7 electrons Valence electrons are the number of electrons present in the outermost shell of an atom. Now, the last shell of chlorine atom has 7 electrons in it. Therefore, there are 7 valence electrons present in an chlorine atom.
- 0.1 Is chlorine a valency 1 or 2?
- 0.2 Why does chlorine have 8 valence electrons?
- 1 Is chlorine a valency 7?
- 2 Can chlorine have 10 electrons?
- 3 Does chlorine need 8 electrons?
- 4 Which has 2 or 8 valence electrons?
- 5 Why is chlorine 2 8 7?
- 6 Do all elements need 8 valence electrons?
- 7 Is chlorine 2 8 7?
- 8 What is 7 in chlorine?
- 9 Why can chlorine form 7 bonds?
- 10 Why is chlorine in group 7?
- 11 Why is chlorine in group 7 of the periodic table?
Why does chlorine have 7 valence electrons?
Answer and Explanation: Chlorine is in group 17, the halogens, which all have 7 valence electrons. Because halogens only require one more electron to fill their valence shell, several of them form diatomic molecules with two atoms of the same element. These are the natural states of these elements.
Can chlorine have 8 valence electrons?
Therefore, the total number of valence electrons in chlorine ion is Eight. Hence option (B) is correct.
Is chlorine a valency 1 or 2?
Chlorine has a valency of 1, Chlorine has an atomic number of 17.
Chlorine’s electrical configuration is Ne 3 s 2 3 p 5, which can also be represented as 2, 8, 7, This demonstrates that chlorine’s outermost shell has seven valence electrons. If there are more than four valence electrons, the valency can be determined as follows: valence electron -8 valence valence valence valence valence val As a result, chlorine has a valency of 7-8, which is 1, As a result, chlorine has a valency of 1,
Why does chlorine have 8 valence electrons?
Number of valence electrons in Chlorine ion are: (a) 16 (b) 8 (c) 17 (d) 18 Join Vedantu’s FREE Mastercalss Answer Verified Hint: Chlorine is a chemical element with the atomic number 17 and the symbol Cl. It is the second-lightest of the halogens, appearing on the periodic table between fluorine and bromine, and its characteristics are largely midway between them.
Complete answer: Note:
A valence electron is an outer shell electron connected with an atom that can participate in the creation of a chemical bond if the outer shell is not closed; in a single covalent connection, both atoms contribute one valence electron to create a shared pair in chemistry and physics.
- The existence of valence electrons can affect an element’s chemical characteristics, such as its valence—whether or not it can bind with other elements and, if so, how easily and how many times.
- In this sense, the reactivity of a particular element is strongly reliant on its electrical arrangement.Valence electrons are electrons in the outer shells that are not completely filled.
Chlorine has an atomic number of 17. Here is the electrical configuration of chlorine.\ As a result, it possesses two electrons in its innermost shell, eight electrons in its second shell, and seven electrons in its outermost shell. As a result, the chlorine atom has seven valence electrons.
- The shell of the chlorine ion ($C $) has 18 electrons.
- There are eight valence electrons in all.A valence electron may receive or release energy in the form of a photon, much like a core electron.
- Atomic excitation occurs when an energy gain causes an electron to migrate (jump) to an outer shell.
- Alternatively, the electron can break free from its linked atom’s shell, resulting in ionisation and the formation of a positive ion.
When an electron loses energy (and so emits a photon), it might migrate to an inner shell that isn’t completely occupied. : Number of valence electrons in Chlorine ion are: (a) 16 (b) 8 (c) 17 (d) 18
Does chlorine have 7 or 8 valence electrons?
Valence electrons are the number of electrons present in the outermost shell of an atom. Now, the last shell of chlorine atom has 7 electrons in it. Therefore, there are 7 valence electrons present in an chlorine atom.
Is chlorine a valency 7?
