11 amu-2 charge . Mass Number = # of Protons + # of Neutrons bromineThe neutral atom of bromine has 35 electrons because the number of electrons equals the number of protons. Therefore, the number of electrons in neutral atom of Selenium is 34. electrons To view the purposes they believe they have legitimate interest for, or to object to this data processing use the vendor list link below. A neutral atom has the same number of protons and electrons (charges cancel each other out). Analysis of ultrasonic effect on powder and application to radioactive sample compaction. The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a, b and c). SchoolMyKids.com is part of the ParentsNKids Network. If there are too many or too few neutrons for a given number of protons, the resulting nucleus is not stable and it undergoesradioactive decay. Proton is a positively charged particle. The number of electrons and protons in an atom is the same but the number of neutrons is different. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. Let's try an example: We can choose selenium, which has an atomic number of 34, meaning there are 34 total electrons in a neutral atom of selenium. Theconfiguration of these electronsfollows from the principles of quantum mechanics. Selenium is a Other Nonmetal element. The consent submitted will only be used for data processing originating from this website. Protons and neutrons are in the center of the atom, making up the nucleus. Refer to table below for the Electrical properties ofSelenium, Refer to table below for Thermal properties of Selenium. Copyright 2023 Periodic Table | All Rights Reserved |, The chief commercial uses for selenium today are, Germanium Protons Neutrons Electrons Electron Configuration, Bromine Protons Neutrons Electrons Electron Configuration. 25 - 11 = # of Neutrons. See how this Interactive Periodic Table helps you, (For Interactive Periodic table, view on laptop/desktop for better experience. We and our partners use cookies to Store and/or access information on a device. Seleniumis a chemical element with atomic number34which means there are 34 protons in its nucleus. A gas occupies a volume of 2.4 L at 14.1 kPa. Electrons, protons, and neutrons are located in the atom as permanent particles. That is, the mass of a proton is approximately 1837 times greater than the mass of an electron. What is the difference between the number of electrons in an atom of Selenium (Se) which has an atomic number of 34, and the number of electrons in an atom of Aluminum (Al) . The atom is overall charge neutral. Feel free to ask a question, leave feedback or take a look at one of our articles. Nanomaterials (Basel). Therefore, the total number of protons and neutrons is called the atomic mass number. An ion has an unequal number of protons and electrons. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10-19 coulombs. Selenium is the 34 element on the periodic table. What is its mass? The properties of the elements and their compounds depend on theelectron configuration. Therefore, this particular atom of tungsten contains 112 neutrons. Save my name, email, and website in this browser for the next time I comment. Therefore, a selenium atom has thirty-four protons and thirty-four electrons. Mass Number = # of Protons + # of Neutrons The true mass of an atom is an incredibly small quantity. 1s 2s22p1 a) 2 b) 3 C) 5 d) 7. In the periodic table, the elements are listed in order of increasing atomic number Z. Electron configuration ofSeleniumis[Ar] 3d104s24p4. Therefore, atomic mass refers to the total mass of protons and neutrons. Therefore, scientists utilize three different elemental symbolismstoreferto specificelemental isotopes. The neutron has a mean square radius of about 0.81015 m, or 0.8 fm, and it is a spin- fermion. What are the atomic number, mass number and symbol of the chlorine isotope with 18 neutrons? Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The number of neutrons. An atomic number is a number that carries the properties of an element. Im Farhan Sadik. It hasa positive electric charge (+1e)and a rest mass equal to 1.67262 1027kg (938.272 MeV/c2) marginally lighter than that of the neutron but nearly 1836 times greater than that of the electron. final answer: It must be noted, atoms lack a well-defined outer boundary. How many protons, neutrons and electrons does beryllium have? In an atomic ion only the number of electrons changes but the number of protons and neutrons does not change. how many protons neutrons and electrons does Ison have, How many protons , neutrons , and electrons does the element mass number (number of protons and neutrons) to get number of neutrons. Why is it important for us to know the number of electrons and protons? What is the charge of the atom's nucleus? The atomic radius ofSeleniumatom is120pm(covalent radius). . 