D.
Energy cannot be created nor destroyed. It is just transferred through sound, heat and light.
Answer:
The correct answer is - alpha particle and positron.
Explanation:
In this question, it is given that, 38^88Sr decays to 34^84Kr, which means there is an atomic number decrease by 4, 38 to 34, and atomic mass decreases by 4 as well 88 to 84.
A decrease in the atomic mass is possible only when there is an emission of the alpha particle as an alpha particle is made of 2 protons and 2 neutrons. If an atom emits an alpha particle, there is a change in atomic number as it decreases by two, and its mass number decreases by four.
So after the emission of an alpha particle, the new atom would be
38^88Sr=> 36^84X => 34^84Kr
so there is also two positron emission that leads to decrease in atomic number by one with each emission:
38^88Sr=> 2^4He+ 36^84X => 36^84X + 2(1^0β+) => 34^84Kr
Positron decay is the conversion of a proton into a neutron with the emission of a positron that causes the atomic number is decreased by one, which causes a change in the elemental identity of the daughter isotope.
Answer:
The outer shell
Explanation:
I am not completely sure what you are looking for but an atom's valence electrons are the outer shell in a Bohr model.
It's true that the substance is contain 75% carbon and 25% H
