Answer:
Enthalpy change = 74.36 kJ
Explanation:
Enthalpy change is defines as the heat absorbed or evolved during a chemical reaction at constant pressure and volume
Reaction:
H2O(l) --> H2O(g)
DHr = mCsDT
Where m is the mass of water
Cs is the specific heat capacity
DT is the temperature difference
= 31.6 * 4.18 * (25 - 3.2)
= 2879.518 J
DHvap = 44kJ/mol
Moles of water = mass/molecular weight
Molecular weight = (1*2) + 16
= 18g/mol
Moles of water = 31.6/18
= 1.756 moles
DHvap = 44 * 1.756
= 77.244kJ
DH = DHproduct - DHreactant
DHproduct = DHvap = 77.24kJ
DHreactant = DHr = 2879.518J = 2.880kJ
= 77.24 - 2.880
DH = 74.36kJ
Enthalpy change = 74.36 kJ
Answer:
I believe C
Explanation:
Saying it always does one thing or another is mostly not the case. When it comes to biodiversity, there can be positive impacts! But an ecosystem is affected by everything in it's biodiversity.
<u>Answer:</u> The pH of the solution is 9.71
<u>Explanation:</u>
1 mole of NaOH produces 1 mole of sodium ions and 1 mole of hydroxide ions.
We are given:
pOH of the solution = 7.2
To calculate the pH of the solution, we need to determine pOH of the solution. To calculate pOh of the solution, we use the equation:
![pOH=-\log[OH^-]](https://tex.z-dn.net/?f=pOH%3D-%5Clog%5BOH%5E-%5D)
We are given:
![[OH^-]=5.09\times 10^{-5}M](https://tex.z-dn.net/?f=%5BOH%5E-%5D%3D5.09%5Ctimes%2010%5E%7B-5%7DM)
Putting values in above equation, we get:
To calculate pH of the solution, we use the equation:
Hence, the pH of the solution is 9.71
Moles = (6.74*10^23)/(6.02*10^23) =1.119 moles
1.119*44.09=49.36g
Neutrons don’t carry an electrical charge, meaning that adding or subtracting them from the nucleus will not change the electrical charge of the nucleus of an atom. But, adding/removing neutrons changes the mass of the nucleus. This is how isotopes are formed.
