• Atomic Number 231
• Atomic Number 233

1. Atomic Number: 23 Atomic Mass: 50.9415 amu Melting Point: 1890.0 °C (2163.15 K, 3434.0 °F) Boiling Point: 3380.0 °C (3653.15 K, 6116.0 °F) Number of Protons/Electrons: 23 Number of Neutrons: 28 Classification: Transition Metal Crystal Structure: Cubic Density @ 293 K: 5.8 g/cm 3 Color: Silverish Atomic Structure.
2. Synonyms for atomic number 23 noun a soft silvery white toxic metallic element used in steel alloys Want to thank TFD for its existence? Tell a friend about us, add a link to this page, or visit the webmaster's page for free fun content.
3. The atomic mass of an element is the average mass of the atoms of an element measured in atomic mass unit (amu, also known as daltons, D).The atomic mass is a weighted average of all of the isotopes of that element, in which the mass of each isotope is multiplied by the abundance of that particular isotope.

The atomic mass of an element is the average mass of the atoms of an element measured in atomic mass unit (amu, also known as daltons, D). The atomic mass is a weighted average of all of the isotopes of that element, in which the mass of each isotope is multiplied by the abundance of that particular isotope. Vst plugin for mac. (Atomic mass is also referred to as atomic weight, but the term 'mass' is more accurate.)

For instance, it can be determined experimentally that neon consists of three isotopes: neon-20 (with 10 protons and 10 neutrons in its nucleus) with a mass of 19.992 amu and an abundance of 90.48%, neon-21 (with 10 protons and 11 neutrons) with a mass of 20.994 amu and an abundance of 0.27%, and neon-22 (with 10 protons and 12 neutrons) with a mass of 21.991 amu and an abundance of 9.25%. The average atomic mass of neon is thus:

A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.

Atomic Number 231

The atomic mass is useful in chemistry when it is paired with the mole concept: the atomic mass of an element, measured in amu, is the same as the mass in grams of one mole of an element. Thus, since the atomic mass of iron is 55.847 amu, one mole of iron atoms would weigh 55.847 grams. The same concept can be extended to ionic compounds and molecules. One formula unit of sodium chloride (NaCl) would weigh 58.44 amu (22.98977 amu for Na + 35.453 amu for Cl), so a mole of sodium chloride would weigh 58.44 grams. One molecule of water (H₂O) would weigh 18.02 amu (2×1.00797 amu for H + 15.9994 amu for O), and a mole of water molecules would weigh 18.02 grams.

The original periodic table of the elements published by Dimitri Mendeleev in 1869 arranged the elements that were known at the time in order of increasing atomic weight, since this was prior to the discovery of the nucleus and the interior structure of the atom. The modern periodic table is arranged in order of increasing atomic number instead.

If the atomic mass of an atom is #23*'amu'#, and there are 12 neutrons, how many protons are present?

1 Answer

If the atomic mass is #23#, and there are #12# neutrons, there MUST be #11# protons....

Explanation:

The mass of an atom depends on the number of nuclear particles: neutrons, massive particles with zero charge; and protons, massive particles with positive charge. Itunes 11 for mac os x.

The number of protons gives #Z,'the atomic number'#. And #Z# defines the identity of the element:

#Z=1, 'hydrogen'; Z=2, 'helium'; Z=3, 'lithium'; ...Z=6, 'carbon'......Z=92, 'uranium'# Desktop remote for mac os.

You don't have to be remember these numbers, because you should always have access to a Periodic Table (yes, even in exams). And thus you should be able to tell me for what element #Z=11#; it starts with an #'S'#. Every phyicist, chemist,and engineer regularly uses a Periodic Table.

Atomic Number 233

But of course there is another layer: the phenomenon of #'isotopes'#.

Let's take the simplest atom, hydrogen. Since #Z=1#, there is one nuclear proton, and around the nucleus an #'electron'#, a non-massive particle of near zero mass, and an opposite electronic charge to the protons is conceived to whizz about it. Some few hydrogen nuclei contain a neutron in their nucleus. The nucleus is still hydrogen, because that's how we define hydrogen, #Z=1#. We call this species #'deuterium'#, an isotope of hydrogen, and represent is as #'^2H#.

A smaller percentage of hydrogen nuclei contain 2 neutrons, to give the #'tritium'# isotope, #'^3H#. All of these are hydrogen isotopes. Most elements have a number of isotopes, and their mass is reported as the weighted average of the individual isotopic masses.

Confused yet? State your objections, and someone will try to help. Cheers and good luck with your studies.

Related questions