Answer:
Hey
It would have to be C because no net energy is lost.
Answer: D. The elements have the same number of valence electrons
Explanation: The chemical reactivity of elements is governed by the valence electrons present in the element.
The elements present in the same group or vertical column have similar valence configurations and thus behave similarly in chemical reactions or have similar bonding properties.
For Example: Both fluorine and chlorine belong to same family or group and both have 7 electrons in their valence shell and thus accept single electron to attain noble gas configuration.




thus both would bond with a cation bearing a single positive charge.
<span>Recall formula for Kinetic energy is:
KE = 1/2mv^2, where KE = 275J
and momentum (which is 25.0 kg m/s) = m*v
Therefore substitute for KE and mv in the equation above to get speed
=> 275 = 0.5 * 25 * v
v = 275/12.5
v = 22m/s
to get mass m, recall momentum = m*v
=> 25= 22*m
m= 25/22 = 1.3663kg</span>