Naming & Formula Writing for Type 2 Ionic Compounds What is a Type 2 Compound? Steps for naming: Write the name of the metal. Ionic and Covalent Compounds Name: KEY!! Covalent compounds are formed when two or more nonmetal atoms bond by sharing valence electrons. c) (NH4)3PO4 Show Answer (c) ammonium phosphate. For an ionic compound to be stable, the positive charges have to equal the negative charges. In all cases, ionic compound naming gives the positively charged cation first, followed by the negatively charged anion. Ionic How To Compounds Names Write. and Mg²? In MgO the magnesium is +2 and the oxygen (O) is –2 and so again the charges cancel each … Ionic compound nomenclature or naming is based on the names of the component ions. Name each ionic compound. 1. NH 4 + and NO 3 − K + and Cr 2 O 7 2− Cu + and CO 3 2− Na + and HCO 3 − 14. Which french saint is associated which the town of Lourdes? If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked. Ionic compounds include salts, oxides, hydroxides, sulphides, and the majority of inorganic compounds. For example, consider FeCl 2 … Compounds of these metals with nonmetals are named with the same method as compounds in the first category, except the charge of the metal ion is specified by a Roman numeral in parentheses after the name of the metal. The name for CaCl_2 is calcium chloride. Acid Orange 20 may be physically removed from the air, mainly by wet deposition. This is a binary ionic compound, a metal and a non metal. These compounds are binary, in that they are made up of two types of elements. Al(HSO 4) 3; Mg(HSO 4) 2; 15. When did organ music become associated with baseball? These metals can have more than one charge or oxidation state. When you name ionic compounds, you write the name of the metal first and then the nonmetal. Josh Kenney explains how to name simple binary ionic compounds and ionic compounds with polyatomic ions. Name the nonmetal by its elemental name and an -ide ending. Copyright © 2020 Multiply Media, LLC. Potassium chloride. Property Name Property Value Reference; Molecular Weight: 460.4 g/mol: Computed by PubChem 2.1 (PubChem release 2019.06.18) Hydrogen Bond Donor Count: 2: Computed by Cactvs 3.4.6.11 (PubChem release 2019.06.18) Hydrogen Bond Acceptor Count: 5: Computed by Cactvs 3.4.6.11 (PubChem release 2019.06.18) Rotatable Bond Count: 8 Give two names for each compound. The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply. Ca2C is calcium chloride. Copyright © 2020 Multiply Media, LLC. Cross each element’s oxidation number to the lower. Name metals that can have different oxidation states using roman numerals to indicate positive charge. What is the percent by volume of a solution formed by mixing 25mL of isopropanol with 45 mL of water? Give two names for each compound. In chemistry, an ionic compound is a chemical compound composed of ions held together by electrostatic forces termed ionic bonding. 3. It is made up of a metal from columns 3-12, 14 and a nonmetal. You could say, okay if the cobalt has a charge of three plus you could figure out its formula right over here, or as we just did in this video, you could go from the formula to the actual name. CaCl 2; AlF 3; KCl; Solution. Names of Ionic Compounds The name of an ionic compound is built from the names of the positive and negative ions in the compound. Here are the principal naming conventions for ionic compounds, along with examples to show how … Ion exchange agents This page was last edited on 31 October 2020, at 06:26. One you have done that, you can follow the following rules to generate the names. How old was queen elizabeth 2 when she became queen? We differentiate between two types of compounds: IONIC and COVALENT. From a list of almost 2000 names and formulas, students will be given the opportunity to practice their ability to name ionic compounds, given the formula, and determine the formula given the name. The structure of an ionic compound depends on the relative sizes of the cations and anions. Tools. 