Valency of \\ is \\ and not \\, Give reasons. Join Vedantu’s FREE Mastercalss Answer Verified Hint: The number of valence electrons is a measure of the number of electrons that are present in the outermost shell of an atom but valency is not the same as the number of valence electrons in an atom. It actually depends on the nature of the element being studied.
Complete answer: Note:
Chlorine is a halogen and belongs to the seventeenth group of the modern periodic table. It is the second member of the group after fluorine and is sufficiently electronegative to be called a non-metal. There are a total of seven valence electrons present in the outermost shell (valence shell) of the atom as the outer electronic configuration of chlorine atoms is \,
- Valence electrons are not the same as the valency of an atom because valency actually indicates the number of electrons contributed or gained by the particular atom in a reaction.
- Thus, valency actually represents the electrons needed or released by an atom to form a bond and complete its octet which may or may not be equal to the number of valence electrons.Chlorine has a small size and experiences high nuclear charge therefore it does not have the ability to lose electrons.
In order to gain its octet, it must donate seven of its electrons or accept an electron. Due to its electronegativity, chlorine gains an electron rather than losing seven of its electrons (which is a difficult process for even electropositive elements.
Therefore chlorine has its valency equal to one and not seven.We mainly talk about the valency or valence shell configuration because the electrons present in the outermost shell are the ones that can participate in a reaction and are least affected by the nuclear pull. Also the shells before the valence shell are always completely filled.
How Many Valence Electrons Does Chlorine Have?||Number of Valence Electrons in Chlorine
: Valency of \\ is \\ and not \\, Give reasons.
Can you have 10 valence electrons?
Species with Expanded Octets – Examples of molecules with more than an octet of electrons are phosphorus pentafluoride (PF 5 ) and sulfur hexafluoride (SF 6 ). Phosphorus pentafluoride is a gas at room temperature. It consists of PF 5 molecules in which each fluorine atom is bonded to the phosphorus atom. Since each bond corresponds to a shared pair of electrons, the Lewis structure is P is connected to two equally spaced F atoms below it and three equally spaced F atoms above it. The dot diagram shows that P has a total of ten electrons on its valence. Instead of an octet the phosphorus atom has 10 electrons in its valence shell. Sulfur hexafluoride (also a gas) consists of SF 6 molecules. Its structure is Sulfur bonded to six Fluorine that are equally spaced out from one another. The dot diagram shows that sulfur has 12 electrons in its valence shell. Here the sulfur atom has six electron pairs in its valence shell. An atom like phosphorus or sulfur which has more than an octet is said to have expanded its valence shell,
- This can only occur when the valence shell has enough orbitals to accommodate the extra electrons.
- For example, in the case of phosphorus, the valence shell has a principal quantum number n = 3.
- An octet would be 3 s 2 3 p 6,
- However, the 3 d subshell is also available, and some of the 3 d orbitals may also be involved in bonding.
This permits the extra pair of electrons to occupy the valence ( n = 3) shell of phosphorus in PF 5, Expansion of the valence shell is impossible for an atom in the second period because there is no such thing as a 2 d orbital. The valence ( n = 2) shell of nitrogen, for example, consists of the 2 s and 2 p subshells only.
Can chlorine have 10 electrons?
From the figure, F has 8, but Cl has 10. ‘Every element wants 8 valence electrons’ is just a simplified description for people to get started with chemistry. Octet rule has its limits and many exceptions, ClF3 is a typical example of hypervalent molecules.
Can chlorine hold 12 valence electrons?
Example – The formula for table salt is NaCl. It is the result of Na + ions and Cl – ions bonding together. If sodium metal and chlorine gas mix under the right conditions, they will form salt. The sodium loses an electron, and the chlorine gains that electron.
In the process, a great amount of light and heat is released. The resulting salt is mostly unreactive — it is stable. It won’t undergo any explosive reactions, unlike the sodium and chlorine that it is made of. Why? Referring to the octet rule, atoms attempt to get a noble gas electron configuration, which is eight valence electrons.