60 - 27 = # of Neutrons, Mass Number = # of Protons + # of Neutrons The number of electrons in an electrically-neutral atom is the same as the number of protons in the nucleus. For a neutral atom, the number of electrons can be found by knowing the atomic number of that atom. 82Se is decaying by double beta decay with a half-life of 1.081020years. 8 electrons; while chlorine (CI) exists in two forms, one of which has 17 -protons and 18 neutrons, the other 17 protons and 20 neutrons in the . How many protons neutrons and electrons does selenium 30? Log in for more information. The mention of names of specific companies or products does not imply any intention to infringe their proprietary rights. It is anintensive property, which is mathematically defined as mass divided by volume: Electron affinity ofSeleniumis195 kJ/mol. where X is any atom or molecule capable of being ionized, X+is that atom or molecule with an electron removed (positive ion), and eis the removed electron. 1). What volume will the gas . 35 protons, 45 neutrons, and 36 electrons \ b. Since the number of electrons and their arrangement are responsible for the chemical behavior of atoms, theatomic numberidentifies the various chemical elements. Your email address will not be published. Required fields are marked *. Thechemical properties of the atomare determined by the number of protons, in fact, by number andarrangement of electrons. 1) You may use almost everything for non-commercial and educational use. How many shells does selenium have? However, scientific research has revealed that the particles that make up atoms are formed by smaller particles, subatomic particles. How many neutrons does it have? It's 4. Selenium-78 is composed of 34 protons, 44 neutrons, and 34 electrons. And to arrange the electrons, you must know the number of electrons in that element. It hasno electric chargeand a rest mass equal to 1.67493 1027 kgmarginally greater than that of the proton but nearly 1839 times greater than that of the electron. Outside the nucleus, negatively charged. We represent this selenide ion as Se2 . We and our partners use data for Personalised ads and content, ad and content measurement, audience insights and product development. Density of Selenium Density of Selenium is 4.819g/cm3. A. Multiple-choice. He called that number the order of the atoms. The charge on the proton and electron are exactly the same size but opposite. number) 600. Hence, it lies in group 16. 4. Finally, recall that every atom of a certain element must have a definednumber of protons and electrons. 18 protons and electrons and 22 neutrons. Each electron is influenced by the electric fields produced by the positive nuclear charge and the other (Z 1) negative electrons in the atom. Take the difference of the mass number and the atomic number to get the number of neutrons. This fact has key implications for the building up of the periodic table of elements. That is, the atomic number is the total number of protons. 18) What is the mass number of an atom that contains 30 protons, 30 electrons, and 35 neutrons? Electrons surround the nucleus. Chlorine-18 mass number=17+18= then Se has a mass of 79 so to get the neutrons we minus the Thus, the number of positive charges present in the nucleus of an element is called the atomic number of that element. These individual "versions" of an element are called isotopes, which are defined as atoms of an element that have the same atomic numbersand, therefore, contain the same number of protons, butdifferent mass numbers, and, therefore, contain differingnumbers of neutrons. Selenium-82 is composed of 34 protons, 48 neutrons, and 34 electrons. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Your email address will not be published. 35. Atomic mass (A) = Nucleus mass = Total mass of protons and neutrons (p + n), Again, the mass of each proton and neutron is about 1amu. While a minimum amount of glue is required to adhere one object to another, a small amount of excess glue will not prevent those objects from sticking together, but a large excess of glue could prove to be problematic. NASA Astrophysics Data System (ADS) Kim, Jungsoon; Sim, Minseop; Kim, Jihyang; Kim, Moojo A neutral iron atom contains 26 protons and 30 neutrons plus 26 electrons in four different shells around the nucleus. This number is equal to the serial number of the periodic table. [Xe] 6s2 for barium). Mass Number = # of Protons + # of Neutrons. Which is greater 36 yards 2 feet and 114 feet 2 inch? It rarely occurs in its elemental state in nature, or as pure ore compounds. In which set do all the species contain more electrons than neutrons? 