Astronomy 10 Chapter 11 1. Both used to be normal stars but the white dwarf ran out of hydrogen, they are both subjected to gravitational theories. A Neutron star is a fluid of neutrons, as hot at its surface as the inside of the sun and has a greater magnetic field. 3. Because its density is so high, neutrons spin in the same way that electrons do so must obey the Pauli Exclusion Principle.
Non-metals cannot conduct electricity or heat very well. As opposed to metals, non-metal elements are very brittle, and cannot be rolled into wires. The non-metals exist in two of the three states of matter at room temperature gases and solids. Alkali Metals are made up of six different elements and are found in group one on the periodic table. These metals have only one electron in their outer shell.
Column 17 is made up of the more reactive gases- the halogens. The noble gases are in column 18. The electrons are the most significant part of an atom. When atoms don’t have the sufficient number of electrons they need in their outer level, they will do whatever they can to get the number they need. The number of protons an atom has is its atomic number.
HSC Chemistry Assessment task 1 Nuclear Chemistry Research report 1. Distinguish between stable and radioactive isotopes and describe the conditions which a nucleus is unstable. To understand if an element is stable we first must understand what stability is. The stability of the nucleus is directly related to the strength of the forces that hold the nuclear particles together. These protons and neutrons of the nucleus are called nucleons.
Your friend says that what makes one element distinct from another is the number of electrons about the atomic nucleus. Do you agree wholeheartedly, partially, or not at all? Explained • NO • What makes one element distinct from another is the number of protons in the nucleus. Hydrogen has 1, gold has 79, uranium has 92, etc. Not electrons.
Atoms and Ions Atoms have no net charge. They are neutral. Ions have a charge, either positive or negative. A positive ion has more protons than electrons. CATION A negative ion has more electrons than protons.
A molecular orbital is merely a Schrödinger orbital which includes several, but often only two nuclei. If this orbital is of type in which the electron(s) in the orbital have a higher probability of being between nuclei than elsewhere, the orbital will be a bonding orbital, and will tend to hold the nuclei together. If the electrons tend to be present in a molecular orbital in which they spend more time elsewhere than between the nuclei, the orbital will function as an anti-bonding orbital and will actually weaken the bond. Electrons in non-bonding orbitals tend to be in deep orbitals (nearly atomic orbitals) associated almost entirely with one nucleus or the other, and thus they spend equal time between nuclei or not. These electrons neither contribute nor detract from bond strength.
Which of the following is a trace element that is required by humans and other vertebrates? A) nitrogen B) calcium C) iodine D) sodium E) phosphorus 3) Each element is unique and different from other elements because of the number of protons in the nuclei of its atoms. Which of the following indicates the number of protons in an atom's nucleus? A) atomic mass B) atomic weight C) atomic number D) mass weight E) mass number 4) Calcium has an atomic number of 20 and an atomic mass of 40. Therefore, a calcium atom must
It is so small that it cannot be viewed under a microscope. An atom can be thought of as a ball and inside that ball there are two major parts. In the center of the atom there is the Nucleus this is the tiny, dense and positively charged center of an atom which contains protons and neutrons. A Proton is a subatomic particle that has the smallest
OCR B CHEMISTRY F331 (Unit 1) Revision Guide 2014 Formulae, equations and amount of substance | Key Terms (a). * Atomic Number: Atomic number is the number of protons in the nucleus. * Mass Number: Mass number is defined as the sum of the numbers of protons and neutrons in the atom’s nucleus. * Isotopes: Atoms with the same number of protons but different number of neutrons are called isotopes; they therefore have different masses. * Avogadro’s constant: The number of toms per mole is called the Avogadro’s constant.