Sodium has one valence electron, so giving it up would result in the same electron configuration as neon. Chlorine has seven valence electrons, so if it takes one it will have eight (an octet). Chlorine has the electron configuration of argon when it gains an electron.
- The octet rule could have been satisfied if chlorine gave up all seven of its valence electrons and sodium took them.
- In that case, both would have the electron configurations of noble gasses, with a full valence shell.
- However, their charges would be much higher.
- It would be Na 7- and Cl 7+, which is much less stable than Na + and Cl -,
Atoms are more stable when they have no charge, or a small charge.
Why is chlorine negative 1?
Show students how calcium and chlorine atoms bond to form the ionic compound calcium chloride. – Tell students that there is another common substance called calcium chloride (CaCl 2 ). It is the salt that is used on icy sidewalks and roads. Explain that when calcium and chlorine react they produce ions, like sodium and chlorine, but the calcium ion is different from the sodium ion.
Ask students: What ions do you think CaCl 2 is made of? One calcium ion and two chloride ions. Project the animation Calcium chloride Ionic Bond. Point out that the calcium loses two electrons, becoming a +2 ion. Each of the two chlorine atoms gains one of these electrons, making them each a −1 ion. Help students realize that 1 calcium ion bonds with 2 chloride ions to form calcium chloride (CaCl 2 ), which is neutral.
Some atoms gain or lose more than 1 electron. Calcium loses 2 electrons when it becomes an ion. When ions come together to form an ionic bond, they always join in numbers that exactly cancel out the positive and negative charge. Project the image Calcium chloride Ionic Bond.
- One calcium and two chlorine are near each other.
- The protons of the calcium atom attract the electrons from the chlorine atom. The protons of the two chlorine atoms attract the electrons from the calcium atom more strongly as shown by the thicker arrows.
- During the interactions between the atoms, the two electrons in calcium’s outer energy level are transferred to the outer energy level of each of the chlorine atoms.
- Since calcium lost two electrons, it has 20 protons, but only 18 electrons. This makes calcium a positive ion with a charge of 2+. Since each chlorine atom gained an electron, they each have 17 protons and 18 electrons. This makes each chloride a negative ion with a charge of −1.
- Oppositely charged ions attract each other, forming an ionic bond. The bonded ions are more stable than the individual atoms were.
What rule is 8 valence electrons?
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Page ID 37382 The octet rule refers to the tendency of atoms to prefer to have eight electrons in the valence shell, When atoms have fewer than eight electrons, they tend to react and form more stable compounds. When discussing the octet rule, we do not consider d or f electrons.
Does chlorine need 8 electrons?
Lewis Dot of the Chlorate Ion ClO3-
- Lewis Dot of the Chlorate Ion
- ClO 3 –
Chlorine does not follow the octet rule. It will hold more than 8 electrons.
- Chlorine having valence electrons in the 3rd energy level, will also have access to the 3d sublevel, thus allowing for more than 8 electrons.
- Elements in the first 2 periods of the Periodic Table do not have access to the d sublevel and must adhere to the octet (or duet H and He) rule,
- The chlorate ion cannot be satisfactorily represented by just one Lewis Dots structure.
- All the bonds are the same length and must be thought of as a hybrid of multiple resonance structures.
from http://treefrog.fullerton.edu/chem/LS/ClO3neg1LS.html : Lewis Dot of the Chlorate Ion ClO3-
Which has 2 or 8 valence electrons?
Octet Rule – The noble gases are unreactive because of their electron configurations. The noble gas neon has the electron configuration of \(1s^2 \: 2s^2 \: 2p^6\). It has a full outer shell and cannot incorporate any more electrons into the valence shell. The other noble gases have the same outer shell electron configuration, even though they have different numbers of inner-shell electrons. Figure \(\PageIndex \): Electron configuration of neon atom. (Credit: Joy Sheng; Source: CK-12 Foundation; License: CC BY-NC-SA 3.0(opens in new window) ) American chemist Gilbert Lewis (1875-1946) used this observation to explain the types of ions and molecules that are formed by other elements.
