Answer: There are 20 protons neutrons in the atom
Answer:
The entropy change for a real, irreversible process is equal to <u>zero.</u>
The correct option is<u> 'c'.</u>
Explanation:
<u>Lets look around all the given options -:</u>
(a) the entropy change for a theoretical reversible process with the same initial and final states , since the entropy change is equal and opposite in reversible process , thus this option in not correct.
(b) equal to the entropy change for the same process performed reversibly ONLY if the process can be reversed at all. Since , the change is same as well as opposite too . Therefore , this statement is also not true .
(c) zero. This option is true because We generate more entropy in an irreversible process. Because no heat moves into or out of the surroundings during the procedure, the entropy change of the surroundings is zero.
(d) impossible to tell. This option is invalid , thus incorrect .
<u>Hence , the correct option is 'c' that is zero.</u>
Answer: Th enthalpy of combustion for the given reaction is 594.244 kJ/mol
Explanation: Enthalpy of combustion is defined as the decomposition of a substance in the presence of oxygen gas.
W are given a chemical reaction:



To calculate the enthalpy change, we use the formula:

This is the amount of energy released when 0.1326 grams of sample was burned.
So, energy released when 1 gram of sample was burned is = 
Energy 1 mole of magnesium is being combusted, so to calculate the energy released when 1 mole of magnesium ( that is 24 g/mol of magnesium) is being combusted will be:

Answer: 147 mL
Explanation:
<u>Given:</u>
Molarity of the sodium bromide (NaBr) solution (M1) = 1.75 M
Volume of the solution (V1) = 84 mL
Molarity of the diluted NaBr solution (M2) = 1 M
Using the dilution formula to solve for V2:

Therefore, the new volume of the solution is 147 mL