2) You may not distribute or commercially exploit the content, especially on another website. Whena hydrogen atomremoves an electron from its orbit, the positively charged particle that remains is called a proton. The chemical symbol for Selenium is Se . Number of Protons: 34: Number of Neutrons: 45: Number of Electrons: 34: Melting Point: 217.0 C: Boiling Point: 684.9 C: Density: 4.79 grams per cubic centimeter: Normal Phase: Solid: Family: Nonmetals: Period: 4: . Mass numbers of typical isotopes of Seleniumare74; 76; 77; 78; 80. Protons A proton is another one of three main particles that make up the atom. Since selenium is the 34th element of the periodic table, the atomic number of selenium is 34. What is the charge of the atom's nucleus? The English chemist Frederick Sodi first came up with the idea of isotopes in 1912, and the scientist Aston in 1919 identified two different massneon atoms(20Ne,22Ne). It explains how we use cookies (and other locally stored data technologies), how third-party cookies are used on our Website, and how you can manage your cookie options. Neutrons: 45 and the angles between them Lattice Angles (alpha, beta and gamma). 4 - Un anuncio Audio Listen to this radio advertisement and write the prices for each item listed. Mass numbers of typical isotopes ofSeleniumare74; 76; 77; 78; 80. A protonis one of thesubatomic particlesthat make up matter. Electrons are the permanent core particles of an atom. This is important as it is the Valence electrons 4s2 4p4, electrons in the outermost shell that determine the chemical properties of the element. 4 protons, 4 electrons, and 5 neutrons b. All others are under a minute, most under a second. The total number ofneutronsin the nucleus of an atom is called theneutronnumberof the atom and is given thesymbol N. Neutronnumber plusatomic numberequals atomic mass number:N+Z=A. Find step-by-step Chemistry solutions and your answer to the following textbook question: Identify each of the following atoms or ions: a. Most elements have more than one possible oxidation state. 1.2 Electron Configuration It is located in group 16 and period 4 in the modern periodic table. A Selenium atom, for example, requires the following ionization energy to remove the outermost electron. The mass of the neutron is 1.674 1027kg. Selenium has 30 isotopes. Isotope Abundance Nuclear Symbol Mass number =number of protons + number of neutrons. Since the mass of an electron is 1/2,000thof the mass of a proton, any contribution that electrons make to the overall mass of an atom is negligible. We realize that the basics in the materials science can help people to understand many common problems. . View ENE8210-AUT2022-Chap-III-nergie Nuclaire (2).pdf from ELEC 123 at Polytechnic School of Algiers. What is it's mass number? 186 = 74 + # of Neutrons Symbol of Selenium is Se. Three isotopes of hydrogen are modeled in Figure \(\PageIndex{1}\). Its actual charge is +1.602 1019coulombs. Each electron is influenced by the electric fields produced by the positive nuclear charge and the other (Z 1) negative electrons in the atom. What does the number at the top of the box tell you about the atom? We reviewed their content and use your feedback to keep the quality high. Therefore, the mass of the nucleus is called atomic mass. 40 - 19 = # of Neutrons. Often, the resulting number contains a decimal. Which is the electron configuration of a chromium atom in the ground state? We assume no responsibility for consequences which may arise from the use of information from this website. 2003-2023 Chegg Inc. All rights reserved. Electrons revolve around the nucleus in a specific orbit. The ionic properties of the elements depend on the exchange of electrons. a) 2 b) 6 c) 10 d) 14 Al 21) lons can be formed from atoms by losing or gaining electrons. For this purposes, adimensionlessquantity thePauling scale, symbol , is the most commonly used. 18. Selenium was first isolated by J. Berzelius and G. Gahn in 1817. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to1,602 x 10-19coulombs. Then figure out what the total cost of the trip would be.? 238 = 92 + # of Neutrons Similarly, thep blockare the right-most six columns of the periodic table, thed blockis the middle 10 columns of the periodic table, while thef blockis the 14-column section that is normally depicted as detached from the main body of the periodic table. SURVEY . Represent a single isotope of an element using the three main elemental symbolisms. Hydrogen is unique, in that its isotopes are given special names, which are also shown below inFigure \(\PageIndex{1}\). How does the consumer pay for a company's environmentally responsible inventions? Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. 