Ibr4- molecular geometry - What is the molecular geometry of PZ6? square pyramidal O octahedral tetrahedral square planar QUESTION 2 Draw the Lewis structure of Br4 . What is the molecular geometry of IBr4? square square pyramidal trigonal bipyramidal octahedral QUESTION 3 A certain molecule has a central atom with four single bonds and two lone pairs.

 
A) square planar. The answer is A) square planar. Start from the Lewis structure of the tetrafluoroborate ion, BrF_4^(-). The molecule will have a total of 36 valence electrons - 7 from bromine, 7 from each of the four fluorine atoms, and one extra electron to give the ion the -1 charge. The bromine atom will be bonded to each of the four fluorine …. Decal roblox id

Here’s the best way to solve it. Expert-verified. 100% (1 rating) The molecular …. View the full answer. Previous question Next question. In this example,you will learn how to determine whether a molecule is polar.Here’s the best way to solve it. Identify the number of electron pairs around the central atom of the molecule. Determine the electron geometry (eg) and molecular geometry (mg) of PF5. O a. eg = trigonal bipyramidal, mg = trigonal pyramidal O b. eg = trigonal bipyramidal, mg = trigonal bipyramidal O c. eg = octahedral, mg = tetrahedral O d ...Fingerprint scanners like those on the latest iPhones could soon give way to another biometric identifier: The geometry of the veins in your hands. Fingerprint scanners like those ...This problem has been solved! You'll get a detailed solution from a subject matter expert that helps you learn core concepts. Question: Determine the molecular geometry and sketch each molecule or ion, using the bond conventions shown in "Representing Molecular Geometries on Paper" in Section 11.4 . a. BrF5 b.Contributors. 10.4: Geometry and Molecular Polarity is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts. VSEPR theory predicts the three-dimensional arrangement of atoms in a molecule. It states that valence electrons will assume an electron-pair geometry that minimizes repulsions between areas of ...Draw the Lewis Dot structure for IBr4-. Identify the electron cloud geometry, molecular geometry, the bond angles, and hybridization. (L Dot Structure on Slideshow)Answer. IBr⁻⁴ has a square planar molecular geometry, with iodine at the center and four bromine atoms at the corners. The Lewis dot structure consists of seven valence electron pairs around iodine—four bonding pairs and three lone pairs. To determine the molecular geometry of IBr⁻⁴, we first draw the Lewis dot structure.A step-by-step explanation of how to draw the IBr4 - Lewis Dot Structure. For the IBr4 - structure use the periodic table to find the total number of valence …eg = trigonal bipyramidal, mg = bent. c. eg = tetrahedral, mg = trigonal pyramidal. d. eg = trigonal planar, mg = trigonal planar. e. eg = trigonal planar, mg = tetrahedral. There are 2 steps to solve this one. Expert-verified.SCI c. PFS d. IFA+. Here’s the best way to solve it. 40. Determine the molecular geometry and sketch each molecule or ion, using the bond conventions shown in “Representing Molecular Geometries on Paper" in Section 11.4. a. BrFs b. SCI c. PFS d. IFA+.Together, the four sp 3 hybrid orbitals produce an approximately tetrahedral arrangement of electron pairs, which agrees with the molecular geometry predicted by the VSEPR model. A The CHCl 3 molecule has four valence electrons around the central atom. In the VSEPR model, the carbon atom has four electron pairs, and the molecular geometry is ...You'll get a detailed solution from a subject matter expert that helps you learn core concepts. See Answer. Question: What is the molecular geometry for the ion, BrF4+ ? A. bent B. T-shaped C. trigonal planar D. seesaw E. tetrahedral F. linear.Apr 28, 2022 · What is the molecular geometry of IBr4-? Updated: 4/28/2022. Wiki User. ∙ 11y ago. Best Answer. Square Planar, Like XeF4. Ammonium [NH4]+ ion Lewis dot structure, molecular geometry or shape, electron geometry, bond angle, hybridization, formal charges, polar vs non-polar. [NH 4] + is the chemical formula that represents the ammonium ion. The ammonium ion is an important nitrogen source for plants. It is used in the chemical industry for fertilizer manufacturing.Geometry Dash is a popular rhythm-based platform game that has gained a massive following since its release in 2013. With its addictive gameplay and challenging levels, it has beco...Introduction. Molecular compounds are formed when two non-metals share valence electrons forming a covalent bond. This results in two types of orbitals; bonding orbitals, where the valence electrons are shared between two nuclei, and non-bonding orbitals (lone pairs), where the valence electrons are localized to one nucleus.