What user do you miss the most? (bringing back an old topic)

[cyber]

John Dark Souls

[A Former User]

@O5-1-The-Founder You miss my girlfriend? Wowowowowo

[yourlocalkitkat]

@finn laws and duncan

[cyber]

@Calistaa bro we had a friendship

[A Former User]

@O5-1-The-Founder LMAO I like how you thought I actually implied something there

[A Former User]

Bheese is

[A Former User]

@Calistaa agree

[Harley]

@finn i miss @demi and laws

[cyber]

@Calistaa PAYDAY 2 is an action-packed, four-player co-op shooter that once again lets gamers don the masks of the original PAYDAY crew - Dallas, Hoxton, Wolf and Chains - as they descend on Washington DC for an epic crime spree.

The CRIMENET network offers a huge range of dynamic contracts, and players are free to choose anything from small-time convenience store hits or kidnappings, to big league cyber-crime or emptying out major bank vaults for that epic PAYDAY. While in DC, why not participate in the local community, and run a few political errands?

Up to four friends co-operate on the hits, and as the crew progresses the jobs become bigger, better and more rewarding. Along with earning more money and becoming a legendary criminal comes a character customization and crafting system that lets crews build and customize their own guns and gear.

Key Features
Rob Banks, Get Paid – Players must choose their crew carefully, because when the job goes down they will need the right mix of skills on their side.
CRIMENET – The dynamic contract database lets gamers pick and choose from available jobs by connecting with local contacts such as Vlad the Ukrainian, shady politician “The Elephant”, and South American drug trafficker Hector, all with their own agenda and best interests in mind.
PAYDAY Gunplay and Mechanics on a New Level – Firing weapons and zip tying civilians never felt so good.
Dynamic Scenarios – No heist ever plays out the same way twice. Every single scenario has random geometry or even rare events.
Choose Your Skills – As players progress they can invest in any of five special Skill Trees: Mastermind, Enforcer, Ghost, Technician and Fugitive. Each features a deep customization tree of associated skills and equipment to master, and they can be mixed and matched to create the ultimate heister.
More Masks than Ever – PAYDAY 2 features a completely new mask system, giving players the ability to craft their own unique mask with a pattern and color of their choice, resulting in millions of different combinations.
Weapons and Modifications – A brand new arsenal for the serious heister, covering everything from sniper and assault rifles to compact PDWs and SMGs. Once you’ve settled for a favorite, you can modify it with optics, suppressors, fore grips, reticles, barrels, frames, stocks and more, all of which will affect the performance of your weapon. There are also purely aesthetic enhancements - why not go for the drug lord look with polished walnut grips for your nine?
Play It Your Way – Each job allows for multiple approaches, such as slow and stealthy ambushes or running in guns blazing. Hit the target any way you want, each approach will provide a different experience.
A Long History of Additional Content – More than 70 updates since release, including new heists, characters, weapons and other gameplay features like driving cars and forklifts.

[A Former User]

@O5-1-The-Founder Atoms
Atom is a Greek word which means “indivisible.” The Greeks believed that matter can be broken down into very small invisible particles called atoms. Greek philosophers such as Democritus and John Dalton put forward the concept of the atom.

Democritus explained the nature of matter. He proposed that matter makes up all substances. Furthermore, he stated that atoms are constantly moving. They are invisible, minuscule particles that are different in shape, size, and temperature. And that we cannot destroy atoms.

Learn the concept of the Atomic number here in detail.

Later in the year 1808, John Dalton proposed the atomic theory. He explained the law of chemical combination. By the end of 18th and the early 20th centuries, many scientists developed and proposed several concepts on “atom.” Namely, J.J Thomson, Gold stein, Rutherford, and Bohr among others.

Atom is the smallest unit of matter. It consists of a positively charged center termed as “nucleus”. Also, negatively charged electrons surround the central nucleus. Even though an atom is the smallest unit of matter it retains all the chemical properties of an element. For example, silver atoms and a few other constituents make up a silver spoon. The tiny subatomic particles that compose a silver atom define the properties of the silver atom.

Atoms are further arranged and organized to form larger structures known as molecules. Atoms and molecules adhere to the general chemistry and physics rule even when they are part of living human body. Now let us study the structure of atom to further understand how the atoms react, behave and interact.

