5Ctimes%20%5CDelta%20S_f%5E0_%7B%28H_2O%29%7D%2Bn_%7BSO_2%7D%5Ctimes%20%5CDelta%20S_f%5E0_%7B%28SO_2%29%7D%5D-%5Bn_%7BH_2S%7D%5Ctimes%20%5CDelta%20S_f%5E0_%7B%28H_2S%29%7D%2Bn_%7BO_2%7D%5Ctimes%20%5CDelta%20S_f%5E0_%7B%28O_2%29%7D%5D)
where,
= entropy of reaction = ?
n = number of moles
= standard entropy of formation
Now put all the given values in this expression, we get:
![\Delta S^o=[2mole\times (189J/K.mol)+2mole\times (248J/K.mol)}]-[2mole\times (206J/K.mol)+3mole\times (205J/K.mol)]](https://tex.z-dn.net/?f=%5CDelta%20S%5Eo%3D%5B2mole%5Ctimes%20%28189J%2FK.mol%29%2B2mole%5Ctimes%20%28248J%2FK.mol%29%7D%5D-%5B2mole%5Ctimes%20%28206J%2FK.mol%29%2B3mole%5Ctimes%20%28205J%2FK.mol%29%5D)

Now we have to calculate the Gibbs free energy of reaction
.
As we know that,

At room temperature, the temperature is 500 K.


Therefore, the value of
for the reaction is -959.1 kJ
Answer:
Electrical energy = 130000000 J and Heat energy = 520000000 J
Explanation:
Multiply the amount of joules from the last question (650000000) by .20 and .80. (Which are the percentages)
Explanation:
While both developed and developing countries have contributed to global environmental problems, developed countries with 85% percent of the gross world product and 23% of its population account for the largest part of mineral and fossil-fuel consumption, resulting in significant environmental impacts