Answer:
Group 1
Explanation: because the compound has a formula of M2O , the number of valence electrons of M should be 1.
Drill cores from the ocean floor were dated and found to be very young compared to the age of the earth. This means the crust had to be formed recently, which can be explained by creation of crust at a spreading center.
Explanation:
1. subatomic particles.
2.proton, electron and neutron
3.The atomic mass of an element is actually the sum of the MASSES of protons and neutrons in AN atom of that element
4.An element's atomic number is equal to the number of protons in the nuclei of any of its atoms
5. Number of Protons = Atomic Number
Number of Electrons = Number of Protons = Atomic Number
Number of Neutrons = Mass Number - Atomic Number
For krypton:
Number of Protons = Atomic Number = 36
Number of Electrons = Number of Protons = Atomic Number = 36
Number of Neutrons = Mass Number - Atomic Number = 84 - 36 = 48
6. electron, lightest stable subatomic particle known. It carries a negative charge of 1.602176634 × 10−19 coulomb, which is considered the basic unit of electric charge. The rest mass of the electron is 9.1093837015 × 10−31 kg
7.The center of the atom is called a nucleus
8. Negatively charged particles are found in multiple layers outside the nucleus of the atom. These particles are called electrons, and they orbit in various energy levels around the atom's nucleus.
9. A charged particle is also called an ion
As the air molecules move through the valve they have friction as they hit the walls, and its this friction that causes it to heat up.
An element is a pure substance made up of only one kind of atom. An element is composed of atoms in which it is composed of neutrons and protons. The nucleus is surrounded by electrons. The answer to this problem is A. element
