Answer:
because only two electrons can fit in the first orbit around the nucleus, and each period on the table is organized by number of orbits
If a particle undergoes simple harmonic motion with an amplitude of 0.21 meters, this means that the maximum displacement of the particle from its resting position is 0.21. For one period, it traveled from its starting position which is twice the amplitude and then back to its original position which is another distance that is twice the amplitude as well. Therefore, the total distance it traveled is 2*amplitude + 2*amplitude = 2*0.21 + 2*0.21 = 0.42 + 0.42 = 0.84 meters.
As the <em>voltage</em> applied to a crcuit increases, the power dissipated by the circuit, and the current flowing through the circuit, both also increase.
Answer: -4.4 m/s
Explanation:
This problem can be solved by the Conservation of Momentum principle, which establishes that the initial momentum 
must be equal to the final momentum 
:
(1)
Where:
(2)
(3)
is the mass of the child
is the initial velocity of the child
is the mass of the adult
is the initial velocity of the adult (it is sitting still)
is the final velocity of the child
is the final velocity of the adult
Substituting (2) and (3) in (1):
(4)
Isolating :
(5)
(6)
Finally:
This means the velocity of the child is in the opposite direction
Sodium sulfide formula is Na₂S.
Na is a group 1 element, it has one valence electron therefore it is ready to give that valence electron and form an ionic bond. Once it gives out the electron it becomes a positive ion - Na⁺
sulfur is a group 6 element, has 6 electrons its outer shell and needs to gain 2 more electrons to become stable. Once it gains 2 electrons it becomes a negative ion - S²⁻.
Since Na only gives out 1 electron, S²⁻ ion needs to take in 2 electrons, therefore forms an ionic compound with 2 Na⁺ ions.
decomposition of Na₂S is as follows;
Na₂S(s) --> 2Na⁺(aq) + S²⁻ (aq)
