Answer:
= 25.05°C
Explanation:
Given:
the value of ΔHcomb (heat of combustion) for dimethylphthalate (C10H10O4) is = 4685 kJ/mol.
mass = 0.905g of dimethylphthalate
molar mass = 194.18g dimethylphthalate
number of moles of dimethylphthalate = ???
= 21.5°C
= 6.15 kJ/°C
= ???
since we have our molar mass and mass of dimethylphthalate ;we can determine the number of moles as;
0.905g of dimethylphthalate × 
number of moles of dimethylphthalate = 0.000466 moles
Heat released = moles of dimethylphthalate × heat of combustion
= 0.000466 moles × 4685 kJ
= 21.84 kJ
∴ Heat absorbed by the calorimeter = 
21.84 kJ =6.15 kJ/°C 
21.84 KJ = 
21.84 KJ = 
- 132.225 kJ
21.84 KJ + 132.225 kJ =
154.065 kJ =
= 
=25.05°C
<u>Answer:</u>
The correct answer option is B) 2.0 M.
<u>Explanation:</u>
We are given the number of grams of NaOH (Sodium Chloride) which are dissolved in 750 milliliters of water and we are to find its molarity.
We know the formula of molarity:
<em>Molarity = (mass * 1000) / (volume * molecular mass) </em>
Volume = 750 ml = 750 cm
Molecular mass = 40
Mass = 60 grams
Substituting these values in the above formula:
Molarity = 
= 2.0 M
Answer: I am confident the answer is B
Explanation:
forgive me if im wrong
Answer:
Explanation:Although the term is quite new, our connection to nature is not. We depend on nature for our survival - without healthy ecosystems, our drinking water isn’t clean nor is the air we breathe. We also enjoy nature... studies show that people who spend time in nature tend to be happier than those that don’t. It can even act as a natural anti-depressant. With industry and urban sprawl expanding at unprecedented rates, Ecosystem Services attempt to translate the benefits we receive from nature into economic terms so we can better understand the trade-offs we are making between nature and industrial development.
Answer: Option (B) is the correct answer.
Explanation:
Degree of randomness of the molecules of a substance is known as entropy. More is the kinetic energy between the molecules of a substance more will be the degree of randomness.
Therefore, when a substance is present in a gaseous state then it has the maximum entropy. In liquid state, molecules are closer to each other so, there is less randomness between them.
On the other hand, in solid state molecules are much more closer to each other as they arr held by strong intermolecular forces of attraction. Therefore, they have very less entropy.
- When liquid water is formed from gaseous hydrogen and oxygen molecules then gas is changing into liquid. So, there is decrease in entropy.
- When
decomposes then the reaction will be as follows.
Since, 1 mole is producing 2 moles. This means that degree of randomness is increasing as both the molecules are present in gaseous form.
- In formation of a precipitate, aqueous solution is changing into solid state. Hence, degree of randomness is decreasing.
- Rusting of iron also leads to the formation of solid as it forms
.
Thus, we can conclude that decomposition of gas to 
gas is the process that is expected to have an increase in entropy.