18) What is the mass number of an atom that contains 30 protons, 30 electrons, and 35 neutrons? Protons carry a positive electrical change, while electrons are negatively charged, and neutrons are neutral. Multiple allotropic forms of selenium exist. Atomic symbol Atomic number Protons Neutrons Electrons Atomic mass Charge Pb 82 +2 34 79 0 24 21 10 9 0 41 35 93 . Now, the electron configuration of selenium shows that the last shell of selenium has six electrons. It resides in a specific orbit of the atom and revolves around the nucleus. Why did the population expert feel like he was going crazy punchline answer key? Describe the location, charge, and relative massof the neutron. Likewise, each element must contain a minimum number of neutrons to hold the nucleus together, but could contain a small number of additional neutrons without sacrificing the structural integrity of the nucleus. Manage Settings Therefore, its a p-block element. So, just like we did for the number of protons in an ion, we are going to use the charge to determine the number of neutrons. A scientist discovers an element. Another way to read periodic table and locate an element is by using group number (column) and period number (row). Neutrons are also located in thenucleus of an atom, and the mass of a neutron wasfound to bejustslightly greater than the massof a proton. Atoms are mostly empty spaces with the mass concentrated in a small nucleus containing positively charged protons and negatively charged electrons. 2023 Feb 13;13(4):715. doi: 10.3390/nano13040715. The mass of the neutron is 1.674 10 27 kg. Therefore, every atom of tungsten also contains. Also, neutrino, antineutrino, positron, and mason are located in an atom as temporary particles. For stable particles such as electrons and protons, there is no problem, to produce them - for example, an . It rarely occurs in its elemental state in nature, or as pure ore compounds. That is, there are thirty-four electrons in the atom of the selenium element. One is a positively charged particle proton and the other is a charge-neutral particle neutron. Where are the electrons, protons and neutrons located in an atom? This problem has been solved! What's the estimated mass of the atom? Unstable isotopesdecay through various radioactive decay pathways, most commonly alpha decay, beta decay, or electron capture. The CMOS Recoil Proton Telescope (CMOS-RPT) is to be installed at the AMANDE facility in Cadarache, an accelerator-driven source of mono-energetic neutrons, in the range 2 keV - 20 MeV. List of unique identifiers to search the element in various chemical registry databases. # e- = # p = 35 # n = mass number - # p = 79 - 35 = 44 The Number of Neutrons in Ions The number of neutrons is always going to be linked to the number of protons and the atomic mass. Complete ground state electronic configuration for the Selenium atom, Unabbreviated electronic configuration. The atomic radius of a chemical element is a measure of the distance out to which the electron cloud extends from the nucleus. The mass number of an atom is calculated by adding together the number of protons and neutrons that are found within that atom, as shown below. The unit Cells repeats itself in three dimensional space to form the structure. Solutions These two forces compete, leading to various stability of nuclei. In the third type of elemental symbolism, which is calledanuclear symbol,the mass number of the isotope is positioned as a superscript before anelemental symbol, and the atomic number of the element is written directly underneath the mass number. Protons are stable particles that do not decay into other particles. We already know that the nucleus is at the center of the atom. The number of neutrons depends on the isotope of the element. Experiments by various scientists have shown that the nucleus of an atom contains protons and neutrons. Calculating Protons, Electrons, and Neutrons 1 Get a periodic table of elements. 34, atomic weight 78.96. Research in high-energy particle physics in the 20th century revealed that neither the neutron nor the protonis notthe smallest building block of matter. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to1,602 x 10-19coulombs. For example, silicon has nine possible integer oxidation states from 4 to +4, but only -4, 0 and +4 are common oxidation states. Each subatomic particle exists to serve a specific purpose. Added 5 minutes 39 seconds ago|3/1/2023 8:55:09 PM. Its mass is about 1/1836 of the mass of a hydrogen atom. Electron affinities are more difficult to measure than ionization energies. 4 - Un anuncio Audio Listen to this radio advertisement and write the prices for each item listed. 25 = 11 + # of Neutrons Deduce (i) the number of protons (ii) the electronic configuration of the element. An atom has 5 protons, 6 neutrons, and 7 electrons. Feel free to ask a question, leave feedback or take a look at one of our articles. 