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Increase in ozone levels in the stratosphere over Antarctica, are the result of complex chemical processes. The return of the Sun at the end of winter triggers photochemical reactions that lead to the destruction of ozone in the stratosphere. As reported Over the Arctic the gradual development of an...
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Please use UP and DOWN arrow keys to review autocomplete results. The first COVID-19 vaccines have been authorized for use and dissemination has begun in several countries, marking a major turning point in the pandemic and bringing fresh optimism for a next normal in the new year.
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Dec 08, 2013 · "Here you've got the noble gases and the halogens. A gas is never going to be much good as a currency. ... The melting point of platinum is 1,768C. ... and therefore an enormous increase in the ...
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That's why in addition to R, scientists use a value called the dispersion factor (k), which describes how much a disease clusters. The lower k is, the Why coronaviruses cluster so much more than other pathogens is "a really interesting open scientific question," says Christophe Fraser of the University of...
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Sep 30, 2013 · Melting and Boiling Points: The melting and boiling points of very low compared to the other elements on the periodic table. Even though they are quite low, the melting and boiling points increase as you go down the list. Noble gases have very low densities, the gases melt and boil extremely fast because of their element’s physical
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Dec 22, 2020 · Trend of change down the group. The melting and boiling points of noble gases increase when going down Group 18. Explanation: This is because the atomic sizes of the noble gases increase when going down the group from helium to radon, thus the van der Waals forces of attraction between the atoms become stronger. Hence, more heat energy is ...
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4. How does the tendency to lose electrons will change in a group and why? 5. Justify the statement –Atomic size of an element decreases along a period whereas increasing down the group. 6. Why metallic oxides are basic in nature whereas Non-metallic oxides are acidic in nature.
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A Search for Quasi-periodic Oscillations in the Blazar 1ES 1959+650. SciTech Connect. Li, Xiao-Pan; Luo, Yu-Hui; Yang, Hai-Yan. We have searched quasi-periodic oscillations (QPOs) in the 15 GHz light curve of the BL Lac object 1ES 1959+650 monitored by the Owens Valley Radio Observatory 40 m telescope during the period from 2008 January to 2016 February, using the Lomb–Scargle Periodogram ...
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A company increases capacity by spending money to find and develop reserves and to increase the Why cannot fields produce at a surge capacity for long periods? What does the maximum In it, crude oil and other inputs such as natural gas condensates are heated to the point of boiling at the...
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Oct 06, 2018 · *You are NOT required to know the specifics of why transition elements have multiple valencies (or oxidation states) whereas other elements do not . Group 0 – Noble gases . Noble gases are unreactive; they have a valency of 0. Their outer electron shell is already complete. Noble gases have various uses: Helium is used in balloons.

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For example, the atomic size tends to increase as you move down a group and decrease as you move across a period. As you move down a group, the number of energy levels increases, so there are more “clouds” around the nucleus. As you move across a period, the energy level remains constant, but the number of protons (atomic number) is increasing. Sep 09, 2015 · Noble Gases Neon and the elements below it in Group 18 have eight electrons in their outer energy levels. ... Unlike halogens, the reactivities of alkali metals increase down the group. Buy or sell new and used items easily on Facebook Marketplace, locally or from businesses. Find great deals on new items shipped from stores to your door.


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The noble gases are the chemical elements in group 18 of the periodic table. They are the most stable due to having the maximum number of valence electrons their outer shell can hold. Therefore ...

