Answer:
Hydrogen: -141 kJ/g
Methane: -55kJ/g
The energy released per gram of hydrogen in its combustion is higher than the energy released per gram of methane in its combustion.
Explanation:
According to the law of conservation of the energy, the sum of the heat released by the combustion and the heat absorbed by the bomb calorimeter is zero.
Qc + Qb = 0
Qc = -Qb [1]
We can calculate the heat absorbed by the bomb calorimeter using the following expression.
Q = C . ΔT
where,
C is the heat capacity
ΔT is the change in the temperature
<h3>Hydrogen</h3>
Qc = -Qb = -C . ΔT = -(11.3 kJ/°C) . (14.3°C) = -162 kJ
The heat released per gram of hydrogen is:

<h3>Methane</h3>
Qc = -Qb = -C . ΔT = -(11.3 kJ/°C) . (7.3°C) = -82 kJ
The heat released per gram of methane is:

Answer:3Li+YbCl3=Yb +3LiCl
Explanation:as there are three cl in the first one so to balance them we will put 3before LiCl in order to make Cl balanced now there are 3 Li also so put before Li 3 making it also balanced Yb is balanced already
The given question is incomplete. The complete question is as follows.
Which of the following best helps explain why an increase in temperature increases the rate of a chemical reaction?
(a) at higher temperatures, high-energy collisions happen less frequently.
(b) at low temperatures, low-energy collisions happen more frequently.
(c) at higher temperatures, less-energy collisions happen less frequently.
(d) at higher temperatures, high-energy collisions happen more frequently
Explanation:
When we increase the temperature of a chemical reaction then molecules of the reactant species tend to gain kinetic energy. As a result, they come into motion which leads to more number of collisions within the molecules.
Therefore, chemical reaction will take less amount of time in order to reach its end point. This means that there will occur an increase in rate of reaction.
Thus, we can conclude that the statement at higher temperatures, high-energy collisions happen more frequently, best explains why an increase in temperature increases the rate of a chemical reaction.
To increase the energy of the emitted electrons, the frequency of the incident light on the metal must be increased.
<h3>What is energy of emitted electron?</h3>
The maximum energy of an emitted electron is equal to the energy of a photon for frequency f (E = hf ), minus the energy required to eject an electron from the metal's surface, also known as work function.
Ee = E - W
<h3>Energy of the emitted electron</h3>
The energy of emitted electrons based on the research of Albert Einstein is given as;
E = hf
where;
- h is planck's constant
- f is frequency of incident light on the metal
Thus, to increase the energy of the emitted electrons, the frequency of the incident light on the metal must be increased.
Learn more about energy of electron here: brainly.com/question/11316046
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