Structure of Atoms, Mass Number and Isotopes

The atom comprises protons, neutrons and electrons. The protons and neutrons are enclosed in a central nucleus that is at the center of the atom, together they are collectively known as nucleons. All of the mass of an atom is said to be in the nucleus because electrons weigh little.

The table below shows some comparisons between protons, neutrons and electrons:

Sub-atomic particle
Relative Mass
Relative Charge


Finding protons, neutrons or mass number:-
Given the values of two of these variables one can transpose the following formula to find the third variable.

     Mass # (A) = # of protons (z) + # of neutrons
Note: The names may vary for e.g. number of protons can sometimes be called atomic number and mass number can be called nucleon number.

For example calculate the number of neutrons in this atom:

If you look at the diagram closely you will see that they have given you two value the mass number and the number of protons (in this example the term atomic number is used instead). Right away one can see that all is needed is to transpose the previous formula to find number of neutrons.

    Mass number = number of protons or atomic number + number of neutrons
             19          =         9     +      N

When done transposing this formula for N you should get:

                      19 – 9 = 9 – 9 + N
                      19 – 9 = 0 + N
                            10 = N
                         =>N = 10

Finding the number of electrons:-

It is relatively easy to find the number of electrons because no calculation is needed. Atoms are neutral the positive charges from the protons will balance the negative charges of the electrons. Therefore the electrons would have to be the same number as that of the protons.
     Number of protons = Number of electrons.

These are atoms of the same element with the same atomic number but different mass numbers. This is due to a difference in the amount of neutrons present in each atom; the protons however do not change. For example there are three isotopes of carbon namely: Carbon-12, Carbon-13 and carbon-14(the numbers represent mass) their protons remain the same being 6 but the neutrons vary being 6, 7 and 8 respectively.

Relative Atomic Mass:
The relative atomic mass of an element can be defined as the ratio of the mass of an atom of the element to one twelfth the mass of carbon-12.

The relative atomic mass can be found using the following formula:

     R.A.M = Mass of one atom of the element   × 12
                     Mass of one atom of Carbon-12

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7 Response to Structure of Atoms, Mass Number and Isotopes

February 21, 2018 at 11:13 AM

3d bioprinting = Immortality = go to stars

February 21, 2018 at 11:28 AM

...interstellar travel constant acceleration (Sun-Deneb:1000g)... Earth...the 2 ships that will go formation flying for mutual assisting if there are problems...indestructible structures made of Hexapentas material, awaiting in airport the arrival of passengers... Day 1: zero-speed... THE SHIPS TAKEOFF►...navigation computer places on screen the spacecraft in the center of sphere...spherical\tridimensional\spatial Heading: Deneb... Antimatter rocket engines...ON... Here we go...goooooo!...1g...10g...100g...constant acceleration cruise: 1000g (9.8 kms/sec²)... Inside the living areas (the same as going submerged in water: constant acceleration downwards...less...constant thrust, constant acceleration, from water upwards)...the gravitational transformers, perfectly synchronized with the acceleration, running: 1000g constant acceleration toward the floor ↓↓(motors)↓↓...less...999g constant acceleration toward the ceiling ↑↑(gravitational transformers)↑ = 1g constant acceleration toward the floor↓... 8.5 hours: light-speed = 1c...the fusion reactor as an artificial sun illuminating the immense Vital Support Gardens to lowering, from their comfortable apartments, cheerful passage to the pool...the electromagnetic shield anti-radiation...antigravity fields generator run forward, working: light objects away from the path of the ship...and trajectory ship away from the heavy object...superluminal-speed > 1c... 42.5 hours: reaches hyperluminal-speed = 5c... Day 508: Half Journey...1000 light years...high hyperluminal-speed = 1435.39c... OFF engines...a few minutes of weightlessness during maneuver...the ship rotates 180º around its axis...motors ON again and...◄STARTS TO BRAKE... Day 1017 (2.79 years): End Path party...2000 light The forever young passage of the 1st Immortal Generation (3D Bioprinting...Telomerase...modified Biological Timers...) disembarks at destination: an extra-stellar planet which came errant to orbit of Deneb giant.