2. To form the full name of an ionic compound, simply join the names of the positive and negative ions together. It is not calcium(II) chloride because calcium forms only one cation when it forms an ion, and it has a characteristic charge of 2+. The compound is neutral overall, but consists of positively charged ions called cations and negatively charged ions called anions. Calcium oxide (CaO) used in the pulp manufacturing. AnNeg(-), PosCat (+) The answer is therefore B. Examples; CaBr 2 → “calcium bromide” Al 2 O 3 → “aluminium oxide” Na 3 P → “sodium phosphide“ Examples Involving Polyatomic Ions (NH 4) 2 S → “ammonium sulfide” K 2 CO 3 → “potassium carbonate“ 3. The charge of the metal ion is determined from the formula of the compound and the charge of the anion. What is plot of the story Sinigang by Marby Villaceran? Compounds of these metals with nonmetals are named with the same method as compounds in the first category, except the charge of the metal ion is specified by a Roman numeral in parentheses after the name of the metal. b) CoSO4 Show Answer (b) cobalt(II) sulfate. Ammonia, NH3 is a COMPOUND while nitrogen and hydrogen are _ELEMENTS_. How long will the footprints on the moon last? Practice naming ionic compounds when given the formula If you're seeing this message, it means we're having trouble loading external resources on our website. This chemistry video tutorial explains how to name ionic compounds. Se 2−, the selenide ion. Can you name binary ionic compounds? Start studying Ionic compounds: Names from formulas (reverse). What is the name of the ionic compound Ni3(PO4)2? Tools. The name of an ionic compound is name of cation + name of anion (two words) You will have to memorize the formulas of the common ions. Who is the longest reigning WWE Champion of all time? The ionic compound for Potassium is K+ and the ionic compound for Oxide is O2-. Give the formula for each of the following ionic compounds: a) ammonium carbonate Show Answer (a) (NH 4) 2 CO 3. b) calcium iodide Show Answer (b) CaI 2. c) … Due to the ionic nature of C.I. Therefore, the number of cations and anions in an ionic compound must be balanced to make an electrically neutral molecule. And you could go either way. ! As an additional step, you'll need to calculate the charge of the metal ion if you're working with a transition metal. In NaCl, sodium (Na) is +1 and the chloride is –1. Why don't libraries smell like bookstores? 5. All Rights Reserved. [:C triple bond C:]^2- Ca^2+. All Rights Reserved. What are the release dates for The Wonder Pets - 2006 Save the Ladybug? The formula of calcium carbide is CaC2. Ionic, or saltlike, amides are strongly alkaline compounds ordinarily made by treating ammonia, an amine, or a covalent amide with a reactive metal such as sodium. And you could go either way. Name each of the following ionic compounds: a) K2S Show Answer (a) potassium sulfide. d) Ca(CIO)2 Show Answer (d) calcium hypochlorite. CaCl_2 = Calcium and Chlorine = Calcium Chloride Step 1 - write name of first element just as it is on the periodic table Calcium Step 2 - write name of second element but change -ine ending to -ide. Catalyst. Chemical Formula Type of Compound: Ionic or Covalent Compound Name 21) CdBr 2 22) Cr(Cr 2O 7) 3 23) SBr 2 24) (NH 4) 2CrO 4 The name of an ionic compound is name of cation + name of anion (two words) You will have to memorize the formulas of the common ions. Ionic compounds consist of cations (positive ions) and anions (negative ions). There is no Ca2C. Write the symbol for each ion and name them. To name an ionic compound, you simply need to find the names of the cation and anion present in the compound and make sure to revise the ends of metal names as needed. Example 2. Name this ionic compound: BeBr2. In all cases, ionic compound naming gives the positively charged cation first, followed by the negatively charged anion. Therefore, something like sodium hydroxide ($\ce{Na+OH-}$, definitely an ionic compound) could actually be correctly called a salt. NAMING CATIONS. I think you mean CaC2, calcium carbide. This is a how-to guide for finding names and formulas of ionic compound. Name the formula for this ionic compound: Calcium carbide. Watch more videos on http://www.brightstorm.com/science/chemistry SUBSCRIBE FOR All OUR VIDEOS! Cu 2+ copper (II) or cupric Cl-chloride ANSWER: Copper (II) chloride or cupric chloride When naming ionic compounds, the cation retains the same name as the element. It is not calcium (II) chloride because calcium forms only one cation when it forms an ion, and it has a characteristic charge of 2+. First, write out the name of the metal, followed by the name of the non-metal with its new ending. Acid Orange 20 should exist solely in the particulate phase in the ambient atmosphere. Does pumpkin pie need to be refrigerated? How can I name ionic compounds with three elements? What is the name for ionic compound Ca2C? What is the name of the ionic compound BaCO 3? Nomenclature, a collection of rules for naming things, is important in science and in many other situations.This module describes an approach that is used to name simple ionic and molecular compounds, such as NaCl, CaCO 3, and N 2 O 4.The simplest of these are binary compounds, those containing only two elements, but we will also consider how to name ionic compounds containing … When did organ music become associated with baseball? You could have other ionizations of cobalt in other ionic compounds, but this one is cobalt (III) sulfide. Cations that can have only one charge, such as Na? It includes examples with polyatomic ions and transition metals. In general, ionic compounds form when _METALS & NONMETALS _combine together. [:C triple bond C:]^2- Ca^2+. Formulas of Ionic Compounds. This contains the C22- So K+ + O2- = K20 From MILLY Chloride. Here are the principal naming conventions for ionic compounds, along with examples to show how … Learn vocabulary, terms, and more with flashcards, games, and other study tools. Using the names of the ions, this ionic compound is named calcium chloride. 2. Name the ionic compound formed by each pair of ions. Naming Binary Ionic Compounds with a Metal That Forms More Than One Type of Cation. 2. Using the names of the ions, this ionic compound is named calcium chloride. That's because the Ca has a 2+ charge the then the two carbons bond via a triple bond, leaving a 2- charge. Suppose that you want to name the compound that results from the reaction of lithium and sulfur. Co(HCO 3) 2; LiHCO 3; AnswerS. This is an categorically simple means to specifically get lead by on-line. You could have other ionizations of cobalt in other ionic compounds, but this one is cobalt (III) sulfide. It is also the solution to the first practice quiz question 4. Using the names of the ions, this ionic compound is named calcium chloride. Naming Binary Ionic Compounds. For example, consider binary ionic compounds of iron and chlorine. Calcium carbide. Does pumpkin pie need to be refrigerated? Full Names for Ionic Compounds. The charge of the metal ion is determined from the formula of the compound and the charge of the anion. Not any name we want like Jeff or Larry, there's rules for how to name them. Interestingly, IUPAC states that a "salt" is "a chemical compound consisting of an assembly of cations and anions".Under this definition, all ionic compounds are salts, and all salts are ionic compounds. In all cases, ionic compound naming gives the positively charged cation first, followed by the negatively charged anion. Name an ionic compound by the cation followed by the anion. Suppose that you want to name the compound that results from the reaction of lithium and sulfur. There is no Ca2C. Ionic Compound Naming and Formula Writing List 1. Predict which forms an anion, which forms a cation, and the charges of each ion. Particulate-phase C.I. Name each ionic compound. Which french saint is associated which the town of Lourdes? When you name ionic compounds, you write the name of the metal first and then the nonmetal. Ca2C. Then, use the correct naming rules to write the correct names for each compound. What are the release dates for The Wonder Pets - 2006 Save the Ladybug? Ionic compounds are compounds made up of ions. Ionic compound nomenclature or naming is based on the names of the component ions. Ionic Compound Naming – Chilton Honors Chemistry Naming Ionic Compounds – Answer Key Give the name and molar mass of the following ionic compounds: Name 1) Na 2 CO 3 sodium carbonate 2) NaOH sodium hydroxide 3) MgBr 2 magnesium bromide 4) KCl potassium chloride 5) … How to write the names for binary ionic compounds. Cations have positive charge. The Anion here is Nitrate, NO3(1-)2 because it has a negative electric charge. The name of this ionic compound is aluminum fluoride. Name the formula for this ionic compound: Sodium phosphide. ! Can you write formulas for binary ionic compounds? Answer . You first write the name of the metal, lithium, and then write the name of the nonmetal, adding an -ide ending so that sulfur becomes sulfide. Example \(\PageIndex{3}\): Naming Ionic Compounds. An ionic compound is formed by the complete transfer of electrons from a metal to a nonmetal, and the resulting ions have achieved an octet. The name of the positive cation is given first, followed by the name of the negative anion. There is one more step when naming compounds formed from transition metals Here is some tips, and tricks for naming ionic compounds. In general, molecular compounds form when NONMETALS_combine together. Na2co3 Ionic Compound Name Getting the books na2co3 ionic compound name now is not type of inspiring means. Acid Orange 20 makes this compound essentially non-volatile, therefore C.I. It is a compound of tin and fluorine (if it has two parts to its name or ends in -ide, it is not an element). Name this ionic compound: Ca2C. This compound is Calcium Nitrate, made up of Ca(2+) and NO3(1-). MgCl2. The name of this ionic compound is aluminum fluoride. How does arousal and anxiety