Learn more about Thomson’s Model of Atom in detail.

Structure of Atom
The structure of atom consists of two parts:

an atomic nucleus
extra nucleus part
Structure of atom
The tiny atomic nucleus is the center of an atom. It constitutes positively charged particles “protons” and uncharged particles “neutrons.” On the other hand, the extra nucleus part is a much larger region. It consists of a cloud of negatively charged particles called an electron. Electrons revolve in orbit around the nucleus. The attraction between the protons and electrons holds the structure of atom together.

Learn how electrons are distributed in different shells in detail here.

Generally, all atoms except hydrogen consist of these three subatomic particles. Hydrogen is an exception to all atoms as it contains just one proton and one electron but lacks neutrons. The number of protons indicates what element an atom is. Whereas the number of electrons indicates the type of reactions that will happen in an atom.

The atomic nucleus in the structure of atom consists of a fixed number of protons. Also, the proton attracts the same number of electrons thereby making an atom electrically neutral. The addition or removal of electrons from an atom results in the formation of ions.

Learn about the Disadvantages of Rutherford’s Atomic Model here.

You can download Structure of Atom Cheat Sheet by clicking on the download button below

Structure of Atom
Discovery of an Electron
In the year 1897, a British Physicist named J.J Thompson proposed that an atom constitutes of at least one negatively charged particle. He named it “corpuscles” which was later called “electron.”

‘e’ represents an electron and it contributes to the negative charge of an atom. The absolute charge of an electron is the negative charge of 1.6×10-19 coulombs. The relative mass of an electron is 1/1836. Furthermore, the mass of an electron is 0.

Discovery of Proton
Proton was discovered by Rutherford when he conducted the famous gold foil experiment. In 1886 Goldstein discovered the presence of positively charged rays while experimenting with the discharged tube using perforated cathode. The rays were named as anode rays or canal rays. A series of experiments led to the discovery of protons. Protons are the particles that contribute to the positive charge of the atom.

“p” represents proton. The absolute charge of a proton is the positive charge of 1.6×10-19 coulomb. The mass of a proton is 1.6×10 -24 g and is considered 1 that is mass of a hydrogen atom.

Discovery of Neutron
The discovery of neutron didn’t happen until the year 1932. James Chadwick discovered the neutron. He used scattered particle to calculate the mass of the neutral particle. The subatomic particle “neutron” is present in an atom’s nucleus.“n” represents neutron. It is a neutral particle. The mass of a neutron is 1.6 x 10 -24 g.

Gram is not an appropriate unit for the calculation of such tiny subatomic particles. But Dalton or amu (atomic mass unit) is appropriate. Furthermore, protons and neutrons have a mass that is nearly 1 amu.

Learn more about Bohr’s Atomic Model here.

Solved Question for You
Question: What is the net charge of an atom?

Ans: There is no net charge of an atom. The charge of electrons is negative whereas the charge of protons is positive. The equal positive charge of the proton and the negative charge of the electron cancel each other. Therefore, the atom has no net charge. In a neutral atom, the number of electrons revolving around the nucleus and the number of protons inside the nucleus are equal in number.

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Structure of Atom
ProtonsElectron ConfigurationQuantum NumbersShapes of Atomic OrbitalsEnergies of OrbitalsTowards Quantum Mechanical Model of AtomEmission and Absorption SpectraDevelopment Leading to Bohr’s Model of AtomAtomic ModelsSub-Atomic Particles
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heap.identify(‘unique_identifier’);

[A Former User]

@ᴘᴀᴄᴋɢᴏᴅ yea im not reading that

[A Former User]

@Izzy-Lol atom
matter

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Last Updated: Jan 5, 2023 • Article History
shell atomic model
shell atomic model
See all media
Key People: Ernest Rutherford Niels Bohr Lev Davidovich Landau Steven Chu William D. Phillips
Related Topics: subatomic particle radioactivity isotope atomism periodic table
Top Questions
What is an atom?
Are all atoms the same size?
What does the mass of an atom consist of?
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Summary
Read a brief summary of this topic
atom, smallest unit into which matter can be divided without the release of electrically charged particles. It also is the smallest unit of matter that has the characteristic properties of a chemical element. As such, the atom is the basic building block of chemistry.

