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
Answer:
6.02 x 10²³ atoms
Explanation:
Given parameters:
Number of moles CaSO₄ = 1 mole
Unknown:
Number of Ca atoms in the given compound = ?
Solution:
The given compound is:
CaSO₄
1 mole of CaSO₄ is made up of 1 mole of Ca atoms
Now;
1 mole of any substance contains 6.02 x 10²³ atoms
1 mole of Ca atoms will also contain 6.02 x 10²³ atoms
3618 is the numbers for the graph
Answer:
<u><em>The correct option is C) the moon takes the same time to rotate and revolve.</em></u>
Explanation:
Scientific experiments have concluded that it takes approximately 23 days for the moon to rotate and also it takes the same duration for the moon to revolve around the Earth. Due to this consistency, the moon appears to be still.
<em>Such synchronization results in the same face of the moon to be directed towards the Earth. Hence, the same craters of the moon will be observed by the scientist every day.</em>
<em></em>
Other options, like option D, is not correct because there will be craters on the other side of the moon too. But as we see the same side of the moon, hence we cannot see the craters present on the other side of the moon.
