<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0187-893X</journal-id>
<journal-title><![CDATA[Educación química]]></journal-title>
<abbrev-journal-title><![CDATA[Educ. quím]]></abbrev-journal-title>
<issn>0187-893X</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional Autónoma de México, Facultad de Química]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0187-893X2024000300125</article-id>
<article-id pub-id-type="doi">10.22201/fq.18708404e.2024.3.87494</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Colores y números: extractos vegetales como indicadores de pH]]></article-title>
<article-title xml:lang="en"><![CDATA[Colors and numbers: natural extracts as pH indicators]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Corinaldesi]]></surname>
<given-names><![CDATA[Sofia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Intrieri]]></surname>
<given-names><![CDATA[Milena]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Abdala]]></surname>
<given-names><![CDATA[Florencia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gonzalez]]></surname>
<given-names><![CDATA[Laureana]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Salvai Destain]]></surname>
<given-names><![CDATA[Ailin]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Constenla]]></surname>
<given-names><![CDATA[Diana]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ciolino]]></surname>
<given-names><![CDATA[Andres]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Universidad Nacional del Sur Departamento de Ingeniería Química ]]></institution>
<addr-line><![CDATA[Buenos Aires ]]></addr-line>
<country>Argentina</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>00</month>
<year>2024</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>00</month>
<year>2024</year>
</pub-date>
<volume>35</volume>
<numero>3</numero>
<fpage>125</fpage>
<lpage>139</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0187-893X2024000300125&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0187-893X2024000300125&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0187-893X2024000300125&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen En este trabajo se reporta el uso de un indicador de pH obtenido a partir de la mezcla de algunos pigmentos orgánicos naturales. El indicador se propone como una herramienta económicamente accesible y medioambientalmente amigable para actividades de laboratorio que involucren conceptos como titulaciones ácido-base o escala de pH. La propuesta se presenta como un aprendizaje efectivo que une análisis cuali y cuantitativo, permitiendo cubrir diversos tópicos del currículum, tales como procesos de extracción, colorimetría, estadística y análisis de datos, indicadores naturales y escala de pH.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract A pH-indicator obtained from mixtures of natural pigments extracts is presented as an economically feasible and environmentally friendly laboratory activity. Optimal mixtures, with well-defined pH-ranges and colors for acid, neutral and basic media were observed. The work is presented as a hand-on activity that links qualitative &amp; quantitative analysis, and it is proposed as an efficient tool for covering several basics from curriculum, such as extraction processes, colorimetry, data &amp; statistics, natural indicators, and pH.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Química analítica]]></kwd>
<kwd lng="es"><![CDATA[Prácticas químicas]]></kwd>
<kwd lng="es"><![CDATA[Ácido-base]]></kwd>
<kwd lng="es"><![CDATA[Análisis de datos]]></kwd>
<kwd lng="es"><![CDATA[Escala de pH]]></kwd>
<kwd lng="es"><![CDATA[Métodos cuali y cuantitativos]]></kwd>
<kwd lng="en"><![CDATA[Analytical chemistry]]></kwd>
<kwd lng="en"><![CDATA[Chemical Practices]]></kwd>
<kwd lng="en"><![CDATA[Acid-base]]></kwd>
<kwd lng="en"><![CDATA[Data Analysis]]></kwd>
<kwd lng="en"><![CDATA[pH Scale]]></kwd>
<kwd lng="en"><![CDATA[Qualitative and Quantitative Methods]]></kwd>
</kwd-group>
</article-meta>
</front><back>
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<surname><![CDATA[Zhang]]></surname>
<given-names><![CDATA[Q-W]]></given-names>
</name>
<name>
<surname><![CDATA[Ye]]></surname>
<given-names><![CDATA[W-C.]]></given-names>
</name>
</person-group>
<article-title xml:lang=""><![CDATA[Techniques for extraction and isolation of natural products: a comprehensive review]]></article-title>
<source><![CDATA[Chin. Med.]]></source>
<year>2018</year>
<volume>13</volume>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
