Subatomic Particles and the periodic table 1. The three particles and their properties An atom has no overall charge. The protons (positively charged) and neutrons (no charge) make up the nucleus of an atom, and this is surrounded by negatively charged electrons. There are as many protons as electrons, so they balance each other out, creating a neutral relative charge on the atom. Neutrons, Protons and electrons are all sub-atomic particles.
An ionic bond is the transfer of valence electrons between atoms. It is a type of chemical bond that creates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, the non-metal accepts those electrons to become a negatively charged anion. Ionic bonds require an electron donor, metal, and an electron acceptor, nonmetal. By losing those electrons, these metals can achieve noble-gas configuration and satisfy the octet rule.
Electromagnetism Everything is made out of atoms. Atoms consist of a nucleus (containing neutrons and protons) and a cloud of electrons surrounding the nucleus. Protons are positively charged and electrons are negatively charged. If an object has more protons than neutrons, then it is negatively charged. If an object has more electrons than protons, then it is positively charged.
A molecule in which the central atom forms three single bonds and has one lone pair is said to have a ________ shape. A) bent B) linear C) planar D) pyramidal E) tetrahedral 8. A bond where the electrons are shared equally is called a(an) ________ bond. A) polar covalent B) coordinate covalent C) nonpolar covalent D) ionic E) none of the above 9. In a precipitation reaction the insoluble product can be identified by the symbol ________.
The electrons of an atom are bound to the nucleus by the electromagnetic force. A group of atoms can remain bound to each other by chemical bonds based on the same force, forming a molecule. An atom containing an equal number of protons and electrons is neutral; otherwise it is positively or negatively charged and is known as an ion. An atom is classified according to the number of protons and neutrons in its nucleus the number of protons controls the element, and the number of neutrons determines the isotope of the element. A molecule is an electrically neutral group of two or more atoms held together by chemical bonds Molecules are recognized from ions by their lack of
K+Cl --> KCl 2) Subscripts You can never change subscripts in a chemical equation. This equation is a bit harder, but you can see how to get more atoms when you need them. H2O+Fe ---> Fe2O3+H2 The first thing you need to do to solve this equation is to count the number of each type of atom on both sides. There are two hydrogen atoms on the left, and two on the right. Balanced.
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.
INTRODUCTION TO NUCLEAR REACTION: The main features of nuclear reactions include radioactive decay, nuclear fission and nuclear fusion. Radioactive decay: Energy is released in a radioactive decay in the form of the kinetic energy of the particle emitted (α and β), the kinetic energy of the daughter nucleus and the energy of the gamma-ray photon that may accompany the decay. The energy involved may be calculated by finding the mass defect of the reaction. The energy released is the energy equivalent of the mass defect of the reaction. Nuclear fission: Nuclear fission is the process in which a large nucleus breaks into two smaller nuclei that are almost equal in mass.
David Kemp OCR Chemistry A Unit 1: F321 Atomic Structure (a) describe protons, neutrons and electrons in terms of relative charge and relative mass; Proton +1 1 Neutron 0 1 Electron -1 1/2000 Relative Charge Relative Mass (b) describe the distribution of mass and charge Within an atom; Positively charged Nucleus containing most of the mass, surrounded by atomic shells with orbiting electrons of negative charge and negligible mass. (c) describe the contribution of protons and neutrons to the nucleus of an atom, in terms of atomic (proton) number and mass (nucleon) number. The atomic number of the nucleus, also the proton number, shows the number of protons in the nucleus. It also defines the element. The number of neutrons added to the number of protons is the nucleon number or mass number.