Explanation:
Calcium is the element that has 2 valence electrons.
Answer:
C. Lithium
Explanation:
This image describes the trend in reactivity. Group 1 metals are always the most reactive so yeah :)
Answer:
produce characteristic sets of energies, depending on the differences in energy between the excited states and ground state
Explanation:
The electron is jumped into higher level and back into lower level by absorbing and releasing the energy.
The process is called excitation and de-excitation.
Excitation:
When the energy is provided to the atom the electrons by absorbing the energy jump to the higher energy levels. This process is called excitation. The amount of energy absorbed by the electron is exactly equal to the energy difference of orbits. For example if electron jumped from K to L it must absorbed the energy which is equal the energy difference of these two level. The excited electron thus move back to lower energy level which is K by releasing the energy because electron can not stay longer in higher energy level and comes to ground state.
De-excitation:
When the excited electron fall back to the lower energy levels the energy is released in the form of radiations. this energy is exactly equal to the energy difference between the orbits. The characteristics bright colors are due to the these emitted radiations. These emitted radiations can be seen if they are fall in the visible region of spectrum
The most likely formula for an oxide formed between group 1a atom X and oxygen would be
X2O. - X is group 1a atom.
The number of beats the person have in 1.7 years is 6.7 x 10⁷ beats.
<h3>
Number of beats of the person</h3>
The number of beats of the person is calculated as follows;
n = bt
where;
- b is the beat rate
- n is number of beats
- t is time or duration
b = 75 beats/min
t = 1.7 years = 893520 mins
n = 75 beats/min x 893520 mins
n = 67,014,000
n = 6.7 x 10⁷ beats
Thus, the number of beats the person have in 1.7 years is 6.7 x 10⁷ beats.
Learn more about number of beats here: brainly.com/question/28245460
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