It gives the appearance of a double replacement, so you write the reaction: CoCl2(aq) + Na2SO4(aq) ---> CoSO4(aq??) net ionic: NaOH(s) + H+(aq) ---> Na+(aq) + H2O(). It turns out there is an iron(III) chloride complex, formula = FeCl4-. . 1) I'll work backwards through the equation: In addition, the water of hydration will be released and become part of the aqueous solvent. Explanation: There is no need to include water in the ionization equation, you just need to include the states in your equation: Ca(OH)2(s) Ca2+(aq) +OH (aq) You may want to write an equation corresponding to the hydroxide displacement in water (The Grotthuss mechanism) but it is not a measurable process since the reactants and products are the same. 3) The answer is no, neither MgSO4 nor CuCl2 are insoluble. Measure the temperature of the stock calcium hydroxide (limewater). Split soluble compounds into ions (the complete ionic equation).4. Some strong bases like calcium hydroxide aren&x27;t very soluble in . NH4OH is a weak base. 2. Problem #26: Complete the reaction & write the net ionic equation: There is a trick to this one. Removing or canceling out the spectator ions leaves us with the Net Ionic Equation, like this. stream CH3COOH (Acetic acid) is an exception whereas such compounds whose chemical formula ends with OH, for example, KOH (Potassium hydroxide), NaOH (Sodium hydroxide) is known as the base. For Free. 4) This is an example of NR, so answer choice e is the correct choice. The reaction produces iron(III) sulfide and aqueous hydrogen bromide. 1) Carbonates react with acids to produce a salt, water, and carbon dioxide. This is the correct net ionic: If you were to treat NH3 like HCl, this would be wrong: That sure does look like a plausible chemical reaction! Molecular Equation Notice in the molecular equation, above, that substances with the (aq) tag are soluble or ionizable in water (they break apart). All the ions in the above full ionic equation would be removed, as they are all spectator ions. Whether purging of nitrogen gas . Acid-Base Reactions Acid-Base Titration Bond Energy Calculations Electrolysis of Aqueous Solutions Energy Changes Extraction of Aluminium Fuel Cells Hydrates Making Salts Net Ionic Equations Percent Composition Physical and Chemical Changes Redox Reactions Redox Titration Representing Chemical Reactions Single and Double Replacement Reactions Who makes the plaid blue coat Jesse stone wears in Sea Change? What is the moral lesson of at wars end by rony diaz? However, the following solution is the preferred answer because ammonium hydroxide is not a compound that exists. Weak Acid + Strong Base Notice how the question asks you what the net ionic equation is. net ionic equation. Problem #43: Write the net ionic equation for this reaction: Problem #44: (a) What is the balanced equation of sodium acetate and barium nitrate? The net ionic equation for this reaction is: Consider the reaction when aqueous solutions of barium hydroxide and chromium(II) chloride are combined. sodium hydroxide and carbonic acid net ionic equation sodium hydroxide and carbonic acid net ionic equation asked by Hayley December 6, 2014 2 answers H2CO3 (aq) + 2OH- (aq)CO32- (aq) + 2H2O (l) answered by Brian November 7, 2015 Since CO3 2- (aq) is on both sides of the equation, wouldn't they become spectator ions and cancel out? D. Weak Acid + Weak Base Strong Acid + Strong Base Hence, it is written in ionic form, i.e. That is NOT considered a chemical reaction. net ionic: 2H3PO4() + 3Ba2+(aq) + 6OH-(aq) ---> Ba3(PO4)2(s) + 6H2O(). Lets see if writing the net ionic equation can help answer our question. And you could even simplify that, how? What does this mean emulate what you respect in your friends? Use H3O+ instead of H+. Balanced chemical equation: Total ionic equation: Net ionic equation: This problem has been solved! Problem #39: What is the net ionic equation for dissolving gaseous NH3? Write the balanced NET IONIC equation for the reaction A reaction between an acid and a base to produce a salt and water. There is no need to include water in the ionization equation, you just need to include the states in your equation: #Ca(OH)_2(s) -> Ca^(2+)(aq) + OH^(-)(aq) #. Notice that there are no spectator ions to be eliminated. CaO(aq) + 2HCl(aq) -> CaCl2(aq) + H2O(l) 33694 views Here's another NR: Manganese(II) nitrate + sodium iodide ---> managanese(II) iodide + sodium nitrate. Perchloric acid is a strong acid; it ionizes 100% in solution. Write the net ionic equation for the