-Electron geometry is the arrangement of the electron groups.-Molecular geometry is the geometrical arrangements of the atoms. -When a molecule contains one or more lone pairs, then the molecular geometry differs from the electron geometry. This is because the lone pair exerts slightly greater repulsion than a bonding pair. Question: Consider the structure of IBr4- a) What are the formal charges on I? [a] b) What are the formal charges on Br? [b] c) What is its molecular geometry? Please choose from the following and answer using the letter code. [c] A. Seesaw B. Tetrahedral C. Sqaure. eg = trigonal bipyramidal, mg = bent. c. eg = tetrahedral, mg = trigonal pyramidal. d. eg = trigonal planar, mg = trigonal planar. e. eg = trigonal planar, mg = tetrahedral. There are 2 steps to solve this one. Expert-verified.What is the molecular geometry of PZ6? square pyramidal O octahedral tetrahedral square planar QUESTION 2 Draw the Lewis structure of Br4 . What is the molecular geometry of IBr4? square square pyramidal trigonal bipyramidal octahedral QUESTION 3 A certain molecule has a central atom with four single bonds and two lone pairs.Ans 8 : To determine the polarity of a covalent bond , we subtract the electr …. Determine the polarity of the bonds in IBrs if the electronegativity of I is 2.5 and Br is 2.8 8. 9. Determine the molecular polarity of IBr4 10. Compare the ideal equatorial bond angles of the electron geometry with the actual equatorial bond angles of the ...Determine the molecular geometry IBr−4 and make a sketch. Here’s the best way to solve it. Expert-verified. 94% (16 ratings) Share Share. Here’s how to approach this question. Determine the number of electron pairs around the central atom and consider both bonding pairs and lone pairs. View the full answer.Find out the molecular structure of any compound. Get the free "Molecular Structure Creator" widget for your website, blog, Wordpress, Blogger, or iGoogle. Find more Chemistry widgets in Wolfram|Alpha. Answer to Solved PCl3 , ICl3 , NO2 , IF5 , XeF2 , IBr4 - , SF6 , | Chegg.com What is the molecular geometry of PZ6? square pyramidal O octahedral tetrahedral square planar QUESTION 2 Draw the Lewis structure of Br4 . What is the molecular geometry of IBr4? square square pyramidal trigonal bipyramidal octahedral QUESTION 3 A certain molecule has a central atom with four single bonds and two lone pairs.For more complicated molecules the geometry at each atom may have to be determined in order to get an dea of the overall shape. For example; four electron pairs are distributed in a tetrahedral shape. If these are all bond pairs the molecular geometry is tetrahedral (e.g. CH 4). If there is one lone pair of electrons and three bond pairs theWhat is the molecular geometry of PZ6? square pyramidal O octahedral tetrahedral square planar QUESTION 2 Draw the Lewis structure of Br4 . What is the molecular geometry of IBr4? square square pyramidal trigonal bipyramidal octahedral QUESTION 3 A certain molecule has a central atom with four single bonds and two lone pairs.Formaldehyde, also known as H2CO, has trigonal planar geometry. This molecule consists of two single-bonded hydrogens attached to a carbon center that also has an oxygen double bon... Science. Chemistry. Chemistry questions and answers. H30 IBr4 HCN Molecular Geometry: Molecular Geometry: M Molecular Geometry: Molecular Geometry IF3 IF4 IFs IF202 Molecular Geometry: Molecular Geometry: Molecular Geometry: Molecular Geometry: IOFs NCl3 NF2 NO2 Molecular Geometry: Molecular Geometry: Molecular Geometry: Molecular Geometry. Determine the molecular geometry of SO_4^{2-}. Identify the (ideal) molecular geometry for BF3 - Trigonal pyramidal - Tetrahedral - Bent - Trigonal - Planar; Determine whether the following molecule is polar or nonpolar: SCl_2. Determine the molecular geometry of XeF4. Determine the electron geometry, molecular geometry, and polarity of XeO3.Introduction. There is a three step approach to determining the geometry of a molecule. Determine the Lewis dot structure of the compound. Determine the Electron geometry from the Lewis dot structure. Determine the molecular geometry.An explanation of the molecular geometry for the CBr4 (Carbon tetrabromide) including a description of the CBr4 bond angles. The electron geometry for the Ca...Here’s the best way to solve it. Identify the number of electron pairs around the central atom of the molecule. Determine the electron geometry (eg) and molecular geometry (mg) of PF5. O a. eg = trigonal bipyramidal, mg = trigonal pyramidal O b. eg = trigonal bipyramidal, mg = trigonal bipyramidal O c. eg = octahedral, mg = tetrahedral O d ...Get four FREE subscriptions included with Chegg Study or Chegg Study Pack, and keep your school days running smoothly. 