Neutron

Elements are made of a single type of atom, which cannot be broken down into anything smaller. Inside an atom are the subatomic particles protons (positively charged) and neutrons (neutral), and outside are the electrons (negatively charged) that orbit the atom in an electron cloud. When two or more atoms of an element or elements bond together, they form a compound. Depending on the type of elements, there are different kinds of bonds that could form. Ionic bonds form between the atoms of at…

The atom is the smallest unit of matter. The name “atom” comes from the Greek word atomos, which means “uncuttable.” Atomic theory states that all matter is made up of these small particles, and that these atoms, and the matter made from them, cannot be created nor destroyed, merely reshaped and reformed. Modern chemistry unofficially began in the eighteenth century. French scientist Antoine Lavoisier discovered the law of the conservation of mass c. 1785. This law states that “The total mass…

occurring random exponential decay is the process of radioactive decay. Some isotopes of nature are considered radioactive due to a specific characteristic of their nucleus. Radioactive isotopes, or radioisotopes, do not contain the proper amount of neutrons. As a result of this, the nucleus of radioisotopes is unstable. The instability causes them to emit particles or electromagnetic waves from…

Just twenty years ago, physicists were starting to recognize that protons and neutrons are not elementary particles. Instead, they appeared to be composed of puzzling objects called “quarks.” A quark is now defined as an elementary particle that has an electrical charge equal to 1/3 or 2/3 that of an electron or proton (Riordan 608-609)…

electromagnetic energy called quanta. The electron cloud model and the quantum mechanics model are two different models talking about what the model looks like. They are both based on quantum mechanics. They both also involve a central location of protons and neutrons called the nucleus. But the quantum mechanics shows the electrons orbiting around the nucleus. The electron cloud shows the electrons more spread out like a cloud and they have no definite pattern they spread and move freely, like…

charged electrons. Here, the electrons represents the plume in the pudding of positive charge. Hence his model was known as plum pudding model. It was also known as watermelon model where the positive charge was the flesh of the watermelon and the electrons were the sects. a) J.J. Thomson who discovered the electron in 1897, proposed the plum pudding model of the atom in 1904 before the discovery of the atomic nucleus in order to include the electron in the atomic model. b) In Thomson’s model,…

Atomic mass: the mass of an atom of a chemical element expressed in atomic mass units; approximately equivalent to the number of protons and neutrons in the atom (the mass number) or to the average number allowing for the relative abundances of different isotopes Molar mass: a physical property defined as the mass of a given substance (chemical element or chemical compound) divided by the amount of substance Mole: the amount of a substance contained in 6.02 x 10²³ particles of that substance…

– equation (2 gives info on location of electron in terms of probability density - wave functions are called orbitals – [pic], where E is energy, e2 is electric potential, r is orbital radius and h is Planck’s constant 1925 Wolfgang Pauli – each orbital has only 2 electrons is now explained due to direction of spin of electrons. Spinning electrons create magnetic field. Only 2 electrons of opposite spin in an orbital referred to as Pauli exclusion principle Hund’s rule – half fill…

The Big Bang Theory is the current theory of the origin of the universe that has largely been accepted by scientists, however it is not one hundred percent correct as modifications of the theory is continuously being developed as new discoveries, observations and calculations are being made. In the beginning in the universe, there was nothing, no space, no matter, no light, no time and no sound. Then there was a sudden explosion of energy which we now call the Big Bang. But there was no BANG…

Assignment: Chemistry of Magnesium and Silicon Magnesium Properties Magnesium is a group is a group 2 element with the symbol, Mg, an atomic number of 12 and has a molar mass of 24.31 [1]. It is made up of 12 protons, 12 neutrons, and 12 electrons. It’s electron configuration is 1s2,2s2,2p6,3s2 this given as noble gas configuration is [Ne]3s2. It has a melting point of 650 °C and a boiling point of 1090 °C [2]. It has a metallic radius of 150 pm, a coordination number of 72(6), and a density of…