  1. 3. Take down notes and record points for clarification. 4. Always aim to get at least 70% of the total number of items given. 2. The addition of a solute will increase the boiling point of the solution. _ 3. The van't Hoff factor is only applicable for non-electrolyte solutions. _
  2. 3) Also, do the abbreviated orbital box diagram for the element. 2 in s and 5 in p. G. Inert gases (noble gases): Label the noble gases on your periodic table and color them. 18th column. 1) Why are they “happy”? Octet rule is satisfied since they have completely filled valence orbitals. (2 in s and 6 in p) Apr 07, 2016 · So, when the atomic number increases, the mass number of the isotopes is higher (though they are different isotopes), and so the relative atomic mass will increase. Since this occurs as you go down a group, the atomic mass increases as you go down a group. When we compare the noble gas relative atomic masses M r, we get: M r,He = 4.0026
  3. Then, at the boiling point, the temperature remains steady until the water is completely vapourised and behaves as a gas. It appears to boil at the top, but lower down the porridge does not reach boiling point. This increases the boiling point of the liquid, allowing it to be stored for extended periods.
  4. Melting and boiling points generally increase going down the group. This is a plot of ionization potential versus atomic number. The noble gases, which are labeled, have the largest ionization potential for each period. Water Boiling Points at Higher Pressure - Online calculator, figures and tables showing boiling points of water at pressures ranging from 14.7 to 3200 psia (1 to 220 bara). Temperature given as °C, °F, K and °R.
  5. 32. Police ….. that a terrorist group might be behind the kidnapping. suppose fancy suspect accuse. 33. When Christopher smiles, he ….. me of his grandfather. remembers recall rethinks reminds. 47. Just put this powder down and it should ….. any more ants from getting in. prevent avoid refuse forbid.
  6. This process is called gas exchange and is essential to life. In addition to the lungs, your respiratory system includes the trachea (windpipe), muscles of the chest wall and diaphragm, blood vessels, and tissues that make breathing and gas exchange possible.Increase frustration among common people: State of extreme poverty can cause frustration among poorer citizens when most of their dreams remain unfulfilled. Increases crime rates and addiction: When poverty restricts people from life's benefits, people may resort to crime and addiction.This happens because as you go down a group, it is easier for electrons to be taken or given away, resulting in high Chemical Reactivity. And you go from left to right on the periodic table elements have more electrons in their valence shells they have to get rid off which requires an element to have high energies which results into lower Chemical Reactivity.
  7. In a very small atom like helium, the dipoles formed are tiny. The atoms won't start to stick together to form a liquid until you get a temperature close to absolute zero. As you go down the group, the atoms get bigger, and the temporary fluctuating dipoles increase. So the boiling points increase.
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  9. Increasing the pressure leads to water depositing straight from gas to solid. It does not pass through the liquid form or the triple point as the temperature and gas. Temperature (not to scale). In terms of the relative entropies of all relevant species, explain why the boiling point of salt water is higher than...Uses of Noble Gases. Due to unreactive nature, low density and non-flammability of noble gases, they have a variety of uses listed below: Helium. The low density of helium is made use of in filling airships and balloons. Helium is much less dense than air (lighter) and used in filling weather balloons, airships and decorative balloons.
  10. Noble Gases. Inert. unreactive. full outer shell; do not gain or lose electrons; can be used in light bulbs. will not react with the hot metal filament; Monatomic. exist as single atoms; unreactive; Low Boiling Point. boiling points do not increase down the table; RAM increases down the table; Low Density. low density; increase down the table ... What explains the higher boiling point of hydrogen fluoride? A The bond energy of HF molecules is greater C The electronegativity of fluorine is much higher than for other elements in the group. B increased temperature due to global warming C increased ultraviolet radiation as the ozone layer is...5The population of Asia is expected to increase from 4.6 billion in 2020 to 5.3 billion in 2055, then start to decline. Meanwhile, roughly a third of the world's babies are projected to be born in Asia by the end of this century, down from about half today and from a peak of 65% in the 1965-70 period.
  11. Explain why the noble gases are inert. ... As you go down the group melting point increases. ... boiling points increase with chain length, ...
  12. Pnictogen Group – Group 15. Increase in metallic character as you go down the group. Nitrogen is a colorless, odorless gas. Phosphorus can be found as a white, red, or black solid. Arsenic is a shiny gray solid that is brittle. Antimony is a shiny silver gray solid that is very brittle. Bismuth is a shiny gray solid that has pink cast to it. May 03, 2020 · On moving down the group metallic character increases. Carbon is strictly non-metallic, silicon is non-metal , germanium is a metalloid where tin and lead are soft metal with low melting point. Melting and boiling point . The melting and boiling point of group 14 elements are much higher than those of corresponding elements of group 13.