1. ^ Chegg survey fielded between Sept. 24–Oct 12, 2023 among a random sample of U.S. customers who used Chegg Study or Chegg Study Pack in Q2 2023 and Q3 2023. Respondent base (n=611) among approximately 837K …The carbon atom has an electron pair arrangement of a tetrahedron, and the molecular geometry is a tetrahedral shape. Exercise \(\PageIndex{1}\) Use the VSEPR model to predict the number of atoms and lone pairs attached, the electron pair arrangement, and molecular geometry for the central atom(s) in each compound. and then describe the ...Explanation: Number of Hybrid orbitals = [ (Number of valance e A − in Central atom) + (Number of monovalent atoms)- (O... Using the VSEPR model, predict the electron doma in geometry and the molecular geometry of each species (bent, linear, octahedral, seesaw, square planar, square pyramidal, T-shaped, tetrahedral, trigonal bipyramidal ...Question: Consider the following molecular formulas SBr2 CH2Cl2 CS2 COF2 C2F4 SeCl4 IF2- IBr4- For each of these molecules, you'll need to make hand written drawings of A Lewis dot structure (0.5 point per molecule) An electron-pair geometry with vectors indicating bond dipole moments. Use dash and wedge bonds to indicate perspective.IBr4. Keenan Mintz University of Miami 04:25. Problem 62 Determine the molecular geometry and draw each molecule or ion, using the bond conventions shown in the "Representing Molecular Geometries on Paper" section of this chapter (see Section 5.9). ... Determine the molecular geometry and draw it accurately. c. Indicate the polarity of any ...The bond angle in NOBr is 120 degrees. The molecular geometry of NOBr is bent and there is lone pair present on the central atom. This makes bond angle 120 degrees. NOBr Lewis structure octet rule. Atoms tend to have eight electrons in their valence shell by sharing of electrons or transfer of electrons between atoms. This is what we call the ...Study with Quizlet and memorize flashcards containing terms like Determine the molecular geometry and make a sketch of the molecule or ion using the bond conventions in Section 10.4: SF4, Determine the molecular geometry and make a sketch of the molecule or ion using the bond conventions in Section 10.4: ClF3, Determine the molecular geometry …Corresponding angles are easy to find once you know what to look for. Advertisement Geometry is packed with terminology that precisely describes the way various points, lines, surf... Science. Chemistry. Chemistry questions and answers. H30 IBr4 HCN Molecular Geometry: Molecular Geometry: M Molecular Geometry: Molecular Geometry IF3 IF4 IFs IF202 Molecular Geometry: Molecular Geometry: Molecular Geometry: Molecular Geometry: IOFs NCl3 NF2 NO2 Molecular Geometry: Molecular Geometry: Molecular Geometry: Molecular Geometry. Expert's Answer. Determine the molecular geometry of IBr4−IBr4− using the bond conventions shown in the “Representing Molecular Geometries on Paper” section of this chapter (see Section 5.9 in the textbook). Determine the molecular geometry of... Chemistry questions and answers. Part A Determine the molecular geometry of BrF5. seesaw trigonal bipyramidal square pyramidal octahedral Part B Make a sketch of BrF5. Draw the molecule by placing atoms on the grid and connecting them with bonds using the straight line, hatched wedge and solid wedge 3D.Molecular geometry takes into account the electrons as well when determining the geometry. The geometry of KrF2 is trigonal bipyramidal. The molecular shape does take into account the lone pairs on the central atom. Thus, the molecular shape of KrF2 is linear. The bond angle formed between each atom is 180 degrees. The notation AXN can be used ...An explanation of the molecular geometry for the IBr3 (Iodine tribromide) including a description of the IBr3 bond angles. The electron geometry for the Iodi...In this example,you will learn how to determine whether a molecule is polar.Building an arched doorway can be a very satisfying do-it-yourself project. Building an archway requires a little geometry and patience, but the rewards Expert Advice On Improving ...Answered step-by-step. Determine the molecular geometry and sketch each molecule or ion using the bond conventions shown in "Representing Molecular Geometries on Paper" in Section 10.4. a. SF4 b. ClF3 c. IF2^- d. IBr4^-. Determine the molecular geometry