February 22, 2018 at 11:18 AM

(4)...interstellar travel (thousands G of constant acceleration)... What is a Force?... Gravity...two objects attract between them emitting gravitons, how two pirate-ships hooked by ropes with hooks from the other... Each emitted graviton perhaps would go invisibly united to its emitter object, such as if would go an elastic cord with infinite length and when arrives till the other object, by far that it is, "knows" toward where has that "pulling"...never are confused the gravitons emitted by different sources "pulling" toward do not is... The gravitons that come from Andromeda they "pull" toward Andromeda, and do not toward the Magellanic Clouds... That graviton comes climbing toward the steel object which falls from a tower...when arrives to the object, what finds?...sighted from its perspective finds which the object in reality does not exist...only "sees" a vacuum, here a nucleus of protons and neutrons...far over there some electrons in orbit...((the distance between Earth and Moon is enormously major than the diameters Earth + Moon; the distance between an atomic nucleus and its orbital electrons is enormously major than the diameters of all their subatomic particles added))... Where "hooking for pulling" from this object which does not exist?, asks itself...also asks itself from where comes, how went emitted because over there also only was vacuum and some subatomic particles here and there.. Ah, I know..."will hook" in the magnetic force lines which go away for this huge vacuum joining the nuclei of protons (+) with their far electrons (-), in these force lines made with Photons emitted from those nuclei and electrons... but, they are lines of electromagnetic force and I am a graviton... Ah, from there comes a graviton of here, from where comes?, perhaps from interior of some Proton where the gluons, what an adhesive!...indestructibly join quarks to form it...and goes to the place from where I come for make the same, "hooking for pulling". So that perhaps...Graviton hooks in Proton that seems strong... The Gravitational Force how solution...someday all spacecrafts always will go to thousands G of constant acceleration... The Universe is just there for us... What is a Force?...who emits it?...where it "hooks"?...

February 25, 2018 at 9:29 AM

(4b)...interstellar travel (thousands G of constant acceleration)... The entire Universe gyrating. The "phantom position"... LMC galaxy moves around the Milky Way... When it is in an orbital point emits its gravitons toward here...when it is to quite a few degrees from point before those emitted gravitons do not can "pulling" toward the already "phantom position" where LMC is not placed now, so that the Gravitons must have a quality of trajectories reorganization it depends moving of the object, the new emitted would go away auto-correcting the trajectories of the gravitons before for the attraction always being toward the actual position... Andromeda and Milky Way... The Photons it transit by the "phantom position" because we see Andromeda not only how it was 2 million years ago, but also "where it was" at that time. At different way those emitted Gravitons in each place then must go away course actualizing among them... Matter/Antimatter annihilation rockets... to 9800 kms/sec²... Day 508: Half Journey...1 million light years...high hyperluminal-speed = 0.0455 light years/sec... In 2.79 years, here is Andromeda... spherical\tridimensional\spatial Heading...intergalactic navigation in Starships to thousands G of constant acceleration...

February 27, 2018 at 11:04 AM

...interstellar travel constant acceleration (times to reach light-speed)... 1g (9.8 mts/sec²)=354 days ...↓... 0.5g (4.9 mts/sec²)=1.94 years ...↓... 0.25g (2.45 mts/sec²)=3.88 years ...↓... 0.1g (98 cms/sec²)=9.7 years ...↓... 0.01g (9.8 cms/sec²)=97 years ...↓... 0.001g (9.8 mms/sec²)=970 years ______ Huge constant acceleration the ship, living areas to 1g: inside the living areas..."the same as going submerged in water"...↓↓↓↓g(motors)...less...↑↑↑g (gravitational transformers)=↓g... ...↨... 2g (19.6 mts/sec²)=177 days ...↨... 10g (98 mts/sec²)=35.4 days ...↨... 100g (980 mts/sec²)=3.54 days ...↨... 1000g (9.8 kms/sec²)=8.5 hours ...↨... 10000g (98 kms/sec²)=51 minutes ...↨... 50000g (490 kms/sec²)=10.2 minutes ...↨... 100000g (980 kms/sec²)=5.1 minutes ...↨... 1 million G (9800 kms/sec²)=30.6 seconds... ((typewrite: interstellar travel constant acceleration))

