But this “huge” space is occupied primarily by electrons, because the nucleus occupies only about 1721×10−45 m3 of space. All of the alkali metals have a single valence electron in the outer electron shell, which is easily removed to create an ion with a positive charge – a cation, which combines with anions to form salts. Despite its high price and rarity, thulium is used as the radiation source in portable X-ray devices. Arsenic occurs in many minerals, usually in combination with sulfur and metals, but also as a pure elemental crystal. The Cookies Statement is part of our Privacy Policy. Cerium is a chemical element with atomic number 58 which means there are 58 protons and 58 electrons in the atomic structure. The chemical symbol for Caesium is Cs. Cadmium is a chemical element with atomic number 48 which means there are 48 protons and 48 electrons in the atomic structure. Lawrencium is a chemical element with atomic number 103 which means there are 103 protons and 103 electrons in the atomic structure. The difference between the neutron number and the atomic number is known as the neutron excess: D = N – Z = A – 2Z.

Density is defined as the mass per unit volume. Rising temperatures make the liquid expand in a liquid-in-tube thermometer and bend bimetallic strips.

It readily forms hard, stable carbides in alloys, and for this reason most of world production of the element (about 80%) is used in steel alloys, including high-strength alloys and superalloys. The chemical symbol for Thorium is Th.

1) You may use almost everything for non-commercial and educational use. The reason is that the molar mass of the substance affects the conversion. Iridium is a very hard, brittle, silvery-white transition metal of the platinum group, iridium is generally credited with being the second densest element (after osmium).

It may seem, that the space and in fact the matter is empty, but it is not.

For example, 63Cu (29 protons and 34 neutrons) has a mass number of 63 and an isotopic mass in its nuclear ground state is 62.91367 u.

The chemical symbol for Potassium is K. Potassium was first isolated from potash, the ashes of plants, from which its name derives. Given mass of Al(NO3)3 = 12.0 g 

It is a noble metal and a member of the platinum group. Calculate the atomic mass of magnesium. Bromine is the third-lightest halogen, and is a fuming red-brown liquid at room temperature that evaporates readily to form a similarly coloured gas. The chemical symbol for Oxygen is O.

For 12C the atomic mass is exactly 12u, since the atomic mass unit is defined from it. The chemical symbol for Germanium is Ge. Hydrogen is a chemical element with atomic number 1 which means there are 1 protons and 1 electrons in the atomic structure. For other isotopes, the isotopic mass usually differs and is usually within 0.1 u of the mass number.

Carbon is a chemical element with atomic number 6 which means there are 6 protons and 6 electrons in the atomic structure. The chemical symbol for Palladium is Pd. Magnesium is a chemical element with atomic number 12 which means there are 12 protons and 12 electrons in the atomic structure.

Due to the quantum nature of electrons, the electrons are not point particles, they are smeared out over the whole atom. The theo... Q: What mass of oxygen is needed for the complete combustion of 6.70×10−3 gg of methane? The atomic mass is the mass of an atom.

Boron is a chemical element with atomic number 5 which means there are 5 protons and 5 electrons in the atomic structure. The configuration of these electrons follows from the principles of quantum mechanics.

Hydrogen has a mass of 1, so 1 multiply by 2 is equal to 2. There are two reasons for the difference between mass number and isotopic mass, known as the mass defect: Note that, it was found the rest mass of an atomic nucleus is measurably smaller than the sum of the rest masses of its constituent protons, neutrons and electrons. The chemical symbol for Promethium is Pm. The chemical symbol for Mendelevium is Md. Silver is a soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal.

Aluminium is a silvery-white, soft, nonmagnetic, ductile metal in the boron group.

Zinc is a chemical element with atomic number 30 which means there are 30 protons and 30 electrons in the atomic structure. Discoverer: Davy, Sir H. and Thénard, L.-J. 24.305 + 32.065 + 15.9994*4 + 7*(1.00794*2 + 15.9994). The chemical symbol for Hafnium is Hf. The atomic mass or relative isotopic mass refers to the mass of a single particle, and therefore is tied to a certain specific isotope of an element.

Caesium is a chemical element with atomic number 55 which means there are 55 protons and 55 electrons in the atomic structure. As a result, the electron cloud contracts and the atomic radius decreases. Hafnium’s large neutron capture cross-section makes it a good material for neutron absorption in control rods in nuclear power plants, but at the same time requires that it be removed from the neutron-transparent corrosion-resistant zirconium alloys used in nuclear reactors. Atomic Mass of Magnesium.

Using the chemical formula of the compound and the periodic table of elements, we can add up the atomic weights and calculate molecular weight of the substance. Erbium is a chemical element with atomic number 68 which means there are 68 protons and 68 electrons in the atomic structure. Its extreme rarity in the Earth’s crust, comparable to that of platinum.