and sketch each molecule or ion using the bond conventions shown in …Lewis structure of IBr4- ion contains four single bonds between the Iodine (I) atom and each Bromine (Br) atom. The Iodine atom (I) is at the center and it is surrounded by 4 Bromine atoms (Br). The Iodine atom has 2 lone pairs and it also has -1 formal charge. For exhibiting the see saw geometry there should be 5 electron domain. From the structures in the subpart a of the question, we can infer that the molecules P F 4 − \mathrm{PF_{4}^{-}} P F 4 − and C l F 4 + \mathrm{ClF_{4}^{+}} Cl F 4 + exhibit see-saw molecular geometry Read Sections 11.3, 11.4; Watch KCV 11.3, IWE 11.2a)CI4b)NCl3c)OF2d)H2S Determine the molecular geometry and sketch each molecule or ion using the bond conventions shown in. Determine the electron geometry, molecular geometry, and idealized bond angles for each molecule. In which cases do you expect deviations from the idealized bond angle? Identify the electron and molecular geometry for SiBr 4.What is the bond angle and is it expected to deviate from the ideal? Here’s the best way to solve it. Expert-verified. 100% (1 rating) The molecular …. View the full answer. Previous question Next question. 1:48 minutes. Problem 39b Tro - 4th Edition. Textbook Question. Determine the molecular geometry and sketch each molecule or ion using the bond conventions shown in …Question: Consider the structure of IBr4- a) What are the formal charges on I? [a] b) What are the formal charges on Br? [b] c) What is its molecular geometry? Please choose from the following and answer using the letter code. [c] A. Seesaw B. Tetrahedral C. Sqaure.Geometry Dash is a popular rhythm-based platform game that has gained a massive following since its release in 2013. With its addictive gameplay and challenging levels, it has beco...IBr4 Molecular Geometry Formula Resonance Structures Electronic Molecular Geometry Geometry CIO2- SO42- Page 5 of S . Not the question you’re looking for? Post any question and get expert help quickly. Start learning . Chegg Products & Services. Cheap Textbooks; Chegg Study Help; Citation Generator;Introduction. There is a three step approach to determining the geometry of a molecule. Determine the Lewis dot structure of the compound. Determine the Electron geometry …Molecular geometry is the three-dimensional arrangement of the atoms that constitute a molecule. It gives information about the general shape of the molecule as well as bond lengths, bond angles, torsional angles and any other geometrical parameters that determine the position of each atom. Q5.Get four FREE subscriptions included with Chegg Study or Chegg Study Pack, and keep your school days running smoothly. 1. ^ Chegg survey fielded between Sept. 24–Oct 12, 2023 among a random sample of U.S. customers who used Chegg Study or Chegg Study Pack in Q2 2023 and Q3 2023. Respondent base (n=611) among approximately 837K invites.The total valence electron is available for drawing the carbon tetrabromide ( CBr4) lewis structure is 32. The hybridization of CBr4 is Sp 3 and the bond angle of 109.5°. CBr4 is a nonpolar molecule because of the zero net dipole moment caused by its symmetrical structure. The molecular geometry of CBr4 is Tetrahedral.The carbon atom has an electron pair arrangement of a tetrahedron, and the molecular geometry is a tetrahedral shape. Exercise \(\PageIndex{1}\) Use the VSEPR model to predict the number of atoms and lone pairs attached, the electron pair arrangement, and molecular geometry for the central atom(s) in each compound. and then describe the ...Quizlet is a lightning fast way to learn vocabulary. Determine the molecular geometry and make a sketch of the molecule or ion using the bond conventions in Section 10.4: [IBr4]-Get four FREE subscriptions included with Chegg Study or Chegg Study Pack, and keep your school days running smoothly. 1. ^ Chegg survey fielded between Sept. 24–Oct 12, 2023 among a random sample of U.S. customers who used Chegg Study or Chegg Study Pack in Q2 2023 and Q3 2023. Respondent base (n=611) among approximately 837K invites.Jan 30, 2023 · Geometry of Molecules. Molecular geometry, also known as the molecular structure, is the three-dimensional structure or arrangement of atoms in a molecule. Understanding the molecular structure of a compound can help determine the polarity, reactivity, phase of matter, color, magnetism, as well as the biological activity. Tetrahedral Geometry. Tetrahedral geometry is a bit harder to visualize than square planar geometry. Tetrahedral geometry is analogous to a pyramid, where each of corners of the pyramid corresponds to a