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The electrons are of such insignificant mass relative to that of the protons and neutrons, therefore we do not count them when calculating Atomic Mass, so the mass = 2 protons + 2 neutrons = mass number 4.
Wiki User
∙ 15y ago
Wiki User
∙ 7y ago1 amu is defined as one twelfth of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state.
1 amu = 1.660539040(20)×10−27 kg = 1.660539040(20)×10−24 g
so 3 amu = 4.98162×10−27 kg = 4.98162×10−24g.
Note that the electron associated with the atom contributes such a small amount of mass that it does not fall within the precision of the above numbers.
Wiki User
∙ 7y agomass = 3 amu
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What are the sizes of a hydrogen atom carbon atom and oxygen atom?
H has a mass number of 1 (one proton, no neutrons), Carbon has a mass number of 12 (6 neutrons, 6 protons) and O has a mass number of 16 (8 neutrons and 8 protons).
Which two particles make up most of the mass of a hydrogen-2 atom?
The proton and the neutron make up most of the mass of a hydrogen-2 atom.
Is Most of the mass in an atom is in electrons?
the mass of electrons is negligble the pe rcentage of an atom's mass comes from its protons and neutrons
How many neutrons on the middle shell of hydrogen?
Their are only 2 shells in the hydrogen atom.
What particles make up the mass of the atom?
Protons and neutrons, the particles that make up atomic nuclei, are the ones responsible for almost all of the mass of an atom. As the electron has less than 1/1800th the mass of a proton, a whole flock of electrons won't significantly change the mass of an atom. We look to the protons and neutrons (called nucleons when they are being considered as components of an atomic nucleus) to contribute to the mass of an atom, and they will be considered when we derive the atom weight of an element.
What is a direct consequence of the number of protons and neutrons in an atom's nuceuls?
Number of proton = atom numberfor example:Hydrogen has 1 proton and its atom number is also 1Number of neutrons + number of protons = mass numberfor example:Hydrogen have 1 proton and and NO neutrons, so the mass number is 1Helium has 2 protons and and 2 neutrons, so the mass number is 4
Is the mass of a hydrogen atom different from the mass of an oxygen atom?
all atoms have different masses Mass of an atom is due to protons and neutrons present in an atom and number of proton is something that distinguish between atoms, therefore mass of hydrogen is different to the mass number of oxygen, hydrogen's mass is 1 as it has only 1 proton and no neutrons, and oxygen mass's is 16 as it has 8 protons and 8 neutrons.
Where is the most of the mass in an atom?
Most of the mass in an atom is in the nucleus. The protons and neutrons are about the same weight, 1 amu. The elecrtons are 1/1840 of the mass of an proton. Neutrons are 2000 times heavier than electrons and protons have an equal mass of neutrons
An atom of tritium an isotope of hydrogen has 1 proton 2 neutrons and 1 electron What is its mass in amu?
Three
What are the sizes of a hydrogen atom carbon atom and oxygen atom?
H has a mass number of 1 (one proton, no neutrons), Carbon has a mass number of 12 (6 neutrons, 6 protons) and O has a mass number of 16 (8 neutrons and 8 protons).
An atom has an atomic mass of 101g and has 57 neutrons what is the atomic number?
If an atom has an atomic mass of 101g and 57 neutrons, then:Atomic Mass = (number of protions) + (number of neutrons) 101 = (X) + (57) or.... (101) - (57) = x 101-57=44 the element that has 44 as its atomic number would be RutheniumAs we know mass of atom is primaril constituted by the neutrons and protons,while the mass of electron is neglegible.Taking mass of proton equal to mass of neutron and both having a unit mass.we can say that mass of an atom is equal to the number of protons and neutrons multiplied with the mass of i proton/neutron.we are given mass of lithium =7=>(no. of neutron + no. of protons)*(mass of 1 proton/neutron)=7=>no. of neutrons + no. of protons *(1)=7=>no. of neutrons=7-no. of protons=>no. of neutrons=7-3 (atomic no=no. of protons)=>no. of neutrons=4
Which two particles make up most of the mass of a hydrogen-2 atom?
The proton and the neutron make up most of the mass of a hydrogen-2 atom.
what makes nearly all of the atom's mass?
The nucleolus.
Electrons has very little mass compared with the?
Compared with an atom. Protons and neutrons make up the nucleus of an atom with electrons in energy levels round the outside. If a proton has a mass of 1, then a neutron has a mass of very nearly the same (1) but an electron has a mass of 1/1836 or nearly two thousandth the mass of a proton.
Is a proton the least mass?
In an atom, there are 3 types of particles: protons, neutrons and electrons.Theoretically, protons and neutrons weight 1 Atomic Mass Unit. An electron weights 1/1836 of an Atomic Mass Unit. Therefore, in an atom, electrons weigh the least.
How can there be 1 proton with a hydrogen atom with a mass?
Protons and electrons both have mass. Therefore a hydrogen atom that contains one or both will have mass. (It will, however, be less massive than a hydrogen atom that also has neutrons.)
Is Most of the mass in an atom is in electrons?
the mass of electrons is negligble the pe rcentage of an atom's mass comes from its protons and neutrons