Investigate varying electron configurations in electron shells around an atom’s nucleus
Investigate varying electron configurations in electron shells around an atom’s nucleusSee all videos for this article
Most of the atom is empty space. The rest consists of a positively charged nucleus of protons and neutrons surrounded by a cloud of negatively charged electrons. The nucleus is small and dense compared with the electrons, which are the lightest charged particles in nature. Electrons are attracted to any positive charge by their electric force; in an atom, electric forces bind the electrons to the nucleus.

Because of the nature of quantum mechanics, no single image has been entirely satisfactory at visualizing the atom’s various characteristics, which thus forces physicists to use complementary pictures of the atom to explain different properties. In some respects, the electrons in an atom behave like particles orbiting the nucleus. In others, the electrons behave like waves frozen in position around the nucleus. Such wave patterns, called orbitals, describe the distribution of individual electrons. The behaviour of an atom is strongly influenced by these orbital properties, and its chemical properties are determined by orbital groupings known as shells.

This article opens with a broad overview of the fundamental properties of the atom and its constituent particles and forces. Following this overview is a historical survey of the most influential concepts about the atom that have been formulated through the centuries. For additional information pertaining to nuclear structure and elementary particles, see subatomic particles.

Magnified phytoplankton (pleurosigma angulatum) seen through a microscope, a favorite object for testing the high powers of microscopes. Photomicroscopy. Hompepage blog 2009, history and society, science and technology, explore discovery
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Science: Fact or Fiction?
Atomic model
Most matter consists of an agglomeration of molecules, which can be separated relatively easily. Molecules, in turn, are composed of atoms joined by chemical bonds that are more difficult to break. Each individual atom consists of smaller particles—namely, electrons and nuclei. These particles are electrically charged, and the electric forces on the charge are responsible for holding the atom together. Attempts to separate these smaller constituent particles require ever-increasing amounts of energy and result in the creation of new subatomic particles, many of which are charged.

As noted in the introduction to this article, an atom consists largely of empty space. The nucleus is the positively charged centre of an atom and contains most of its mass. It is composed of protons, which have a positive charge, and neutrons, which have no charge. Protons, neutrons, and the electrons surrounding them are long-lived particles present in all ordinary, naturally occurring atoms. Other subatomic particles may be found in association with these three types of particles. They can be created only with the addition of enormous amounts of energy, however, and are very short-lived.

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All atoms are roughly the same size, whether they have 3 or 90 electrons. Approximately 50 million atoms of solid matter lined up in a row would measure 1 cm (0.4 inch). A convenient unit of length for measuring atomic sizes is the angstrom (Å), defined as 10−10 metre. The radius of an atom measures 1–2 Å. Compared with the overall size of the atom, the nucleus is even more minute. It is in the same proportion to the atom as a marble is to a football field. In volume the nucleus takes up only 10−14 metres of the space in the atom—i.e., 1 part in 100,000. A convenient unit of length for measuring nuclear sizes is the femtometre (fm), which equals 10−15 metre. The diameter of a nucleus depends on the number of particles it contains and ranges from about 4 fm for a light nucleus such as carbon to 15 fm for a heavy nucleus such as lead. In spite of the small size of the nucleus, virtually all the mass of the atom is concentrated there. The protons are massive, positively charged particles, whereas the neutrons have no charge and are slightly more massive than the protons. The fact that nuclei can have anywhere from 1 to nearly 300 protons and neutrons accounts for their wide variation in mass. The lightest nucleus, that of hydrogen, is 1,836 times more massive than an electron, while heavy nuclei are nearly 500,000 times more massive.

Basic properties
Atomic number
The single most important characteristic of an atom is its atomic number (usually denoted by the letter Z), which is defined as the number of units of positive charge (protons) in the nucleus. For example, if an atom has a Z of 6, it is carbon, while a Z of 92 corresponds to uranium. A neutral atom has an equal number of protons and electrons so that the positive and negative charges exactly balance. Since it is the electrons that determine how one atom interacts with another, in the end it is the number of protons in the nucleus that determines the chemical properties of an atom.

