Answer:
B. Lower than 100 °C because hydrogen sulfide has dipole-dipole interactions instead of hydrogen bonding.
Explanation:
Intermolecular bonds exists between seperate molecules or units. Their relative strength determines many physical properties of substances like state of matter, solubility of water, boiling point, volatility, viscosity etc. Examples are Van der waals forces, hydrogen bonds and crystal lattice forces.
In hydrogen sulfide, the intermolecular bond is a dipole-dipole attraction which is a type of van der waals attraction. It occurs as an attraction between polar molecules. These molecules line such that the positive pole of one molecule attracts the negative pole of another.
In water, the intermolecular bond is hydrogen bonds in which an electrostatic attraction exists between the hydrogen atom of one molecule and the electronegative atom of a neighbouring molecule.
Based on their relative strength:
Van der Waals forces < Hydrogen bonding forces < crystal lattice
This makes water boil at a higher temperature than hydrogen sulfide.
Answer:
Bird eating worm: The bird gains energy from eating its proteins.
Plant recieving sunlight: The plant gains energy from the sunlight and transfers it into sugar and energy for it to continue its cycle.
Light bulb attached to battery: The lightbulb gains electricity and power from the battery until it runs out completely.
Step 1:
Divide mass of each element with its M.mass in order to find out moles.
C = 63.2 g / 12 g/mol = Moles = 5.26 moles
H = 5.26 g / 1.008 g/mol = Moles = 5.21 moles
C = 41.6 g / 16 g/mol = Moles = 2.6 moles
Step 2:
Select moles of the element with least value and divide all moles of element by it,
C H O
5.26/2.6 : 5.21/2.6 : 2.6/2.6
2.02 : 2.00 : 1
Result:
Empirical Formula = C₂H₂O
Answer:
–187.9 J/K
Explanation:
The equation that relates the three quantities is:
where
is the Gibbs free energy
is the change in enthalpy of the reaction
T is the absolute temperature
is the change in entropy
In this reaction we have:
ΔS = –187.9 J/K
ΔH = –198.4 kJ = -198,400 J
T = 297.0 K
So the Gibbs free energy is
However, here we are asked to say what is the entropy of the reaction, which is therefore
ΔS = –187.9 J/K