ligand, and the central molecule is in the middle of the pyramid. This geometry also has a coordination number of 4 because it …IBr4- lewis structure has an Iodine atom (I) at the center which is surrounded by four Bromine atoms (Br). There are 4 single bonds between the Iodine atom (I) and each Bromine atom (Br). There are 2 lone pairs on the Iodine atom (I) and 3 lone pairs on all the four Bromine atoms (Br). Question: Using the VSEPR model, predict the electron domain geometry and the molecular geometry of each species (bent, linear, octahedral, seesaw, square planar, square pyramidal, T-shaped, tetrahedral, trigonal bipyramidal, trigonal planar, or trigonal pyramidal). Part 1 of 4 PF5 Electron Domain Geometry: (Choose one) Molecular Geometry ... Determine the molecular geometry for IF 4 +. trigonal bipyramidal seesaw square pyramidal square planar T-shaped * Incorrect; Try Again; 9 attempts remaining The trigonal bipyramidal molecular geometry that occurs with five electron groups aro and count the total number of electron arouos around the central atom in IF 1 +.Deter Determine the …Jun 23, 2023 · Step 3: Connect each atoms by putting an electron pair between them. Now in the IBr4 molecule, you have to put the electron pairs between the iodine atom (I) and bromine atoms (Br). This indicates that the iodine (I) and bromine (Br) are chemically bonded with each other in a IBr4 molecule. Determine the molecular geometry and sketch each molecule or ion, using the bond conventions shown in 'Representing Molecular Geometries on Paper' in Section 10.4. c. PF5. Determine the molecular geometry and sketch each molecule or ion, using the bond conventions shown in 'Representing Molecular Geometries on Paper' in Section 10.4. b. SCl6. 381. Lewis structure of IBr4- ion contains four single bonds between the Iodine (I) atom and each Bromine (Br) atom. The Iodine atom (I) is at the center and it is surrounded by 4 Bromine atoms (Br). The Iodine atom has 2 lone pairs and it also has -1 formal charge.Determine the molecular geometry of SO_4^{2-}. Identify the (ideal) molecular geometry for BF3 - Trigonal pyramidal - Tetrahedral - Bent - Trigonal - Planar; Determine whether the following molecule is polar or nonpolar: SCl_2. Determine the molecular geometry of XeF4. Determine the electron geometry, molecular geometry, and polarity of XeO3.μ (Polarity) >0. Disphenoidal or seesaw (also known as sawhorse [1]) is a type of molecular geometry where there are four bonds to a central atom with overall C 2v molecular symmetry. The name "seesaw" comes from the observation that it looks like a playground seesaw. Most commonly, four bonds to a central atom result in tetrahedral or, less ...In the inter halogen compound IBr4 , iodine (I) is the central atom with a formal charge of In the inter-halogen compound IBr4-, iodine (I) is the central atom with a formal charge of -1, covalently bonded to four bromine (Br) atoms. A label indicating the geometry predicted by VSEPR theory i.e. linear, trigonal planar, IBr 4-. Submit drawings for the molecule of. Electron-pair geometry with vectors indicating bond dipole moments. Use dash and wedge bonds to indicate perspective. Molecular structure with a vector indicating dipole moment. This problem has been solved! You'll get a detailed solution from a subject matter expert that helps you learn core concepts. Question: Draw the Lewis structure and 3D shape/structure (with perspective) for IBr4*. State the electron pair geometry and the molecular geometry for your structure in #9. What is/are the bond angle (s) in your ...What is the molecular geometry of IBr4-? Determine the molecular geometry of BrF_5. (a) Seesaw (b) Trigonal bipyramidal (c) Square pyramidal (d) Octahedral; Give the molecular geometry for GeO_2. Determine the electron geometry and molecular geometry of SiF4. Determine the molecular geometry and bond angles of CFCl3.molecular geometry of AsH2cl , IBr4- , HCN , SeS2 , XeF2 , BrO2- , BrF3 , SiF4 , SI5- , TeS3 ... | answersarena.comMolecular geometry is the three-dimensional arrangement of the atoms that constitute a molecule. It gives information about the general shape of the molecule as well as bond lengths, bond angles, torsional angles and any other geometrical parameters that determine the position of each atom. Q5.The molecular geometry, or three-dimensional shape of a molecule or polyatomic ion, can be determined using valence-shell electron-pair repulsion (abbreviated VSEPR and pronounced “VES-per”) theory, in which the basic principle is valence electrons around a central atom stay as far apart as possible to. minimize the repulsions.