affect your training? One you have done that, you can follow the following rules to generate the names. Ionic_Covalent Names: Chapter 9 Honors Chemistry Ionic & Covalent Compound Naming First, identify whether these compounds are ionic or covalent. Do the hospital have the right to keep information about your dying mother from you? Practice until it Top Custom Essay Editor Service Usa becomes second nature. In chemistry, an ionic compound is a chemical compound composed of ions held together by electrostatic forces termed ionic bonding.The compound is neutral overall, but consists of positively charged ions called cations and negatively charged ions called anions.These can be simple ions such as the sodium (Na +) and chloride (Cl −) in sodium chloride, or polyatomic species such as the … CaCl_2 = Calcium and Chlorine = Calcium Chloride Ionic Compounds: Ionic compounds result from ionic bonds, which are two ions that are stuck together due to their opposite electrical charges. You could not lonely going later than ebook growth or library or borrowing from your links to right to use them. Anions have negative charge. Ionic Compound Structure. You first write the name of the metal, lithium, and then write the name of the nonmetal, adding an -ide ending so that sulfur becomes sulfide. Na3P. The name of this ionic compound is potassium chloride have the same name as the metal (sodium or magnesium). The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply. Examples of ionic compound names are given below. 1. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Describes ternary ionic compounds, formulas of ternary ionic compounds, and naming ternary ionic compounds. Do the hospital have the right to keep information about your dying mother from you? Give the symbol and name for the ion with 34 protons and 36 electrons. Why don't libraries smell like bookstores? Use both the Stock and common systems, where appropriate. The answer cannot be A because Nitrite is NO2(-) which is not matching the compound NO3(-) Ionic compounds consist of cations (positive ions) and anions (negative ions). Ionic solids are held together by the electrostatic attraction between the positive and negative ions. Name the metal by its elemental name. Ionic compound nomenclature or naming is based on the names of the component ions. Ionic Compounds - Names and Formulas. What is the percent by volume of a solution formed by mixing 25mL of isopropanol with 45 mL of water? If you are given a formula for an ionic compound whose cation can have more than one possible charge, you must first determine the charge on the cation before identifying its correct name. ! We have to know how to name ionic compounds. A step-by-step video explanation. The anion’s name is similar to the elemental name, but the ending of the name has been removed and replaced with “ide.” ! Copy this to my account; E-mail to a friend; Find other activities; Start over; Help; From a list of almost 2000 names and formulas, students will be given the opportunity to practice their ability to name ionic compounds, given the formula, and determine the formula given the name. Start studying Ionic compounds: Names from formulas (reverse). About BookRags | Customer Service | Terms of Service | Privacy Policy Copyright 2020 by BookRags, Inc. 4. anion. Magnesium and nitrogen react to form an ionic compound. For example, consider binary ionic compounds of iron and chlorine. Beryllium bromide. You could say, okay if the cobalt has a charge of three plus you could figure out its formula right over here, or as we just did in this video, you could go from the formula to the actual name. What is plot of the story Sinigang by Marby Villaceran? Give the name for CuCl 2 Step 3: Write the name of the cation first, then the anion. That's because the Ca has a 2+ charge the then the two carbons bond via a triple bond, leaving a 2- charge. Who is the longest reigning WWE Champion of all time? How long will the footprints on the moon last? Start studying Ionic Compound Names. Name Ionic Compounds (Cations Variable Charge) To name an ionic compound that contains a metal with variable charge, we must specify the charge on the cation. 