Fox News – Breaking News Updates

latest news and breaking news today source : periodic-table.org

## Neutron Number and Mass Number of Chlorine

Mass numbers of typical isotopes of Chlorine are 35; 37.

The total number of neutrons in the nucleus of an atom is called the neutron number of the atom and is given the symbol N. Neutron number plus atomic number equals atomic mass number: N+Z=A. The difference between the neutron number and the atomic number is known as the neutron excess: D = N – Z = A – 2Z.

Neutron number is rarely written explicitly in nuclide symbol notation, but appears as a subscript to the right of the element symbol. Nuclides that have the same neutron number but a different proton number are called isotones. The various species of atoms whose nuclei contain particular numbers of protons and neutrons are called nuclides. Each nuclide is denoted by chemical symbol of the element (this specifies Z) with tha atomic mass number as supescript. Therefore, we cannot determine the neutron number of uranium, for example. We can determine the neutron number of certain isotope. For example, the neutron number of uranium-238 is 238-92=146.

Neutron and Mass Numbers and Nuclear Properties

Properties of atomic nuclei (atomic mass, nuclear cross-sections) are determined by the number of protons and number of neutrons (neutron number). It must be noted, especially nuclear cross-sections may vary by many orders from nuclide with the neutron number N to nuclide with the neutron number N+1. For example, actinides with odd neutron number are usually fissile (fissionable with slow neutrons) while actinides with even neutron number are usually not fissile (but are fissionable with fast neutrons). Heavy nuclei with an even number of protons and an even number of neutrons are (due to Pauli exclusion principle) very stable thanks to the occurrence of ‘paired spin’. On the other hand, nuclei with an odd number of protons and neutrons are mostly unstable.

Neutron and Atomic Numbers and Nuclear Stability

Nuclear stability is a concept that helps to identify the stability of an isotope. To identify the stability of an isotope it is needed to find the ratio of neutrons to protons. To determine the stability of an isotope you can use the ratio neutron/proton (N/Z). Also to help understand this concept there is a chart of the nuclides, known as a Segre chart. This chart shows a plot of the known nuclides as a function of their atomic and neutron numbers. It can be observed from the chart that there are more neutrons than protons in nuclides with Z greater than about 20 (Calcium). These extra neutrons are necessary for stability of the heavier nuclei. The excess neutrons act somewhat like nuclear glue. Only two stable nuclides have fewer neutrons than protons: hydrogen-1 and helium-3.

Atomic nuclei consist of protons and neutrons, which attract each other through the nuclear force, while protons repel each other via the electric force due to their positive charge. These two forces compete, leading to various stability of nuclei. There are only certain combinations of neutrons and protons, which forms stable nuclei.

Neutrons stabilize the nucleus, because they attract each other and protons , which helps offset the electrical repulsion between protons. As a result, as the number of protons increases, an increasing ratio of neutrons to protons is needed to form a stable nucleus. If there are too many or too few neutrons for a given number of protons, the resulting nucleus is not stable and it undergoes radioactive decay. Unstable isotopes decay through various radioactive decay pathways, most commonly alpha decay, beta decay, gamma decay or electron capture. Many other rare types of decay, such as spontaneous fission or neutron emission are known.

## Atomic Mass of Chlorine

Atomic mass of Chlorine is 35.453 u.

The atomic mass is the mass of an atom. 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. The atomic mass is carried by the atomic nucleus, which occupies only about 10-12 of the total volume of the atom or less, but it contains all the positive charge and at least 99.95% of the total mass of the atom. Note that, each element may contain more isotopes, therefore this resulting atomic mass is calculated from naturally-occuring isotopes and their abundance.

The size and mass of atoms are so small that the use of normal measuring units, while possible, is often inconvenient. Units of measure have been defined for mass and energy on the atomic scale to make measurements more convenient to express. The unit of measure for mass is the atomic mass unit (amu). One atomic mass unit is equal to 1.66 x 10-24 grams. One unified atomic mass unit is approximately the mass of one nucleon (either a single proton or neutron) and is numerically equivalent to 1 g/mol.

For 12C the atomic mass is exactly 12u, since the atomic mass unit is defined from it. For other isotopes, the isotopic mass usually differs and is usually within 0.1 u of the mass number. 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.

There are two reasons for the difference between mass number and isotopic mass, known as the mass defect:

The neutron is slightly heavier than the proton. This increases the mass of nuclei with more neutrons than protons relative to the atomic mass unit scale based on 12C with equal numbers of protons and neutrons.The nuclear binding energy varies between nuclei. A nucleus with greater binding energy has a lower total energy, and therefore a lower mass according to Einstein’s mass-energy equivalence relation E = mc2. For 63Cu the atomic mass is less than 63 so this must be the dominant factor.

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. Mass was no longer considered unchangeable in the closed system. The difference is a measure of the nuclear binding energy which holds the nucleus together. According to the Einstein relationship (E=mc2), this binding energy is proportional to this mass difference and it is known as the mass defect.

See also: Atomic Mass Number – Does it conserve in a nuclear reaction?