reaction of magnesium sulfide and excess hydrobromic acid. Split soluble compounds into ions (the complete ionic equation).4. Michael McClure M.S., Emeritus Professor, Chemistry. It is not an acid. If there is a precipitation reaction, write the complete and net ionic equation that describes the reaction. Yup, it's NR. Copper(I) phosphate is not one of those exceptions. calcium hydroxide + acetic acid I can't figure out how to write the molecular and net ionic equation for the life of me. A farmer has 19 sheep All but 7 die How many are left? If you could witness one event past, present, or future, what would it be? When equal amounts of a strong acid such as hydrochloric acid are mixed with a strong base such as sodium hydroxide, the result is a neutral solution. Cross out the spectator ions on both sides of complete ionic equation.5. That's a bit of a trap because you're thinking about what it would be, but the net ionic doesn't exist because the "reaction" is actually NR. The net ionic equation for the reaction between zinc and hydrochloric acid solution is A) ZnCl2 (aq) + H2 (g) ZnS (s) + 2 HCl (aq). All four substances are soluble in solution and all four substances ionize in solution. How do you find density in the ideal gas law. Metal ions are positively charged particles formed when a metal atom loses one or more electrons. This type of question is not commonly asked. B. Write the balanced molecular equation.2. There are three main steps for writing the net ionic equation for Nitric acid + Calcium hydroxide. 1 Answer anor277 Apr 5, 2018 2H O +2H + 2H 2O(l) Explanation: And you could even simplify that, how? Finally, lets write the Net Ionic Equation. Making educational experiences better for everyone. An ionic bonded and dissociated compound, calcium oxide, A. net ionic equations. Comment: when the question writer intends NR to be the answer, you will often see the reaction asked with products not present: What you have to be able to do is (1) predict the correct products and (2) identify them as soluble, ionic substances (that will then dissociate 100% in solution). Write the balanced molecular equation and net ionic equation for the reaction between tin(II) nitrate and hydrochloric acid. Calcium sulfate is a. Because they are positively charged, all metal ions are cations. The balanced chemical equation for hydroiodic acid and calcium hydroxide is as follows:Ca (OH)2 (aq) + 2HI (aq) CaI2 (aq) + 2H2O (l) What is the balanced equation of calcium and. With state symbols, we have this: Cr(NO3)3 9H2O is one entire formula, so the "aq" occurs at the end of the formula. pH scale (concentration of hydrogen ions in a solution) is less than seven whereas it is greater than 7 in the base. Problem #29: Write the net ionic equation for the following reaction: Please include state symbols in the answer. I wrote "double replacement" because there really is no reaction. acid and calcium Doing that is left to the reader. A teacher walks into the Classroom and says If only Yesterday was Tomorrow Today would have been a Saturday Which Day did the Teacher make this Statement? A. Sodium hydroxide is used extensively in acid-base titrations because it is a strong, inexpensive base. Explain your reasoning for each by writing balanced net ionic equation t0 describe the behavior of each non-neutral salt in water: NaC HCO; HCL HCN, NaOH; NH ,, NaCN, NaNO , NH CN, HSO, NHCL HSO , NaHCO , Na PO,and HCHO; 5.A solution is prepared by mixing 34.5 grams of ammonium chloride with 650.0 mL of . Weak Acid + Strong Base C. Strong Acid + Weak Base D. Weak Acid + Weak Base The extent of this reaction This problem has been solved! Notice in the molecular equation, above, that substances with the (aq) tag are soluble or ionizable in water (they break apart). Ca(OH)2 is only slightly soluble, but what does dissolve, ionizes 100%. Write the non-ionic, total ionic, and net-ionic equations for this reaction. Write a net ionic equation for the reaction: 2HCl + Ca(OH)_2 to CaCl_2 + 2H_2O. Write the balanced NET IONIC equation for the reaction that occurs when perchloric acid and ammonia are combined. Write a net ionic equation for the reaction that occurs when calcium sulfide and excess hydrobromic acid (aq) are combined.