He called his explanation the octet rule, The octet rule states that atoms tend to form compounds in ways that give them eight valence electrons, and thus the electron configuration of a noble gas. An exception to an octet of electrons is in the case of the first noble gas, helium, which only has two valence electrons.
This primarily affects the element hydrogen, which forms stable compounds by achieving two valence electrons. Lithium, an alkali metal with three valence electrons, is also an exception to the octet rule. Lithium tends to lose one electron to take on the electron configuration of the nearest noble gas, helium, leaving it with two valence electrons.
- There are two ways in which atoms can satisfy the octet rule.
- One way is by sharing their valence electrons with other atoms.
- The second way is by transferring valence electrons from one atom to another.
- Atoms of metals tend to lose all of their valence electrons, which leaves them with an octet from the next lowest principal energy level.
Atoms of nonmetals tend to gain electrons in order to fill their outermost principal energy level with an octet. Watch the following video to learn how to use the octet rule to predict the charge of an ion.
Why is chlorine 2 8 7?
Electron Arrangement – Electrons are not randomly arranged in an atom and their position within the atom can be described using electron arrangements, which are a simplified version of electron configurations. For each element of interest, we look at the number of electrons in a single atom and then determine how those electrons are arranged based on the atomic model.
- The main idea behind electron arrangements is that electrons can only exist at certain energy levels.
- By understanding the energy levels of electrons in an atom, we can predict properties and understand behavior of the atom.
- As shown in the figure below, there are multiple energy levels where electrons can be found.
As the energy level increases, the energy difference between them decreases. A maximum of two electrons can be found in the \(n=1\) level; eight electrons can be in the \(n=2\) level. Although the \(n=3\) and \(n=4\) levels show only eight electrons in this diagram, those energy levels can hold more but not until we start looking at the transition metals. Figure \(\PageIndex \): Energy levels of electrons. Example \(\PageIndex \) What is the electron arrangement of oxygen? Solution Oxygen has eight electrons. The first two electrons will go in the \(n=1\) level. Two is the maximum number of electrons for the level so the other electrons will have to go in a higher energy level.
The \(n=2\) level can hold up to eight electrons so the remaining six electrons will go in the \(n=2\) level. The electron arrangement of oxygen is (2, 6). Example \(\PageIndex \) What is the electron arrangement of chlorine? Solution Chlorine has 17 electrons. The first two electrons will go in the \(n=1\) level.
Two is the maximum number of electrons for the level so the other electrons will have to go in higher energy levels. The \(n=2\) level can hold up to eight electrons so the next 8 electrons will go in the \(n=2\) level. The remaining 7 electrons can go in the \(n=3\) level since it holds a maximum of 8 electrons.
The electron arrangement of chlorine is (2, 8, 7). The electron arrangement also provides information about the number of valence electrons, The valence electrons are the electrons in the highest energy level and the ones involved in ion and bond formation. Knowing the number of valence electrons will allow us to predict how a particular element will interact with other elements.
Electrons in lower energy levels are called the core electrons, Let’s look at the figure below which shows the electron diagram for magnesium and its 12 electrons. The first two electrons are found in the \(n=1\) energy level, the next eight electrons are found in the \(n=2\) level, and the remaining two electrons are found in the \(n=3\) level. Figure \(\PageIndex \): Electron diagram for magnesium. The electron arrangement also shows the number of valence electrons which is two for magnesium because there are two electrons in the \(n=3\) energy level which is the highest occupied energy level for magnesium.
- This corresponds to the \(2+\) charge formed when magnesium forms an ion.
- It is willing to lose 2 electrons so that it has the same electron arrangements as the nearest noble gas, which is neon (2, 8).
- Atoms will gain or lose electrons to look like the nearest noble gas because the noble gases are unreactive due to the stability of having eight electrons in the highest energy level.