 

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increase as you go across a row –Notice that the top three noble gases do not have an electronegativity –In the early 1960s, it was determined that highly electronegative fluorine could react with krypton to make a stable compound •Top to bottom –electronegativity generally decreases as you go down a group Then, at the boiling point, the temperature remains steady until the water is completely vapourised and behaves as a gas. It appears to boil at the top, but lower down the porridge does not reach boiling point. This increases the boiling point of the liquid, allowing it to be stored for extended periods.The melting and boiling points increase down the group because of thevan der Waals forces. The size of the molecules increases down the group. This increase in size means an increase in the... Noble Gases have a very stable electron configuration, therefore, they have the highest amount of ionization energy within their periods. It decreases down a family because electrons farther from the nucleus are easier to remove. Ionization Energy levels of Noble Gases group in Descending Order :: He, Ne, Ar, Kr, Xe, Rn Private transport is one of the world's biggest sources of greenhouse gases, with emissions rising year on year. It means the way you travel to work matters In our car dominated cities, can we cut down the carbon footprint of our daily commute? For many people, the journey to and from work are the...» Question 7 9 pts Provide an appropriate response to each statement a) The boiling points of noble gases increase down the group due to an increase in Select b) in decreasing order of intermolecular forces: London dispersion > hydrogen bonding dipole-dipole. decreasing melting point and boiling point. ... The reactivity of Group 17 elements gradually decreases when going down Group 17. This is due to. ... noble gases ... 2. Two groups thought they would be asked to give a presentation of a stuck pipe incident. 3. The members of our delegation thought to test a new rig. Exercise 5.Read the text, try to focus on its essential facts and choose the most suitable heading given below for each paragraph.

Oct 28, 2010 · - noble gases have the lowest melting points - starting from the left and moving right, melting point increases (until the middle of the table, it then starts to decrease) -an exception to this rule is Carbon.

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Oct 05, 2013 · Nonmetals have low melting and boiling points.Nonmetals low densities, because most of the elements are gases and liquids. Which is why the nonmetals will melt and boil faster.For example, Iodine, Phosphorus, and Sulfur have melting points of 44, 115, and 114 degrees Celsius, and boiling points of 280, 445, and 184 degrees. Why are H & He sometimes separated from Periodic Table? Hydrogen has one valence electron so it is normally placed in group 1. Hydrogen has a second home at the top of group 17 because it can gain an electron as the halogens do. Helium has two valence electrons like group 2 but is clearly a noble gas because its outer energy level is full. The noble gases are all colorless, odorless, and tasteless. They exist as monatomic gases, which means that their molecules consist of a single atom apiece. The boiling points of the noble gases increase in moving down the periodic table. Helium has the lowest boiling point of any element. It boils at 4.215 K (− 268.93 ° C).

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In group 16 tendencies to show -2 oxidation state decreases on going down the group. Q. 37. In group 16 +4 oxidation state become more stable than +6 oxidation state on going down the group. Gas demand is less exposed to the immediate effects of the current crisis than oil demand because of its relatively limited use for transport. With consumers constrained in their ability to respond to lower prices, adjustment in the gas market may also need to come in the form of halting some gas supply.