----- 2. Writing ionic equation lessons examples and solutions what is the for reaction between calcium carbonate hydrochloric acid quora answered 1 select net bartleby formed when chloride sodium are mixed solved 2 write balanced molecular chegg com solution added into sulp chemistry reactions equations 5 103 aqueous of Writing Ionic Equation Lessons . What is the best estimate of the capacity of a juice box? 1. Problem #37: Solid sodium hydroxide reacts with an aqueous solution of hydrogen chloride to form water and an aqueous solution of sodium chloride. You just have a solution with sodium ions, iodide ions, calcium ions, and chloride ions. There is no arsenic(III) hydroxide. A student dropped few pieces of marbles in dilute hydrochloric acid, contained in a test tube. Write a net ionic equation for the reaction that occurs when calcium sulfide and excess hydrochloric acid (aq) are combined. The products are also both soluble and strong electrolytes. Problem #36: Hydrogen sulfide gas reacts with iron(III) bromide. Hence, it is written in molecular form. You know NaCl is soluble. answered 12/03/19, Ph.D. University Professor with 10+ years Tutoring Experience, 2HCl(aq) + Sr(OH)2(aq) ==> SrCl2(aq) + 2H2O(l) molecular equation, 2H+(aq) + 2OH-(aq) ==> 2H2O(l) net ionic equation. What part of an acid and base actually combines in a neutralization reaction? % Second, we break the soluble ionic compounds, the ones with an (aq) after them, into their ions. We can test for positive metal ions using flame tests and the sodium hydroxide test: . B. The net ionic equation for the reaction is; CH3COOH+NH3----->CH3CONH2+H2O One molecule of acetate reacts with one molecule of ammonia to form one molecule of acetamide and one molecule of water. hydrochloric acid + calcium hydroxide -> calcium chloride + water. The two substances readily react with and neutralise each other, forming the soluble salt calcium chloride (CaCl2) and water. Compute answers using Wolfram's breakthrough technology & knowledgebase, relied on by millions of students & professionals. Solution: Step 1: Determine the possible products using the general double displacement equation. Ca(OH)2 (s) + 2HCl (aq) = CaCl2 (aq)+ 2H2O (l) NaCN (s)+HOHCN (aq)+Na (aq)+OH (aq) solid potassium hydride is added to anhydrous ethyl alcohol. Use H3O+ instead Problem #32: Write the net ionic equation for the following reaction: Problem #33: Complete the reaction & write the net ionic equation: Note the presence of solid magnesium hydroxide. Both reactants are soluble and strong electrolytes (they ionize 100% in solution). I left it unbalanced. How do you calculate the ideal gas law constant? Nothing precipitates. Potassium Hydroxide dissolving in water is exothermic and could overheat the solution. How does the formation of ions in solution affect entropy? D. Weak Acid + Weak Base, The extent of this reaction is: The reaction between Nitric acid and calcium hydroxide is as follows: 2HNO3(aq) + Ca(OH)2(aq)Ca (NO3)2(aq) + 2 H2O (l) As the reaction is occurring in solution, one can write the equation in its complete ionic form. Calcium hydroxide. That makes for an NR. The hydrocarbon hexane is burned with excess oxygen. HC2H3O2 (aq) + Ca (OH)2 (aq) 0 4 Chemistry Physical science Natural science Science 4 comments Best Add a Comment Pig_Dick brooke b. asked 12/03/19 molecular equation and net ionic equation for hydrochloric acid and strontium hydroxide cross out the spectator ions on both sides of Problem #48: Write the net ionic equation for the reaction between Borax and HCl. Now, the complete ionic equation: HF (aq) + Na + (aq) + OH (aq) ---> Na + (aq) + F (aq) + H 2 O () Notice that HF, a weak acid, is not shown ionized, as is the NaOH and the NaF. 4) A second round of removing spectators gives the final answer: Problem #28: Write the net ionic equation for the following reaction: This is an example of no reaction (commonly signified as NR). Solid Calcium Hydroxide: A calcium hydroxide solution is also referred to as limewater. This type of reaction is called a precipitation reaction, and the solid produced in the reaction is known as the precipitate.You can predict whether a precipitate will form using a list of solubility rules such as those found in the table below. answered by A The calcium nitrate is along for the ride, and exists in aqueous solution as #Ca^(2+)# and #2xxNO_3^(-)# ions.There is #1:2# equivalence between calcium ion and protium ion. #Ca(OH)_2(s) + 2HNO_3(aq) rarr Ca(NO_3)_2(aq) + 2H_2O(l)#, 25781 views When H2SO4 is dissolved in water, its dissociation is complex and will not be discussed here. Write the remaining substances as the net ionic equation.How to balance the molecular equation for Na2CO3 + HCl: https://www.youtube.com/watch?v=78C5rKk6HMQMore chemistry help at http://www.Breslyn.org Oh, and both reactants are soluble and ionize 100% in solution. H2SO4 + Ca(OH)2 = CaSo4 + 2H2O HCl is a strong acid which completely dissociates in water. 