March 17, 2018 at 12:08 PM (orbital station bike wheel-1g)... geostationary orbit, a huge "bike-wheel" is gyrating around its own axis for have 1g-centrifugal. Wheel held in place with 4 CABLES (each cable with a track for Train, for both trains crossing ↓↑) FORMING THE STRUCTURE OF A RHOMBUS♦ (minor diagonal of rhombus is the gyration-axis of the Station-Wheel)...rhombus´s below, the carbon nanotubes Track towards Earth...rhombus´s below, the Cable towards a higher counterweight... if...WHEEL´s RADIUS = 250 mts... Wheel gyration´s Axis length = rhombus´s minor diagonal = ½ Wheel´s radius = 125 mts (axis could be a resistant hollow tube with for example 20 mts in diameter with an adequate wall´s thickness, hollow which could serving how tank of anything, e.g. air, or tank of frozen water storage no totally full, for volume expansion from liquid to ice without tank, Axis, breaking, thawing using solar-heat)... Cable´s length of the rhombus´s side = Wheel diameter = 500 mts ((also how Wheel´s supporting, instead of a rhombus, can be a narrow Rectangular structure ▄▄▄▄▄▄ of rigid girder with dimension sides slightly majors than Wheel´s diameter and wide, e.g. Wheel´s diameter 500 mts and wide 50 mts...rectangle´s sides: 510 mts length, 60 mts wide. Rectangle with a cable/track (length=Wheel´s diameter) in each vertex, forming a long isosceles triangle ───◄at both rectangle´s minor sides►───)). Wheel´s ZONE-1g: habitable length = 1571 mts*50 mts wide (separation at both sides between Cable and Circumference of the gyratory Wheel, approx.= 5 mts, adjusting this separation installing an Axis with major or minor length, as much as shorter Axis...stronger and, for easy train´s passing, an angle nearer to 180º value in both rhombus´s-vertex, minor diagonal, where are the Big Soundless-♫-Bearings of Axis´s-insertion...a few Electrical Motors fed with Solar-Energy maintain automatically the gyration-speed counteracting the slow braking by friction from the Bearings...besides of Bearings: main Maglev system also for the gyration and Axis´s supporting, leaving the Bearings only how secondary security system...with a slight roominess between each Bearing and its exterior subjection, into the roominess all around...little solid Pistons radial extensible and retractable... Axis´s subjection: extensible ON, with Bearings; extensible OFF, with Maglev. With a sufficient cables tension coming from the counterweight, if Axis resists: the rhombus structure is undeformable)*10 Floors with 25 mts in height each one, gyrating 360º each 31 seconds, angular-speed = 11.61º/sec, linear-speed (tangential) = 182 kms/h... Station-Wheel´s GYRATION: AXIS IN PERPENDICULAR (90º) ORIENTATION TO THE ORBITAL TRAJECTORY...and so, while Station-Wheel follows its geostationary orbit, the Wheel does Not change the spatial-orientation of its axis, and thus there are Not Precession forces actuating (and thus there is Not torsion´s force against Track)...

March 21, 2018 at 2:29 PM

(2) (orbital station bike wheel-1g)... Wheel with maneuver´s tangential-rockets for gyration´s start, or...gyration emergency stop...and maneuver´s axial-rockets for reorientation of Wheel´s axis, if it is necessary: because the Earth axis slightly and very slowly goes oscillating cyclically due to nutation and precession...that oscillation evidently produces transversal traction pulling of the Track towards aside from its anchoring on equator, thus would have an also slight pendular movement side to side and it would produce precession´s movements of the Wheel´s axis and thus a not wished torsion of the Track...but the system must supporting lateral charges, in the same orbital plane and thus without precession´s problems on the Wheel´s axis, of acceleration against W→Track←E produced by the Coriolis effect when movement´s direction is perpendicular to the gyration´s axis, that lateral charge is maximum on equator (there, a vertical movement is perpendicular tø Earth axis) and zero on poles (there, a vertical movement is parallel tø Earth axis); upwards charge to West, downwards charge to East; the gyroscopic-rigidity contributes for maintaining the gyration-axis perpendicular to the orbital trajectory... When the Maglev Train slowly arrives (Train with one opened ╚╝ side in its technical maglev-zone train´s all along over Track for can passing for both tracks: main-Track/rhombus-track/again main-Track), using now cogwheels on Zipper-Track (zippers installed on the same Maglev-Track), Train stops in Geo 0g-Station placed over one Extreme of the Gyration-Axis, next to «Port for Spacecrafts»... Passengers disembark and entering into gyratory circular corridor, they take now the interior-elevator of one of the Wheel´s hollow-radius (also could be an exterior-elevator running for a simple zipper-radius), and tunnel "descending" till Hotel into the final Zone-1g...where while Station-Wheel goes turning, the immense O2 producer Hydroponics Garden receives a filtered Sun light...and there are Earth´s awesome views.

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