The mass of an electron can be expressed in the box as 
.
Further explanation:
Atom is the smallest particle that can be present in any element. It is also known as the building unit of matter. Each atom has a central part that is known as the atomic nucleus. There are three subatomic particles that constitute the atom. These particles are protons, neutrons, and electrons. The atomic nucleus consists of protons and neutrons, both are collectively called nucleons. Electrons revolve around the nucleus of an atom in definite orbits.
Protons are positively charged subatomic particles, electrons are negatively charged and neutrons have no charge. Since electrons carry a unit negative charge, these create an electric field around them. These also participate in nuclear reactions. The mass of an electron 
is 
, that of protons is 
and that of neutrons is 
. The electrons are responsible for chemical properties of elements. The distribution and arrangement of electrons is used to predict whether the element will be inert or reactive.
Therefore the required answer is .
Learn more:
- Component of John Dalton’s atomic theory: brainly.com/question/2357175
- Basis of investigation for the scientists: brainly.com/question/158048
Answer details:
Grade: Senior School
Subject: Chemistry
Chapter: Atomic structure
Keywords: atom, matter, atomic nucleus, proton, electron, neutron, subatomic particle, nuclear reactions, electric field, reactive, inert.
They each have one valence electron in their outer shell, but they are also on the same row (period). If you follow this pattern, potassium will also have one valence electron.
Hope this helps!! :)
Answer:
Mass + Atomic number. Sorry if I'm wrong I haven't been studying chem lately
<u>Full question:</u>
When energy is changed from one form to another, some of the energy is lost to the surroundings as waste thermal energy. The more steps needed to arrive at the desired energy or the more types of energy that are generated, the more energy is wasted.
Which object would likely have the least amount of wasted energy?
A) an electric drill
B) a solar cell
C) a car engine
D) a hydroelectric dam
Solar cell
<u>Explanation:</u>
In an electric drill, the conversion of electrical energy into mechanical energy takes place. Heat energy is obtained when the desired object gets broken with the drill.
In car engine, thermal energy is obtained from the chemical energy which in turn is converted into mechanical energy which is very essential for moving car.
In hydroelectric dam, energy is obtained from water that is stored in dam. The potential energy of water is transformed into mechanical energy which in turn is converted into kinetic energy which again is transformed into an electrical energy.
In the above methods the transformation of energy takes many steps wherein more amount of energy gets wasted.
In Solar cell, the energy that is obtained from the sun is directly converted into electrical energy. Hence, in solar cell, only less amount of energy will be wasted.