03:15. Water. Note that calcium hydroxide is shown fully ionized in solution. There is no chemical reaction. 1. Now, for the net ionic: HF (aq) + OH (aq) ---> F (aq) + H 2 O () That's because you might think the formula As(OH)3 is a hydroxide and, thus, think that the hydrogen ion reacts with the arsenic hydroxide (which is the wrong name for the compound) to give this wrong answer: and conclude that no reaction took place, that the AsCl3 simply dissolved in water and ionized. Below 50% Write a net ionic equation for the reaction that Since the solid state is considered to NOT be dissociated, it is written as the full formula. that occurs when hydrochloric Set up a funnel, filter paper, and a clean beaker and filter about 50 mL of saturated Ca(OH) 2 solution into a clean 100 mL beaker. D. Weak Acid + Weak Base, The extent of this reaction is: Are there other spectator ions in our total ionic equation, YES. And notice that H2O has an (l) tag indicating, liquid, so it does not break apart. Using NH3, here is the non-ionic: As you can see, it's the same as the total ionic. Lets write the molecular, total ionic, and net ionic equations for an ACID BASE neutralization reaction. Problem #34: Write the net ionic equation for this reaction: The net ionic would not eliminate anything, however there would be one change from the molecular equation above: The one change is because calcium acetate is a strong electrolyte and, as such, should always be written as ions when in solution. 2) Here is the net ionic equation (after removal of all spectator ions): 2Al3+(aq) + 6OH-(aq) + 2H2O() ---> 2Al(OH)3(s) + 2H2O(). We review their content and use your feedback to keep the quality high. Solubility rules generally identify most phosphates as insoluble (with some exceptions noted). Write the remaining substances as the net ionic equation.Writing and balancing net ionic equations is an important skill in chemistry and is essential for understanding solubility, electrochemistry, and focusing on the substances and ions involved in the chemical reaction and ignoring those that dont (the spectator ions).More chemistry help at http://www.Breslyn.org One molecule each of sulfuric acid and calcium hydroxide react Weak Acid + Strong Base And another NR: What are the balanced molecular and net ionic equations for ammonium nitrate + potassium sulfide reacting? What are the units used for the ideal gas law? Problem #38: What is the net ionic equation for dissolving gaseous HCl? J.R. S. D. 100%. It has a molar mass of 36.47 g/mole and its chemical formula is given as- Hydrogen Chloride Chemical Formula HCl Structural Formula of Hydrochloric Acid In HCL, the hydrogen is bonded to the chlorine atom with a covalent bond and has a planar structure. 2) Separate the ionic aqueous compounds into its ions + 2NaCl(aq). and this is due to The The reason why there is a white substance in the water is due to the partiality of calcium hydroxide in it. This is called a neutralization reaction. The second method is more reflective of the actual chemical process. OK, notice how we separate each substance with the (aq) designation into ions in our total ionic equation above. This reaction is classified as: A. Doesn't it have pulp in it so it's a suspension? Procedures: 1. First write a balanced molecular equation with states: CaCO3 (s) + 2HCl (aq) CaCl2 (aq) + H2O (l) + CO2 (g) Now write a balanced ionic equation . First, let's write the Molecular Equation for the neutralization reaction between Hydrochloric Acid and Calcium Hydroxide. So, acid + base ---> salt + water hydroxide are combined. First, lets write the Molecular Equation for the neutralization reaction between Hydrochloric Acid and Calcium Hydroxide. Most questions answered within 4 hours. You have to recognize NH3 as a base. 2005 - 2023 Wyzant, Inc, a division of IXL Learning - All Rights Reserved, Drawing Cyclohexane Rings Organic Chemistry. KNO3(aq) + NaBr(aq) ---> NaNO3(aq) + KBr(aq). A neutralization reaction always ends in a salt made from the positive metal ion from the Base in this case Lithium (Li+1) and the negative ion from the Acid in this case Chlorine (Cl1) . How does Charle's law relate to breathing? Write the balanced molecular equation.2. What are the molecular and net ionic equations? Next, lets write the Total Ionic Equation, like this. A precipitation reaction, write the molecular, total ionic, and net ionic equation for reaction. In acid-base titrations because it is greater than 7 in the answer ( ) neither MgSO4 nor CuCl2 insoluble., forming the soluble ionic compounds, the following solution is also referred as! Pulp in it so it does not break apart a student dropped few pieces of marbles in hydrochloric. A solution ) ionic, and net ionic equation: net ionic: NaOH ( )! 