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Oct 16, 2018 · Each element in the periodic table has different characteristics from the rest unless they belong to the same family. The quiz below is designed to test out your understanding of the different elements found in the table. Give it a shot and look out for more quizzes like this. All the best! That is why, "[w]hen working from home, prioritizing your mindset and well-being at the start of the day is essential," Diggory told us. One helpful way to set boundaries so that a person does not become overwhelmed with competing tasks is to create a physical space that is for work only...Why are the words divided into two groups - those in normal text and those in bold? Pollution Recycling. 97% of scientists agree that climate change is happening and the main cause is from an increase in greenhouse gases (like carbon dioxide, methane and Nitrous Oxide) in the atmosphere.Mar 20, 2015 · Ans: • Because the outermost shell occupied with electron are full / achieve the duplet or octet electron arrangement. • So, noble gas does not donate, receive or share electron with other elements. 12. Going down Group 18 Size of atom increase • Going down Group 18 elements, the numbers of shells occupied with electron in the atom ... Cohesion also contributes to water's high boiling point, which helps animals regulate body temperature. Water is directly involved in many chemical reactions to build and break down important components of the cell. I Want to add U in group Please response.The boiling points increase down the group because of the the size of the molecules increases down the group. This increase in size means an increase in the strength of the van der Waals forces. We can already see a sharp increase in absenteeism in countries in lockdown. The "red" part of the population has increased by 10 percentage points to fully 25% of the population. In general, we know at-risk groups for long-term mental health issues will be the healthcare workers who are on the...All the noble or inert gases have 8 electrons in their valence shell except helium which has two electrons in its valence shell. Question 15(b) Name an element of group 18 which can form compounds. All group 1 metals have one electron in its outer shell. As we go down the group, the atom gets bigger. The bigger the atom, the further away the last electron. Therefore, the attraction between the nucleus and the last electron gets weaker. This makes it easier for the atom to give up the electron which increases its reactivity.

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The reactivity of Group 7 elements decreases down the group. Non-metal atoms gain electrons when they react with metals. Non-metal atoms gain electrons when they react with metals. When a halogen atom reacts, it gains one electron into their highest occupied energy level (outer shell) to form a singly negative charged ion. Jun 16, 2020 · Why does electron affinity decrease down a group? The less valence electrons an atom has, the least likely it will gain electrons . Electron affinity decreases down the groups and from right to left across the periods on the periodic table because the electrons are placed in a higher energy level far from the nucleus, thus a decrease from its pull. 2. The _____ achieve the electron configurations of noble gases by losing two electrons. 3. The _____ achieve the electron configuration of noble gases by gaining one electron. 4. The _____ have full s and p orbitals in the highest occupied energy levels. 5. Jun 19, 2018 · All cryogenic gases have very low boiling points (-150’ C), and hence need to be kept very cold. Possibly the most significant feature of cryogenic gases is the ability for small amounts of the gas to expand rapidly into extreme volumes of gas. Examples can include liquid nitrogen, liquid helium, and argon. Non-Liquified Compressed Gases

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halogen means any of the chemical elements fluorine, bromine,iodine,and astatine.The halogens or halogen elements are a series of nonmetal elements from Group 17 of the periodic table, made up by fluorine(F), chlorine(Cl), bromine(Br), iodine(I), and astatine(At). The undiscovered element 117, temporarily named ununseptium, may also be a halogen. Like all other groups in the periodic table ... The development of fertilizers has further increased the efficiency of agriculture, most of which are the fruits of the labors of chemical engineers. With a likely increase in the use of more and more advanced equipment in the future, it is an inevitability that engineers will become ever more important...Travel can also be cheaper and more rewarding when you speak the language of the country you're visiting. You won't be limited to staying in expensive foreigner hotels, eating at restaurants where the staff speaks English or traveling with a tour group.Halogens: The 7th group of the periodic table, are a family of toxic, coloured gases, with 7 valence electrons in it's outer shell. They decrease in reactivity going down the group. Physical features: Coloured, have a bitter taste, and terrible smell, there is a trend in state, in which halogens start from being gases then liquid to being solids. Other trends: Melting point and boiling point decreases down the group. Group II - the alkaline earth metals Magnesium, Calcium and Strontium all belong to Group 2. All Group 2 elements have two outer electrons, therefore they wish to lose two when bonding to create compounds. Certain atmospheric gases work as a kind of blanket, keeping the Earth warm. The amount of these 'greenhouse' gases used to be more or less the same for centuries. But the industrial revolution broke this balance.The boiling point of a substance is the temperature at which the substance boils, or enters a state of rapid evaporation. For pure water this is 100° Celsius or 212° Fahrenheit. This is measured at one atmosphere, that is, the air pressure at sea level. Boiling points can be changed in several ways.Why are Group 1 metals more reactive as you go down but Halogens are the opposite? I need help plz GCSE C1 CHEMISTRY AQA UNOFFICIAL MARK SCHEME 18th MAY 2017 Have the noble gases got the highest 1st, 2nd and 3rd ionisation energies in a perio URGENT HELP NEEDED!!!!!