Atomic mass and isotopes
isotopes of hydrogen
isotopes of hydrogen
The number of neutrons in a nucleus affects the mass of the atom but not its chemical properties. Thus, a nucleus with six protons and six neutrons will have the same chemical properties as a nucleus with six protons and eight neutrons, although the two masses will be different. Nuclei with the same number of protons but different numbers of neutrons are said to be isotopes of each other. All chemical elements have many isotopes.

It is usual to characterize different isotopes by giving the sum of the number of protons and neutrons in the nucleus—a quantity called the atomic mass number. In the above example, the first atom would be called carbon-12 or 12C (because it has six protons and six neutrons), while the second would be carbon-14 or 14C.

The mass of atoms is measured in terms of the atomic mass unit, which is defined to be 1/12 of the mass of an atom of carbon-12, or 1.660538921 × 10−24 gram. The mass of an atom consists of the mass of the nucleus plus that of the electrons, so the atomic mass unit is not exactly the same as the mass of the proton or neutron.

The electron
Charge, mass, and spin
Millikan oil-drop experiment
Millikan oil-drop experiment
See how physicist Robert Millikan devised a method for measuring the electric charge of single electrons
See how physicist Robert Millikan devised a method for measuring the electric charge of single electronsSee all videos for this article
Scientists have known since the late 19th century that the electron has a negative electric charge. The value of this charge was first measured by the American physicist Robert Millikan between 1909 and 1910. In Millikan’s oil-drop experiment, he suspended tiny oil drops in a chamber containing an oil mist. By measuring the rate of fall of the oil drops, he was able to determine their weight. Oil drops that had an electric charge (acquired, for example, by friction when moving through the air) could then be slowed down or stopped by applying an electric force. By comparing applied electric force with changes in motion, Millikan was able to determine the electric charge on each drop. After he had measured many drops, he found that the charges on all of them were simple multiples of a single number. This basic unit of charge was the charge on the electron, and the different charges on the oil drops corresponded to those having 2, 3, 4,… extra electrons on them. The charge on the electron is now accepted to be 1.602176565 × 10−19 coulomb. For this work Millikan was awarded the Nobel Prize for Physics in 1923.

The charge on the proton is equal in magnitude to that on the electron but opposite in sign—that is, the proton has a positive charge. Because opposite electric charges attract each other, there is an attractive force between electrons and protons. This force is what keeps electrons in orbit around the nucleus, something like the way that gravity keeps Earth in orbit around the Sun.

The electron has a mass of about 9.109382911 × 10−28 gram. The mass of a proton or neutron is about 1,836 times larger. This explains why the mass of an atom is primarily determined by the mass of the protons and neutrons in the nucleus.

The electron has other intrinsic properties. One of these is called spin. The electron can be pictured as being something like Earth, spinning around an axis of rotation. In fact, most elementary particles have this property. Unlike Earth, however, they exist in the subatomic world and are governed by the laws of quantum mechanics. Therefore, these particles cannot spin in any arbitrary way, but only at certain specific rates. These rates can be 1/2, 1, 3/2, 2,… times a basic unit of rotation. Like protons and neutrons, electrons have spin 1/2.

Particles with half-integer spin are called fermions, for the Italian American physicist Enrico Fermi, who investigated their properties in the first half of the 20th century. Fermions have one important property that will help explain both the way that electrons are arranged in their orbits and the way that protons and neutrons are arranged inside the nucleus. They are subject to the Pauli exclusion principle (named for the Austrian physicist Wolfgang Pauli), which states that no two fermions can occupy the same state—for example, the two electrons in a helium atom must have different spin directions if they occupy the same orbit.

Because a spinning electron can be thought of as a moving electric charge, electrons can be thought of as tiny electromagnets. This means that, like any other magnet, an electron will respond to the presence of a magnetic field by twisting. (Think of a compass needle pointing north under the influence of Earth’s magnetic field.) This fact is usually expressed by saying that electrons have a magnetic moment. In physics, magnetic moment relates the strength of a magnetic field to the torque experienced by a magnetic object. Because of their intrinsic spin, electrons have a magnetic moment given by −9.28 × 10−24 joule per tesla.

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[A Former User]

@ᴘᴀᴄᴋɢᴏᴅ -_-

[A Former User]

@Izzy-Lol ehehehehe

[Ŵølƒy_Hellhøund_Likes_Pizza]

@Izzy-Lol same

[A Former User]

@O5-1-The-Founder Ok