Which of the following is a precipitation reaction?

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Presentation transcript:

Which of the following is a precipitation reaction? QUESTION: Which of the following is a precipitation reaction? A. Na2CO3(aq) + 2 AgNO3(aq)  Ag2CO3(s) + 2 NaNO3(aq) B. 2 Mg(s) + O2(g)  2 MgO(s) C. HCl(aq) + NaOH(aq)  NaCl(aq) + H2O(l) Precipitation: reaction in a liquid mixture formation of a solid product (insoluble in liquid) Which of the following is a precipitation reaction? A. Na2CO3(aq) + 2 AgNO3(aq)  Ag2CO3(s) + 2 NaNO3(aq) 2 Mg(s) + O2(g)  2 MgO(s) Or C. HCl(aq) + NaOH(aq)  NaCl(aq) + H2O(l) PAUSE CLICK A precipitation reaction occurs in liquid mixture and involves the formation of a solid product that is insoluble the liquid. Therefore, we can eliminate choice C. This reaction does not have a solid product. CROSS OUT Choice C Both choices A and B have a solid product. HIGHLIGHT Ag2CO3(s) and MgO(s) But choice B does not involve a reaction in a liquid mixture. SO choice B is wrong. CROSS OUT Choice B. The correct answer is choice A. Here, two aqueous solutions HIGHLIGHT Na2CO3(aq) and AgNO3(aq) … are mixed and a solid product… HIGHLIGHT Ag2CO3(s) … is formed. The solid product is called a precipitate. CALLOUT “Precipitate” pointing to Ag2CO3(s) PAUSE END RECORDING

Video ID: 5-6-1 © 2008, Project VALUE (Video Assessment Library for Undergraduate Education), Department of Physical Sciences Nicholls State University Author: Glenn V. Lo Narrator: Funded by Louisiana Board of Regents Contract No. LA-DL-SELECT-13-07/08