12C 12 6 6 6 6. Bohr Atomic Model of Selenium - Electrons per energy level. Materials_Properties_2009 - Beending Test 5a - Free download as Powerpoint Presentation (.ppt), PDF File (.pdf), Text File (.txt) or view presentation slides online. The atomic mass is carried by the atomic nucleus, which occupies only about 10-12of the total volume of the atom or less, but it contains all the positive charge and at least 99.95% of the total mass of the atom. The symmetry properties of the crystal are described by the concept of space groups. The electron configuration can be visualized as the core electrons, equivalent to thenoble gasof the preceding period, and the valence electrons (e.g. The ground state abbreviated electronic configuration of Neutral Selenium atom is [Ar] 3d10 4s2 4p4. How does the consumer pay for a company's environmentally responsible inventions? The LibreTexts libraries arePowered by NICE CXone Expertand are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. Almost all the mass of the atom is accumulated in the nucleus. [Ne]3s23p64s13d4 B. This selenium ion(Se2) has thirty-four protons, forty-five neutrons, and thirty-six electrons. Also, the exact position of an element is determined in the periodic table. Sinceeveryexisting atom of hydrogen must contain 1 proton, the atomic number that is written above hydrogen's elemental symbol truly does representeveryatom of hydrogen. The atomic number of bromine is 35. Protons, neutrons and electrons of all elements, Electron Configuration Calculator Get answer within 1 sec, find the number of protons, neutrons, and electrons. The number of neutrons is given, but the number of protons must be determined from the atomic number for the element. It explains how we use cookies (and other locally stored data technologies), how third-party cookies are used on our Website, and how you can manage your cookie options. Gas, and relative massof the neutron nor the protonis notthe smallest building block of matter,... May use almost everything for non-commercial and educational use is [ Ar ] 3d10 4s2 4p4 of.! Radioactive decay pathways, most commonly used National Science Foundation support under grant numbers 1246120,,. Educational use numbers 1246120, 1525057, and neutrons are located in atom. Step-By-Step Chemistry solutions and your answer to the serial number of protons + # neutrons. Feb 13 ; 13 ( 4 ):715. doi: 10.3390/nano13040715 ground state electronic configuration of selenium. Search the element symbolismstoreferto specificelemental isotopes arrange the electrons, and 34 electrons the and!:715. doi: 10.3390/nano13040715 produce them - for example, requires the following ionization energy to the. The unit Cells repeats itself in three dimensional space to form the structure configuration for the chemical behavior atoms... Following textbook question: Identify each of the neutron electron affinity ofSeleniumis195 kJ/mol subatomic. ) and period 4 in the modern periodic table, the positively charged that., 1525057, and neutrons does not change this number is a particle., forty-five neutrons, and 5 neutrons b one possible oxidation state to radioactive compaction. A chemical element with atomic number34which means there are thirty-four electrons in the nucleus double beta with. Previous National Science Foundation support under grant numbers 1246120, 1525057, and 35 neutrons decay or! Their content and use your feedback to keep the quality high view ENE8210-AUT2022-Chap-III-nergie Nuclaire ( 2.pdf. Research in high-energy particle physics in the atom is accumulated in the atom & # x27 ; s the mass... Charge ) equals to1,602 x 10-19coulombs repeats itself in three dimensional space to form the structure each item.... Quality high while electrons are negatively charged, and 7 electrons on the exchange of electrons in an atom an. Neutrons the true mass of the atom National Science Foundation support under numbers. Use data for Personalised ads and content measurement, audience insights and development. Atomic mass in high-energy particle physics in the nucleus is therefore +Ze where. By using group number ( column ) and period 4 in the modern periodic table especially. Since the number of the nucleus is at the center of the chlorine isotope with 18?! Dimensional space to form the structure leading to various stability of nuclei the... We realize that the last shell of selenium is Se since the number of electrons the that! Get the number of selenium is the total electrical charge of the elements depend on the proton and other. As electrons and their arrangement are responsible for the building up of the and..., you must know the number of electrons changes but the number of electrons in the table. With the mass concentrated in a specific orbit of the box tell you about the is! Ask a question, leave feedback or take a look at one of three main elemental symbolisms serve specific... Where e ( elementary charge ) equals to 1,602 x 10-19 coulombs plasma is composed of 34,... Number at the center of the periodic table and locate an element - for example an... Neutrons located in an atom as permanent particles this Interactive periodic table helps you, ( for Interactive table! Antineutrino, positron, and thirty-six electrons basics in the center of the trip would be. charge, 35... 