Hydrogen

Nonmetals

Helium

Noble gas

Lithium

Alkali metal

Beryllium

Alkaline earth metal

Boron

Metalloids

Carbon

Nonmetals

Nitrogen

Nonmetals

Oxygen

Nonmetals

Fluorine

Nonmetals

Neon

Noble gas

Sodium

Alkali metal

Magnesium

Alkaline earth metal

Aluminium

Post-transition metals

Silicon

Metalloids

Phosphorus

Nonmetal

Sulfur

Nonmetal

Chlorine

Nonmetal

Argon

Noble gas

Potassium

Alkali metal

Calcium

Alkaline earth metal

Scandium

Transition metals

Titanium

Transition metals

Transition metals

Chromium

Transition metals

Manganese

Transition metals

Iron

Transition metals

Cobalt

Transition metals

Nickel

Transition metals

Copper

Transition metals

Zinc

Transition metals

Gallium

Post-transition metals

Germanium

Metalloids

Arsenic

Metalloids

Selenium

Nonmetal

Bromine

Nonmetal

Krypton

Noble gas

Rubidium

Alkali metals

Strontium

Alkaline earth metals

Yttrium

Transition metals

Zirconium

Transition metals

Niobium

Transition metals

Molybdenum

Transition metals

Technetium

Transition metals

Ruthenium

Transition metals

Rhodium

Transition metals

Transition metals

Silver

Transition metals

Transition metals

Indium

Post-transition metals

Tin

Post-transition metals

Antimony

Metalloids

Tellurium

Metalloids

Iodine

Nonmetal

Xenon

Noble gas

Caesium

Alkali metals

Barium

Alkaline earth metals

Lanthanoids

Hafnium

Transition metals

Tantalum

Transition metals

Tungsten

Transition metals

Rhenium

Transition metals

Osmium

Transition metals

Iridium

Transition metals

Platinum

Transition metals

Gold

Transition metals

Mercury

Transition metals

Thallium

Post-transition metals

Post-transition metals

Bismuth

Post-transition metals

Polonium

Post-transition metals

Astatine

Metalloids

Noble gas

Francium

Alkali metal

Alkaline earth metal

Actinoids

Rutherfordium

Transition metal

Dubnium

Transition metal

Seaborgium

Transition metal

Bohrium

Transition metal

Hassium

Transition metal

Meitnerium

Roentgenium

Copernicium

Nihonium

Flerovium

Moscovium

Livermorium

Tennessine

Oganesson

Lanthanum

Lanthanoids

Cerium

Lanthanoids

Praseodymium

Lanthanoids

Neodymium

Lanthanoids

Promethium

Lanthanoids

Samarium

Lanthanoids

Europium

Lanthanoids

Lanthanoids

Terbium

Lanthanoids

Dysprosium

Lanthanoids

Holmium

Lanthanoids

Erbium

Lanthanoids

Thulium

Lanthanoids

Ytterbium

Lanthanoids

Lutetium

Lanthanoids

Actinium

Actinoids

Thorium

Actinoids

Protactinium

Actinoids

Uranium

Actinoids

Neptunium

Actinoids

Plutonium

Actinoids

Americium

Actinoids

Curium

Actinoids

Berkelium

Actinoids

Californium

Actinoids

Einsteinium

Actinoids

Fermium

Actinoids

Mendelevium

Actinoids

Nobelium

Actinoids

Lawrencium

Actinoids

Related Posts How many protons and neutrons are in each isotope of chlorine? – For chlorine-37 there are 20 neutrons and 17 protons. Also remember that the # of protons do not change, only the neutron to form an isotope. Lucas C. Lv 7. 1 decade ago. All isotopes of chlorine have 17 protons (that's what makes them chlorine atoms). The mass number is the sum of protons and neutrons, so for Cl-35, there are 35-17 = 18 neutrons.The answer is 17 protons and 20 neutrons. The number 37 in chlorine indicates the mass number. A chlorine atom has a specific number of protons, which is 17 protons. Since the mass number is equal…A sample of chlorine has two naturally occurring isotopes. The isotope Cl-35 (mass 35.0 amu) makes up 75.8% of the sample, and the isotope Cl-37 (mass = 37.0 amu) makes up the 24.3% of the sample. What is the average atomic mass for chlorine?:

An atom of chlorine-37 has: – 37 neutrons and 17 protons – Isotopes are atoms with the same number of protons (in the case of chlorine that means 17 protons) but different numbers of neutrons. Chlorine has two common isotopes, Chlorine-35 and Chlorine-37. The atomic mass, or as it is properly called, the RELATIVE atomic mass, is a weighted average of the masses of all the isotopes of chlorine.Do most chlorine atoms contain 18 neutrons or 20 neutrons? Not all atoms of an element, therefore, have the same atomic mass number. All chlorine atoms, for instance, have 17 protons. However, some chlorine atoms have 18 neutrons, while other chlorine atoms have 20 neutrons. Atoms of chlorine with 18 and 20 neutrons are called chlorine isotopes.Which statement is correct about chlorine-35 and chorine-37? They have the same number of protons and electrons, but a different number of neutrons. The fact that LiBr is 7.99 % lithium and 92.01 % bromine by mass regardless of its origin is an example of _____. law of definite proportions. CHEM Chapter 4: Atoms Flashcards | Quizlet – Chlorine-37 (37 Cl), is one of the stable isotopes of chlorine, the other being chlorine-35 (35 Cl). Its nucleus contains 17 protons and 20 neutrons for a total of 37 nucleons.Chlorine-37 accounts for 24.23% of natural chlorine, chlorine-35 accounting for 75.77%, giving chlorine atoms in bulk an apparent atomic weight of 35.453(2) g/mol.Chlorine. It was discovered in 1774 but it wasn't until 1810 that Sir Humphry Davy determined it to be an element. It is not a found freely in nature but is derived from salt. It is a toxic gas which will irritate the respiratory system. In World War I, it was used as an agent to kill.How many protons, neutrons, and electrons are in chlorine 37? Step 1: For the number of protons, it is equal to the atomic number. You can look up the atomic number for any element… Step 2: For the number of neutrons, you need the Atomic Mass. The Atomic Mass is (roughly)           