Question: Choose the correct sketch of IBr4-using the bond conventions shown in the "Representing Molecular Geometries on Paper" section of Section 5.9 in the textbook. ... To determine the molecular geometry, first calculate the steric number for the given molecule IBr4-. The steric number is calculated by using the formula (number of bond .... Shawn wayans wife

ibr4- molecular geometry

We are increasingly out of touch with who we are, and that’s a problem. Before dying at the age of 39, Blaise Pascal made huge contributions to both physics and mathematics, notabl...Hard. Solution. Verified by Toppr. Correct option is D) According to the VSEPR theory, ICl₃ is sp³d hybridized with 3 sigma bond pairs and 2 lone pairs as shown in the figure. Thus, it is T-shaped.Expert's Answer. Determine the molecular geometry of IBr4−IBr4− using the bond conventions shown in the “Representing Molecular Geometries on Paper” section of this chapter (see Section 5.9 in the textbook). Determine the molecular geometry of...NOCl consists of one Nitrogen atom, one Oxygen atom, and one Chlorine atom. In its most stable state, Nitrogen acts as the central atom and forms a double bond with Oxygen. It also possesses a lone pair and a covalent bond with Chlorine. Since there are three elements, NOCl has no overall hybridization.The molecular geometry of ClO2 is a bent or V-shape, according to Bristol ChemLabS. ClO2 is the molecular formula for chlorine dioxide. It is a yellowish-green gas that crystallize...Hard. Solution. Verified by Toppr. Correct option is D) According to the VSEPR theory, ICl₃ is sp³d hybridized with 3 sigma bond pairs and 2 lone pairs as shown in the figure. Thus, it is T-shaped.What is the molecular geometry of IBr4-? Updated: 4/28/2022. Wiki User. ∙ 11y ago. Best Answer. Square Planar, Like XeF4.Question. Solved step-by-step. Submitted by Ashley G., Sep. 24, 2021, 04:55 a.m. Which statement about IBr4 are TRUE? The molecular geometry (or shape) is tetrahedral: …Building an arched doorway can be a very satisfying do-it-yourself project. Building an archway requires a little geometry and patience, but the rewards Expert Advice On Improving ...The video also talks about the molecular geometry, bond angle, and hybridization for IBr4-. This video shows you how to draw the lewis structure for IBr4-. It also tells you whether or not if IBr4- is polar or nonpolar. Click here👆to get an answer to your question ️ what is the geometry of the ibr2 ion Question: Determine the molecular polarity of IBr4 9. 10. Compare the ideal equatorial bond angles of the electron geometry with the actual equatorial bond angles of the molecular geometry. Why is there a difference?Brf2 Lewis structure lone pairs. If we look into central atom Br in the BrF2 Lewis structure it has 5 non bonded electrons in it. It means it has Br has 2 lone pair of electrons and a single unpaired electron. There are 6 non bonded electrons present in each fluorine atom i.e. there are 3 lone pair of electrons present in each fluorine atom.Geometry is an important subject for children to learn. It helps them understand the world around them and develop problem-solving skills. But learning geometry can be a challenge ...Asked for: number of atoms and lone pairs attached, the electron pair arrangement and molecular geometry. Strategy: Using the VSEPR approach to determine the number of ….

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