Answer:
₂He⁴
Explanation:
Alpha radiations are emitted as a result of radioactive decay. The atom emit the alpha particles consist of two proton and two neutrons. Which is also called helium nuclei. When atom undergoes the alpha emission the original atom convert into the atom having mass number less than 4 and atomic number less than 2 as compared to parent atom the starting atom.
Properties of alpha radiation:
Alpha radiations can travel in a short distance.
These radiations can not penetrate into the skin or clothes.
These radiations can be harmful for the human if these are inhaled.
These radiations can be stopped by a piece of paper.
₉₂U²³⁸ → ₉₀Th²³⁴ + ₂He⁴ + energy
H2(g) +C2H4(g)→C2H6(g)
H-H +H2C =CH2→H3C-Ch3
2C -H bonds and one C-C bond are formed while enthalpy change (dH) of the reaction,
H-H: 432kJ/mol
C=C: 614kJ/mol
C-C: 413 kJ/mol
C-C: 347 kJ/mol
dH is equal to sum of the energies released during the formation of new bonds or negative sign, and sum of energies required to break old bonds or positive sign.
The bond which breaks energy is positive.
432+614 =1046kJ/mol
Formation of bond energy is negative
2(413) + 347 = 1173 kJ/mol
dH reaction is -1173 + 1046 =-127kJ/mol
Substance a is a base, and substance b is an acid
Answer: 83.11 torr
Explanation:
According to Dalton's Law of partial pressure, the total pressure of a mixture of gases is the sum of the pressure of each individual gas.
i.e Ptotal = P1 + P2 + P3 + .......
In this case,
Ptotal = 384 torr
P1 = 289 torr
P2 = 11.89 torr
P3 = ? (let the partial pressure of the remaining gas be Z)
Ptotal = P1 + P2 + Z
384 torr = 289 torr + 11.89 torr + Z
384 torr = 300.89 torr + Z
Z = 384 torr - 300.89 torr
Z = 83.11 torr
Thus, the partial pressure of the remaining gas is 83.11 torr.