Answer:
a. endothermic reaction
Explanation:
In an endothermic reaction, heat is absorbed from the environment. This leaves the surrounding at a colder temperature compared to the system.
ΔH, the change in enthalpy is assigned a positive sign because the heat energy level of the final state is higher than that of the initial state.
Some examples are mostly dissolution substances in water.
The outermost electrons of the atom are either lost or gained by one of the atoms to the other. therefore the atom gains negative charge when gaining and positive charge when losing
Explanation:
Average atomic mass of the vanadium = 50.9415 amu
Isotope (I) of vanadium' s abundance = 99.75 %= 0.9975
Atomic mass of Isotope (I) of vanadium ,m= 50.9440 amu
Isotope (II) of vanadium' s abundance =(100%- 99.75 %) = 0.25 % = 0.0025
Atomic mass of Isotope (II) of vanadium ,m' = ?
Average atomic mass of vanadium =
m × abundance of isotope(I) + m' × abundance of isotope (II)
50.9415 amu =50.9440 amu× 0.9975 + m' × 0.0025
m'= 49.944 amu
The atomic mass of isotope (II) of vanadium is 49.944 amu.