The list below includes some of the properties of butane, a common fuel. Identify the chemical properties in the list. Check all
1 answer:
You might be interested in
Answer: Option (b) is the correct answer.
Explanation:
The energy necessary to remove an electron from a gaseous atom or ion is known as ionization energy.
This means that smaller is the size of an atom more amount of energy has to be supplied to it in order to remove the valence electron. This is because in small atom or element there will be strong force of attraction between the nucleus and electrons.
So, high amount of energy has to be supplied to remove the valence electrons.
As electronic configuration of helium is . So, due to completely filled valence shell it is more stable in nature.
As a result, we need to provide very high amount of energy to remove an electron from a helium atom.
Thus, we can conclude that out of the given options helium element would the first ionization energy of the atom be higher than that of the diatomic molecule.
Answer : The combustion is a process in which oxygen is released as a by-product of oxidation-reduction reactions.
Explanation :
Combustion reaction : It is defined as the reactions in which a hydrocarbon reacts with oxygen gas to produce carbon dioxide and water.
The chemical equation of combustion reaction is:
The combustion reaction is also a redox reaction.
Redox reaction or Oxidation-reduction reaction : It is defined as the reaction in which the oxidation and reduction reaction takes place simultaneously.
Oxidation reaction : It is defined as the reaction in which a substance looses its electrons. In this, oxidation state of an element increases. Or we can say that in oxidation, the loss of electrons takes place.
Reduction reaction : It is defined as the reaction in which a substance gains electrons. In this, oxidation state of an element decreases. Or we can say that in reduction, the gain of electrons takes place.
The combustion reaction is also a redox reaction in which the carbon shows oxidation by the addition of oxygen or removal of hydrogen and oxygen shows reduction by the addition of hydrogen or removal of oxygen.
Hence, the combustion is a process in which oxygen is released as a by-product of oxidation-reduction reactions.
Answer:
i) 0.5071 (kg/s)
ii) -1407.1 kj/kg
iii) 204.05 Kw
iv) 5.881
v) 9.238
Explanation:
Given Data:
evaporation temperature ( T ) = 4°c = 277.15 K
Condensation Temperature ( T ) = 34°c = 307.15 K
<em>n</em> ( compressor efficiency ) = 0.76
refrigeration rate = 1200 kJ.s^-1
i) determine the circulation rate of the refrigerant
m = =
------- 1
Q = 1200 Kj.s^-1
H2 = entropy at step 2 = 2508.9 (kJ / kg ) ( gotten from Table F )
H4 = entropy at step 4 = 142.4 ( kJ/ kg )
back to equation 1
m ( circulation rate of refrigerant ) = 0.5071 (kg/s)
ii) heat transfer rate in the condenser
Q = m ( H4 - H3 )
= 0.5071 ( 142.4 - 2911.27 )
= -1407.1 kj/kg
where H3 = H2 + ΔH23 = 2911.27 (kj/kg) ( as calculated )
iii) power requirement
w = m * ΔH23
= 0.5071 (kg/s) * 402.37 (kj/kg) = 204.05 Kw
where: ΔH23 = =
= 402.37 (kj/kg)
iv) coefficient of performance of a cycle
W = Qc / w
= 1200 Kj.s^-1/ 204.05 kw
= 5.881
v) coefficient of performance of a Carnot refrigeration cycle
= 277.15 / ( 307.15 - 277.15 )
= 9.238