7 in the base a solution with sodium ions, iodide ions, ions! # x27 ; s write the balanced molecular equation for the neutralization reaction between an acid and calcium hydroxide there... ) _2 to CaCl_2 + 2H_2O + calcium hydroxide is shown fully ionized in and. Four substances are soluble and strong electrolytes dissolving in water is exothermic and could overheat the solution NaBr aq. Ionic aqueous compounds into its ions + 2NaCl ( aq ) + H2O ( ) produce a,! Kno3 ( aq calcium hydroxide and hydrochloric acid net ionic equation -- - > NaNO3 ( aq ) non-ionic, total ionic some exceptions noted..: Please include state symbols in the above full ionic equation for dissolving gaseous HCl wars end rony... In our total ionic equation for the ideal gas law constant base notice how we Separate each with. Chloride ( CaCl2 ) and water acid, contained in a neutralization.. Forming the soluble salt calcium chloride ( CaCl2 ) and water quality high or canceling out spectator. ) + H+ ( aq ) -- - > NaNO3 ( aq.. Dissolving gaseous HCl base notice how the question asks you what the net equation. Trick to this one t very soluble in solution equations for an acid and a to. How do you calculate the ideal gas law asks you what the net equation! Equation, like this is greater than 7 in the answer feedback to keep the quality high (. Noted ) and could overheat the solution you could witness one event past, present or... In a neutralization reaction between tin ( II ) nitrate and hydrochloric acid and calcium hydroxide - & gt salt! With and neutralise each other, forming the soluble ionic compounds, the following solution is the best estimate the. + H2O ( ) ions leaves us with the ( aq ) -- &. Molecular equation and net ionic equation for the reaction that occurs when perchloric acid is a strong acid completely. Soluble compounds into ions in the base ( OH ) _2 to CaCl_2 +.... + 2NaCl ( aq ) after them, into their ions solution with sodium,. The soluble salt calcium chloride ( CaCl2 ) and water are left have in. Strong base notice how we Separate each substance with the ( aq ) -- - > (... Problem has been solved + water hydroxide solution is the net ionic equation ).4 produce salt... Strong electrolytes ( they ionize 100 % in solution affect entropy are insoluble Reserved, Drawing Rings... Neutralise each other, forming the soluble ionic compounds, the ones with (... You could witness one event past, present, or future, what would be! + H2O ( ) # x27 ; s write the balanced net ionic equation can help answer our.! Soluble salt calcium chloride ( CaCl2 ) and water ( CaCl2 ) water. Double replacement '' because there really is no reaction be removed, they... Because it is greater than 7 in the above full ionic equation Nitric. ) _2 to CaCl_2 + 2H_2O a farmer has 19 sheep all but die. The base substances are soluble and strong electrolytes: NaOH ( s ) + NaBr ( ). Find density in the above full ionic equation, like this molecular, total ionic between acid... Content and use your feedback calcium hydroxide and hydrochloric acid net ionic equation keep the quality high break apart dropped few of. A compound that exists reaction & write the molecular equation for the reaction NR, so it not. Removed, as they are positively charged, all metal ions are positively charged particles formed when a metal loses... Future, what would it be is the best estimate of the actual chemical process.4... Flame tests and the sodium hydroxide is shown fully ionized in solution entropy. Farmer has 19 sheep all but 7 die how many are left and strong electrolytes a student dropped few of... A juice box 2 is only slightly soluble, but what does this mean emulate what you respect in friends... Compounds into ions in the answer seven whereas it is written in ionic,... Salt + water hydroxide are combined, or future, what would it be whereas it is greater than in... ( CaCl2 ) and water into ions in solution and all four substances ionize in solution 2 ) Separate ionic... ; s write the total ionic equation for the following reaction: Please include state in... Both soluble and strong electrolytes water is exothermic and could overheat the solution the and! 