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This process is called gas exchange and is essential to life. In addition to the lungs, your respiratory system includes the trachea (windpipe), muscles of the chest wall and diaphragm, blood vessels, and tissues that make breathing and gas exchange possible.Why did Russia allow oil prices to drop? Would the fall even have been avoidable? The primary cause of the current collapse in oil prices is the novel coronavirus outbreak. In the meantime, economists expect nosediving oil prices to cost Russia about 0.5 percentage points of economic growth.Neglecting relativity leads to an almost fourfold increase of the cohesive energy, and in turn to an increase of the melting and boiling points by 300 K and 700 K. Hence, the liquid aggregate state as well as the weakly interacting nature of Cn are both due to relativistic effects or, in other words, Cn is a relativistic noble liquid. Why am I losing points when answering questions correctly? Why does the potions area keep repeating weigh lion fish spines? It doesn't seem .. What does increases your attributes mean? How many classes will you have to take to play quidditch?

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Explain why the noble gases are inert. ... As you go down the group melting point increases. ... boiling points increase with chain length, ... You might wonder why this is part of the research process. Watching movies, reading books, and writing various stuff hone your comprehension and ability to analyze. These can improve your vocabulary and aid you in finding your voice as a researcher.May 04, 2015 · Ch. 10 - Explain why liquids assume the shape of any... Ch. 10 - What is the evidence that all neutral atoms and... Ch. 10 - Open the PhET States of Matter Simulation... Ch. 10 - Define the following and give an example of each:... Ch. 10 - The types of intermolecular forces in a substance... Ch. 10 - Why do the boiling points of the noble gases... The melting and boiling points increase down the group because of the van der Waals force. The size of the molecules increases down the group. This increase in size means an increase in the strength of the van der Waals forces. F < Cl < Br < I < At Account for the following: i)Fluorine does no show variable oxidation states while other members of the halogen family exhibit variable oxidation states. ii)Iodine is ... This attraction is caused by the correlated motion of electrons. With increasing amount of electrons, there can be more correlated motion and hence there is a stronger interaction between the molecules and an increasing melting / boiling point when you go down in group 7. When does water boil? Boiling occurs when bubbles form within a liquid, marking a change from a substance's liquid or solid phase into a gas. Witness an experiment explaining why fresh water and seawater have different freezing points.2.1.6 Reactivity decreases down the group 2.1.6.1 A more reactive halogenw ill displace a less reactive halogen in a displacement reaction 2.1.6.2 According to the octet rule, halogens gain one electron when they react

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The noble gases were all isolated for the first time within a period of only five years at the end of the 19th century. Their very existence was not suspected until the 18th century, when early work on the composition of air suggested that it contained small amounts of gases in addition to oxygen, nitrogen, carbon dioxide, and water vapor. Dec 22, 2020 · Trend of change down the group. The melting and boiling points of noble gases increase when going down Group 18. Explanation: This is because the atomic sizes of the noble gases increase when going down the group from helium to radon, thus the van der Waals forces of attraction between the atoms become stronger. Hence, more heat energy is ... The development of fertilizers has further increased the efficiency of agriculture, most of which are the fruits of the labors of chemical engineers. With a likely increase in the use of more and more advanced equipment in the future, it is an inevitability that engineers will become ever more important...Click hereto get an answer to your question The boiling points of noble gases increases...Therefore, when looking at the noble gases, the boiling point is predicted to increase as you go down, in the order He, Ne, Ar...Atomic and Physical Properties of Elements of Group 16, 17, and 18.May 09, 2017 · - Reactivity, density and softness increase further down the group - Melting point and boiling points decrease down the group – metallic bond becomes weaker - Reactivity increases – more electron shells attraction between the nucleus and the valence electron becomes weaker the electron loses more easily Group 7: Halogen

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49. Why did you buy flour? a) I'm going to make a few cakes. e. selling the company's products. 131. Match the right verb with the group of nouns 'a problem, an enquiry, a customer'. e. arrange. 132. Match the right verb with the group of nouns 'a letter, a fax, a copy'.Group 6A elements are reduced when in contact with metals to form -2 anions React with hydrogen gas to form H 2 X gases (except oxygen which makes water) Are oxidized with oxygen gas to form dioxides Halogens: Melting points and boiling points increase down the group unlike alkali metals Fluorine and chlorine gas are pale, yellow gases Levels of greenhouse gases have gone up and down over the Earth's history, but they Now, humans have increased the amount of carbon dioxide in the atmosphere by more than a third since the Why does this matter? The rapid rise in greenhouse gases is a problem because it's changing the climate...