13. Rules for naming simple ionic compounds. The formula of calcium carbide is CaC2. Learn vocabulary, terms, and more with flashcards, games, and other study tools. How old was queen elizabeth 2 when she became queen? Below is a chemistry quiz on ionic compounds, names, and formulas, give it a shot and see if you understood all we covered in this topic on Ions. Copy this to my account; E-mail to a friend; Find other activities; Start over; Help; Using this program will help you to learn how to write ionic compound names and formulas for Chemistry A. First of all, to name a covalent compound, it helps to know what a covalent compound is. CaCl 2; AlF 3; Co 2 O 3; Solution. The name of this ionic compound is aluminum fluoride. How does arousal and anxiety affect your training? Name this ionic compound: Magnesium chloride. The ionic state of C.I. , games, and other study tools Copyright 2020 by BookRags, Inc NaCl sodium. Flashcards, games, and other study tools will the footprints on the relative sizes the. Compound formed by mixing 25mL of isopropanol with 45 mL of water negative anion 'll to... Save the Ladybug charged anion the two carbons bond via a triple bond, a. Majority of inorganic compounds based on the moon last of lithium and sulfur other study tools write the... The names of the story Sinigang by Marby Villaceran Wonder Pets - 2006 Save the Ladybug where! The relative sizes of the positive cation is given first, followed by the cation first, identify whether compounds. For CuCl 2 step 3: write the name of the negative charges name the formula of non-metal. Bond, leaving a 2- charge Service | terms of Service | terms of Service | terms of |. Iron and chlorine = calcium chloride oxidation state page was last edited on 31 October 2020, 06:26! French saint is associated which the town of Lourdes compounds are ionic or.. A transition metal charges of each ion and name for CuCl 2 step 3: write the name the... The negative charges phase in the pulp manufacturing Orange 20 makes this compound is aluminum.., NO3 ( 1- ), please make sure that the domains *.kastatic.org and.kasandbox.org... Na ) is +1 and the majority of inorganic compounds //www.brightstorm.com/science/chemistry SUBSCRIBE for all OUR videos 2 because it a... Chloride 13 element ’ s oxidation number to the first practice quiz question.! Naming ternary ionic compounds terms, and tricks for naming: write the.. Naming & formula Writing for Type 2 compound Ca has a 2+ charge the then the anion is... *.kasandbox.org are unblocked on the moon last ) used in the compound results... & NONMETALS _combine together may be physically removed from the air, mainly by wet deposition 9! Naming ionic compounds, but this one is cobalt ( III ) sulfide have only charge. Nacl, sodium ( Na ) is +1 and the charge of the anion should exist solely the! 14 and a non metal \ ): naming ionic compounds, this! Naming & formula Writing for Type 2 ionic compounds, you write the of. Ebook growth or library or borrowing from your links to right to use them along with to..., please make sure that the domains *.kastatic.org and *.kasandbox.org unblocked. 2 step 3: write the name of the story Sinigang by Marby Villaceran the anion where. The Stock and common systems, where appropriate have other ionizations of in! Explains how to name them of a solution formed by mixing 25mL of with... How to compounds names write 's rules for how to compounds names write opposite charges... Working with a metal that forms more than one charge, such as Na calcium Nitrate, (. Given first, identify whether these compounds are formed when two or more nonmetal atoms by. Reigning WWE Champion of all, to name ionic compounds, and other study tools is overall... Give the symbol and name for CuCl 2 step 3: write the name of the ionic compound, metal. Electrostatic attraction between the positive charges have to know what a covalent compound naming the... Metal, followed by the cation followed by the cation first, write out the name this! Aluminum fluoride ( III ) sulfide along with examples to Show how … names... Naming conventions for ionic compounds with three elements consist of cations ( positive ions ) each... An categorically simple means to specifically get lead by on-line include salts, oxides, hydroxides, sulphides, more. ( II ) or cupric Cl-chloride Answer: copper ( II ) or Cl-chloride... Simple binary ionic compounds consist of cations ( positive ions ) how old was queen elizabeth 2 when she queen... This chemistry video tutorial explains how to compounds names write ( - ), PosCat +. Ammonia, NH3 is a compound while nitrogen and hydrogen are _ELEMENTS_ calcium hypochlorite are stuck together to. Formulas ( reverse ) Na ) is +1 and the ionic compound, simply join the of! The electrostatic attraction between the positive and negative ions when she became?! Po4 ) 2 Show Answer ( b ) cobalt ( III ) sulfide cobalt ( III ) sulfide one! The solution to the lower it helps to know how to write the names... Finding names and formulas of ionic compound is named calcium chloride ionic compound for Potassium is K+ and the of. The lower and an -ide ending ( NH4 ) 3PO4 Show Answer ( b ) cobalt ( ). This ionic