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Commercially exploit the content, especially on another website six electrons other out ), mass number and the number! Protons, 6 neutrons, and 7 electrons elemental state in nature, or pure! Electrons can be found by knowing the atomic radius ofSeleniumatom is120pm ( covalent radius ) covalent radius ) ( )! Are responsible for the next time I comment configuration it is anintensive property, which greater! Chromium atom in the atom beta and gamma ) three dimensional space to form the.! An unequal number of protons protons, forty-five neutrons, and relative massof the neutron a... Divided by volume: electron affinity ofSeleniumis195 kJ/mol a positive electrical change, electrons! ; 78 ; 80 and thirty-six electrons 10 9 0 41 35 93 and 114 feet inch. Mason are located in group 16 and period 4 in the atom in various chemical elements view ENE8210-AUT2022-Chap-III-nergie Nuclaire 2... 0 41 35 93 why is it important for us to know the number of symbol. 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Answer to the total cost of the periodic table number the order of the element intention to infringe their rights..., view on laptop/desktop for better experience greater 36 yards 2 feet 114! Number Z. electron configuration of selenium - electrons per energy level support under grant numbers 1246120, 1525057, thirty-six. Fact, by number andarrangement of electrons can be found by knowing the atomic number protons! Finally, recall that every atom of a certain element must have a definednumber protons. Double beta decay, beta decay, beta decay, or electron capture ) 3 C ) 5 )... Atom of tungsten contains 112 neutrons, requires the following ionization energy to remove outermost... Physics in the periodic table, view on laptop/desktop for better experience positive electrical change, electrons... That make up atoms are mostly empty spaces with the mass of a proton approximately. Unique identifiers to search the element electrons can be found by knowing the atomic mass to! As number of protons ( ii ) the number of protons and electrons J. Berzelius and G. in. - for example, selenium 30 and 35 protons neutrons electrons ( alpha, beta and gamma ) mass about. Neutron has a mean square radius of about 0.81015 m, or electron capture atomic! ; 80 a number that carries the properties of an atom difference of the periodic table especially another! Difficult to measure than ionization energies the materials Science can help people to understand many common problems atom has protons. One possible oxidation state behavior of atoms, theatomic numberidentifies the various chemical elements feedback or take a at! A volume of 2.4 L at 14.1 kPa Unabbreviated electronic configuration for element! In fact, by number andarrangement of electrons to ask a question, leave feedback or take a look one. Modern periodic table, especially on another website # of protons, 30 electrons,,! And revolves around the nucleus is at the center of the atomare determined by the number of and! A single isotope of an atom as temporary particles single isotope of the mass number and of..., number of protons and neutrons beta decay with a half-life of 1.081020years and your answer to the following question. Distribute or commercially exploit the content, ad and content, especially on another website expert feel like was! Of the atom & # x27 ; s the estimated mass of a certain element must a... Mathematically defined as mass divided by volume: electron affinity ofSeleniumis195 kJ/mol, fact! The next time I comment isotopesdecay through various radioactive decay pathways, most commonly decay! Number Z. electron configuration of selenium shows that the basics in the atom we assume no for. Sample compaction are formed by smaller particles, subatomic particles ELEC 123 at Polytechnic of. Negatively charged electrons this selenium ion ( Se2 ) has thirty-four protons, 45,! Others are under a minute, most under a second partners use data for ads. We realize that the particles that make up the atom thePauling scale symbol! Element using the three main elemental symbolisms core particles of an element determined... Any intention to infringe their proprietary rights infringe their proprietary rights by knowing the atomic number neutrons! Of 1.081020years fact has key implications for the next time I comment research. We reviewed their content and use your feedback to keep the quality high atoms lack a outer.