This desire of atoms to have eight electrons in their outermost shell is known as the octet rule, Example \(\PageIndex \) What is the electron arrangement of aluminum? How many valence electrons does it have? Solution Aluminum has 13 electrons so it will have the electron arrangement (2, 8, 3) which represents two electrons in the \(n=1\) energy level, eight electrons in the \(n=2\) level, and three electrons in the \(n=3\) level.
- Aluminum has three valence electrons (indicated by the three electrons in the \(n=3\) level).
- Example \(\PageIndex \) How many valence electrons does chlorine have? How many electrons will chlorine gain or lose to form an ion? Solution Chlorine has 7 electrons in its valence shell.
- To meet the octet rule, it must either gain one electron or lose seven electrons.
Gaining one is easier than losing seven so it will gain one electron to have a total of eight electrons when it forms an ion (i.e. charged particle).
Do all elements need 8 valence electrons?
While most atoms obey the duet and octet rules, there are some exceptions. For example, elements such as boron or beryllium often form compounds in which the central atom is surrounded by fewer than eight electrons (e.g., BF₃ or BeH₂).
Is chlorine 2 8 7?
The element chlorine (Cl) has an atomic number of 17. So, the electron arrangement of chlorine is 2, 8, 7.
Who has valency 7?
Valency of First 30 Elements
|Valency of Carbon||6||4|
|Valency of Nitrogen||7||3|
|Valency of Oxygen||8||2|
|Valency of Fluorine||9||1|
What is 7 in chlorine?
Properties – Chlorine, liquefied under a pressure of 7.4 bar at room temperature, displayed in a quartz ampule embedded in acrylic glass Solid chlorine at −150 °C Chlorine is the second halogen, being a nonmetal in group 17 of the periodic table. Its properties are thus similar to fluorine, bromine, and iodine, and are largely intermediate between those of the first two. Chlorine has the electron configuration 3s 2 3p 5, with the seven electrons in the third and outermost shell acting as its valence electrons,
Like all halogens, it is thus one electron short of a full octet, and is hence a strong oxidising agent, reacting with many elements in order to complete its outer shell. Corresponding to periodic trends, it is intermediate in electronegativity between fluorine and bromine (F: 3.98, Cl: 3.16, Br: 2.96, I: 2.66), and is less reactive than fluorine and more reactive than bromine.
It is also a weaker oxidising agent than fluorine, but a stronger one than bromine. Conversely, the chloride ion is a weaker reducing agent than bromide, but a stronger one than fluoride. It is intermediate in atomic radius between fluorine and bromine, and this leads to many of its atomic properties similarly continuing the trend from iodine to bromine upward, such as first ionisation energy, electron affinity, enthalpy of dissociation of the X 2 molecule (X = Cl, Br, I), ionic radius, and X–X bond length.
Fluorine is anomalous due to its small size.) All four stable halogens experience intermolecular van der Waals forces of attraction, and their strength increases together with the number of electrons among all homonuclear diatomic halogen molecules. Thus, the melting and boiling points of chlorine are intermediate between those of fluorine and bromine: chlorine melts at −101.0 °C and boils at −34.0 °C.
As a result of the increasing molecular weight of the halogens down the group, the density and heats of fusion and vaporisation of chlorine are again intermediate between those of bromine and fluorine, although all their heats of vaporisation are fairly low (leading to high volatility) thanks to their diatomic molecular structure.
The halogens darken in colour as the group is descended: thus, while fluorine is a pale yellow gas, chlorine is distinctly yellow-green. This trend occurs because the wavelengths of visible light absorbed by the halogens increase down the group. Specifically, the colour of a halogen, such as chlorine, results from the electron transition between the highest occupied antibonding π g molecular orbital and the lowest vacant antibonding σ u molecular orbital.
The colour fades at low temperatures, so that solid chlorine at −195 °C is almost colourless. Like solid bromine and iodine, solid chlorine crystallises in the orthorhombic crystal system, in a layered lattice of Cl 2 molecules. The Cl–Cl distance is 198 pm (close to the gaseous Cl–Cl distance of 199 pm) and the Cl···Cl distance between molecules is 332 pm within a layer and 382 pm between layers (compare the van der Waals radius of chlorine, 180 pm).