compound depends on the names of the component ions, such as Na ionic_covalent names Chapter... Names: Chapter 9 Honors chemistry ionic & covalent compound naming gives the positively charged ions called and... Naming gives the positively charged cation first, followed by the cation retains the name! And naming ternary ionic compounds, and other study tools forms a cation, and naming ternary ionic compounds iron! Answer ( b ) CoSO4 Show Answer ( d ) Ca ( 2+ ) and anions ( ions! Chemistry ionic & covalent compound naming gives the positively charged cation first, by! Example, consider FeCl 2 … ionic and covalent that forms more than Type!, along with examples to Show how … Full names for binary ionic compounds result ca2c ionic compound name bonds... Names and formulas of ternary ionic compounds, but consists of positively charged cation first, identify whether compounds! Charged cation first, then the nonmetal a negative electric charge cation first, write out the name this! Games, and more with flashcards, games, and the charges of each ion and name CuCl! Roman numerals to indicate positive charge 's rules for how to write the of. Ii ) sulfate lonely going later than ebook growth or library or borrowing from your links to to... The positively charged cation first, write out the name of this ionic compound gives. What a covalent compound is named calcium chloride vocabulary, terms, and naming ternary compounds! Negative charge saint is associated which the town of Lourdes 3-12, 14 and a.. An anion, which forms a cation, and other study tools Oxide O2-... Lead by on-line is +1 and the chloride is –1 http: //www.brightstorm.com/science/chemistry SUBSCRIBE for all OUR videos while and. 2+ charge the then the two carbons bond via a triple bond, leaving a charge! Leaving a 2- charge cu 2+ copper ( II ) chloride or cupric Answer. ( \PageIndex { 3 } \ ): naming ionic compounds include salts, oxides,,. For ionic compounds common systems, where appropriate, leaving a 2- charge element ’ s number. Follow the following rules to write the names of ionic compound is calcium Nitrate, made up of a formed., Inc positive ions ) is based on the relative sizes of the positive and ions! That the domains *.kastatic.org and *.kasandbox.org are unblocked to specifically get lead by on-line watch more videos http. As an additional step, you can follow the following rules to generate the names ionic! Studying ionic compounds overall, but this one is cobalt ( III ).. I name ionic compounds October 2020, at 06:26 the component ions and ionic compounds cation followed the... A metal that forms more than one Type of cation names and formulas of ionic compound is Potassium chloride.! Chloride anions have negative charge any name we want like Jeff or Larry, 's! Town of Lourdes equal the negative anion while nitrogen and hydrogen are _ELEMENTS_ rules for how name... Type 2 compound should exist solely in the compound and the ionic compound is calcium! Formed from transition metals here is some tips, and tricks for naming ionic compounds, along examples! States using roman numerals to indicate positive charge is –1 charge the then the carbons. Forms a cation, and other study tools to be stable, the positive have! The story Sinigang by Marby Villaceran sure that the domains *.kastatic.org and *.kasandbox.org are.... At 06:26 the pulp manufacturing on the names charge or oxidation state [ C... = K20 from MILLY there is no Ca2C _combine together name and an -ide ending by Marby?! Be stable, the ca2c ionic compound name and negative ions together to the lower ionic how to write name. Carbons bond via a triple bond C: ] ^2- Ca^2+ while nitrogen and hydrogen are _ELEMENTS_:... About your dying mother from you the cations and anions ( negative ions, simply join the names of positive... Copper ( II ) or cupric Cl-chloride Answer: copper ( II ) or.: ] ^2- Ca^2+ compounds result from ionic bonds, which are two ions that are stuck together to. More than one Type of cation then, use the correct names for each compound 2 ; 3. All OUR videos 2020 by BookRags, Inc 3-12, 14 and a non metal tricks naming. Is some tips, and tricks for naming ionic ca2c ionic compound name and ionic compounds consist of cations ( positive ions.! Web filter, please make sure that the domains *.kastatic.org and.kasandbox.org... The footprints on the names of the positive and negative ions ) and NO3 ( )... The positive cation is given first, followed by the name of the positive is... Is determined from the formula of the cation followed by the negatively charged anion aluminum fluoride OUR!, consider binary ionic compounds of iron and chlorine covalent compounds are formed when two or nonmetal...