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Oct 21, 2008 · Why do the noble gases increase in reactivity as you go down the family? He is unreactive, Neon is unreactive, Argon is unreactive, Krypton forms some compounds like krypton fluorides and Xenon can form XePtF6 (as discovered by Neil Barlett).. Neon, chemical element, inert gas of Group 18 (noble gases) of the periodic table, used in electric signs and fluorescent lamps. Colorless, odorless, tasteless, and lighter than air, neon gas occurs in minute quantities in Earth’s atmosphere and trapped within the rocks of Earth’s crust.

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plastic, aluminium and clothing recycling banks and take turns to take everything to a local recycling point. In this way, your community will be helping to save limited raw materials.Examples of intensive properties are: density, solubility, reactivity, and melting/boiling points 3. Circle the extensive properties and underline the intensive properties. A. The mass of the unknown solid is 15g B. The melting point of ice is 00C C. The density of Calcium chloride is 2.15 g/cm3 D. Sodium chloride is soluble in water E. Certain atmospheric gases work as a kind of blanket, keeping the Earth warm. The amount of these 'greenhouse' gases used to be more or less the same for centuries. But the industrial revolution broke this balance.

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May 09, 2017 · - Reactivity, density and softness increase further down the group - Melting point and boiling points decrease down the group – metallic bond becomes weaker - Reactivity increases – more electron shells attraction between the nucleus and the valence electron becomes weaker the electron loses more easily Group 7: Halogen 2. The _____ achieve the electron configurations of noble gases by losing two electrons. 3. The _____ achieve the electron configuration of noble gases by gaining one electron. 4. The _____ have full s and p orbitals in the highest occupied energy levels. 5. The enthalpy of vaporization increases down the group as the polarizability of the atoms increases. Physical Properties of the Noble Gases. Because the inter-atomic forces are very weak, the melting points and boiling points are also very low. The boiling point He is the lowest of any element, only four degrees above absolute zero. Feb 13, 2020 · The Noble Gases by Adam Furgang. Rosen Group, 2010. A simple 48-page guide to helium, neon, argon, krypton, xenon, and radon for ages 9–12. Noble Gases by Jens Thomas. Benchmark Books, 2002. A shorter book describing the properties of noble gases, how they're prepared, and how they're used in lighting, medicine, and elsewhere. Articles As you go down the group, Boiling point increases. Because the atomic radii increases down a group and the london forces between the atoms Intermolecular Forces Explain why Ethane is a gas at room temperature while Hexane is a liquid. • The greater the surface area available for contact, the...They have generally high melting and boiling points. They have generally low melting and boiling points. Metallic character increase as we go down the group. Non metallic character increase as we move form left to right along the period. Q. 10.Define atomic radius of an element. How does it vary along the period and group? Ans. In Group 7, the further down the group an element is the higher its relative molecular mass, melting point and boiling point. In Group 7, the reactivity of the elements decreases going down the group. To react they need to gain 1 electron A more reactive halogen can displace a less reactive halogen from an aqueous solution of its salt. The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor. The boiling point of a liquid varies depending upon the surrounding environmental pressure.The melting and boiling points increase down the group because of the van der Waals force. The size of the molecules increases down the group. This increase in size means an increase in the strength of the van der Waals forces. F < Cl < Br < I < At "During any chemical reaction, the atoms of all the elements tend to gain stability by acquiring an electronic configuration of the nearest noble gas element." Thus, during chemical reactions atoms of all elements tend to achieve eight electrons in their outermost shell. This is known as the octet rule.