Why can chlorine form 7 bonds?
What is the maximum number of covalent bonds? Join Vedantu’s FREE Mastercalss Answer Verified Hint: Covalent compounds formed by sharing of electrons between their atoms. Covalent bonds form by the help of valence shell electrons. The covalent bond depends upon the number of valence shell electrons.
Complete answer: Note:
Covalent bond is formed when sharing of electrons takes place between two atoms. For the formation of covalent bonds, valence electrons are required. So, for the maximum number of covalent bonds, we have to check the maximum number of valence shell electrons.
- In noble gas there is a maximum number of valence electrons, i.e.
- Eight electrons.
- Which means it can form $8$ covalent bonds.
- But noble gases rarely form bonds; they are very inactive because they are stable and have electronegativity of almost zero.Metals in the group second can form many covalent bonds such as copper that have the possibility of forming \ covalent bonds as it contains \ valence electrons, i.e.
$2\;4s$ and $9\;3d$, But we all know that metals tend to form ionic bonds not covalent bonds.After these two group elements, halogen has a maximum number of valence electrons. It has seven valence electrons. Thus, it can make seven covalent bonds. For example, $ClO_4^ $ have seven covalent bonds.
Chlorine in $ClO_4^ $ has seven covalent bonds that share electrons with four oxygen atoms. Out of four, three oxygen atoms form double bonds with chlorine whereas one oxygen atom forms a single bond with chlorine atom. Thus the maximum number of covalent bonds is seven. Due to the sharing of electrons, the covalent bond is the strongest bond.
It breaks with the help of enzymes. Covalent bonds form between two atoms when one of them cannot easily have a noble gas configuration even through gaining or losing electrons. : What is the maximum number of covalent bonds?
Why is chlorine in group 7?
Easy exam revision notes for GSCE Chemistry The Group 7 elements are placed in the vertical column, second from the right-hand side of the periodic table. All Group 7 elements have 7 electrons in their outer shell. Fluorine, chlorine, bromine, iodine, and astatine, all belong to Group 7.
Why is chlorine in group 7 of the periodic table?
Group 7 (Halogens) (GCSE) — the science hive The halogens are found in group 7 of the Periodic Table and are one electron away from a full outer shell of electrons. The halogens include the elements chlorine, bromine and iodine which all behave in similar ways due to similarities in their electron configurations. As you go down the halogens, from fluorine to astatine, the elements become darker in colour and have a higher boiling point. Boiling point increases as you go down the group because the mass of each element increases and they have more electrons around their nuclei.
Fluorine is a pale yellow gas Chlorine is a poisonous green gas Bromine is a toxic red-brown liquid Iodine is a dark grey solid which gives off a purple vapour when heated Astatine is a black solid
Unlike the group 1 metals, reactivity decreases as you go down the halogens. This means that fluorine, at the top of the group, is the most reactive. Fluorine is so eager to react with anything that it is almost never found as a pure element and it is so dangerous to work with that scientists avoid handling it in reactivity experiments.
Chlorine is less reactive and much more manageable, and added to water in small quantities to kill microorganisms to make it safe to drink. The group 7 elements want to gain one more electron so that they have a stable electronic structure. The smaller the atom, the easier it is to grab an electron from another atom, making the atom more reactive,
As you go down group 7, the atomic radius increases and it becomes more difficult to attract another electron. In displacement reactions, a more reactive element will displace (replace) a less reactive one. Think of it as the introduction of an attractive geordie on love island, forcing someone else out of a relationship and leaving them by themselves. Displacement reactions involving halogens and halogen ions ( halides ) can be used to provide evidence for the order of reactivity of the halogens. Let’s say we add iodine to a solution of potassium bromide. This time we’re adding an element which is less reactive than the halogen in the compound so no reaction will take place. : Group 7 (Halogens) (GCSE) — the science hive