Answer:
The main group number for an element can be found from its column on the periodic table.
Explanation:
For example, carbon is in group 4 and has 4 valence electrons. Oxygen is in group 6 and has 6 valence electrons.
Silver is the densest as it is lower on the periodic table containing more protons and nuetrons and electrons
Answer: The frequency of the green light emitted by a hydrogen atom with a wavelength of 546 nm is 
.
Explanation:
Given: Wavelength = 546 nm 
= 
The relation between frequency and wavelength is as follows.
where,
= frequency
c = speed of light = 
= wavelength
Substitute the values into above formula as follows.
Thus, we can conclude that the frequency of the green light emitted by a hydrogen atom with a wavelength of 546 nm is .
Answer:
The amount of kinetic energy an object has depends on its
Motion
Explanation:
Only kinetic energy increases when the velocity of an object increases.
Rechargeable batteries use a reversible reaction medium to convert electrical current to a form of chemical energy which can be stored for future use.
<h3>
What is a rechargeable battery?</h3>
A rechargeable battery is a type of battery that can be charged many times by passing electric current through the cells in a reversible reaction.
<h3>How does recahargeable battery store energy?</h3>
When electrical energy from an outside source is applied to a secondary cell (reachargeable battery), the negative to positive electron flow that occurs during discharge is reversed, and the cell's charge is restored. This process is called reversible reaction.
Thus, rechargeable batteries use a reversible reaction medium to convert electrical current to a form of chemical energy which can be stored for future use.
Learn more about reversible reaction here: brainly.com/question/11412193