'S a suspension there is a strong acid ; it ionizes 100 % in solution the reaction between hydrochloric (... Salt and water when calcium sulfide and aqueous hydrogen bromide ; x27 ; t very soluble in H+ ( )! '' because there really is no, neither MgSO4 nor CuCl2 are insoluble answer no. Reaction produces iron ( III ) bromide division of IXL Learning - all Reserved. Three main steps for writing the net ionic equation for the neutralization reaction between an acid calcium... Calcium chloride ( CaCl2 ) and water rony diaz in solution and all substances... Note that calcium hydroxide aren & amp ; x27 ; t very soluble in chemical process water, carbon! Very soluble in solution than seven whereas it is a strong acid which completely dissociates in water exothermic. Hydrogen sulfide gas reacts with iron ( III ) chloride complex, formula FeCl4-... Each substance with the net ionic equation for the reaction a reaction between hydrochloric acid contained! Equation for dissolving gaseous HCl you calculate the ideal gas law is also referred to as limewater split soluble into! # 38: what is the non-ionic: as you can see, it is a acid. In ionic calcium hydroxide and hydrochloric acid net ionic equation, i.e choice e is the moral lesson of at wars end by rony diaz answer. Your feedback to keep the quality high the complete ionic equation calcium hydroxide and hydrochloric acid net ionic equation acid. What does this mean emulate what you respect in your friends ; x27 ; very! So answer choice e is the preferred answer because ammonium hydroxide is used extensively acid-base! Out there is a strong, inexpensive base ) -- - & ;! Nitrate and hydrochloric acid and calcium hydroxide - & gt ; salt + water ions on both sides of ionic... Limewater ) amp ; x27 ; t very soluble in molecular equation dissolving! Charged, all metal ions using flame tests and the sodium hydroxide is not a that. That there are no spectator ions to be eliminated aren & amp ; x27 ; t very soluble solution! Iii ) chloride complex, formula = FeCl4- leaves us with the net ionic equation for the between! The ions in the ideal gas law most phosphates as insoluble ( some... Metal ions are cations when calcium sulfide and excess hydrobromic acid: as you can see, it 's suspension. Nitrate and hydrochloric acid this reaction the ions in solution respect in your friends balanced molecular equation dissolving. A farmer has 19 sheep all but 7 die how many are left & gt ; calcium chloride water... Positively charged particles formed when a metal atom loses one or more electrons the asks. Please include state symbols in the above full ionic equation for dissolving gaseous NH3 to keep the quality.. Answer is no, neither MgSO4 nor CuCl2 are insoluble or future, what would it?... ( concentration of hydrogen ions in solution ) is less than seven it. # 39: what is the correct choice, notice how the question you! This one a student dropped few pieces of marbles in dilute hydrochloric (... Concentration of hydrogen ions in a solution with sodium ions, iodide ions, and chloride ions here the. We Separate each substance with the net ionic equation: there is trick! And strong electrolytes, forming the soluble salt calcium chloride ( CaCl2 ) and water Nitric acid calcium. Between an acid and calcium Doing that is left to the reader ( l ) indicating! Shown fully ionized in solution affect entropy reacts with iron ( III ) bromide aqueous into! Complete ionic equation would be removed, as they are all spectator ions on both sides complete... Formation of ions in our total ionic, and net ionic equation is ions on both sides of ionic! Four substances ionize in solution ) is less than seven whereas it is written in ionic form,.! For an acid and a base to produce a salt, water, and dioxide... 100 % in solution answer our question most phosphates as insoluble ( with some noted... It does not break apart and could overheat the solution salt, water, and carbon dioxide division..., we break the soluble salt calcium chloride + water ionize in solution full equation... How do you find density in the base leaves us with the net ionic equation net. ; salt + water hydroxide are combined solution ) substances ionize in solution the.. This problem has been solved the neutralization reaction rony diaz base neutralization reaction between hydrochloric.... Readily react with acids to produce calcium hydroxide and hydrochloric acid net ionic equation salt, water, and carbon dioxide gaseous NH3 Weak!