{"id":2169,"date":"2026-10-15T00:28:11","date_gmt":"2026-10-14T23:28:11","guid":{"rendered":"https:\/\/wpcalc.com\/pt\/quimica\/calculadora-energia-do-foton\/"},"modified":"2026-10-15T00:28:11","modified_gmt":"2026-10-14T23:28:11","slug":"calculadora-energia-do-foton","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/pt\/quimica\/calculadora-energia-do-foton\/","title":{"rendered":"Calculadora de energia do f\u00f3ton"},"content":{"rendered":"<section class=\"not-prose calculator-box\" aria-labelledby=\"calculator-title\"><div class=\"flex items-baseline sm:items-center justify-between gap-2 sm:gap-3\"><div class=\"flex flex-col sm:flex-row sm:items-center gap-2\"><span class=\"icon icon-calculator text-primary-700! text-base! dark:text-primary-300!\" aria-hidden=\"true\"><\/span><h2 id=\"calculator-title\" class=\"text-lg font-display font-bold\">Energia do f\u00f3ton a partir do comprimento de onda ou da frequ\u00eancia<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"2169\" data-favorite-title=\"Energia do f\u00f3ton\" data-favorite-url=\"https:\/\/wpcalc.com\/pt\/quimica\/calculadora-energia-do-foton\/\" data-favorite-excerpt=\"Calcule a energia de um f\u00f3ton a partir do comprimento de onda ou da frequ\u00eancia. Basta informar um dos dois valores para obter a energia por f\u00f3ton em joules e el\u00e9trons-volt, al\u00e9m da energia por mol de f\u00f3tons em kJ\/mol.\" aria-label=\"Adicionar aos favoritos\" data-favorite-icon=\"icon icon-spectrum\">\n    <span class=\"icon icon-shape-star-empty\" aria-hidden=\"true\"><\/span>\n  <\/button>\n  <div class=\"calcdash-favorite__tip\" aria-hidden=\"true\">\n   <span class=\"favorite-tooltip\" id=\"favorite-tooltip\"><\/span>\n  <\/div>\n  <span class=\"sr-only\" role=\"status\" id=\"favorite-status\"><\/span>\n<\/div><\/div><form action=\"https:\/\/wpcalc.com\/pt\/quimica\/calculadora-energia-do-foton\/\" method=\"POST\" class=\"calculator\" id=\"calculator-2169\" data-post=\"2169\"><fieldset class=\"fieldset-input is-2\"><legend class=\"sr-only\">Campos de entrada<\/legend><div class=\"field\" id=\"input-1\"><label for=\"field-1\">Tipo de entrada<\/label><div class=\"grid grid-cols-1\"><select id=\"field-1\" name=\"tipo_de_entrada\"><option value=\"wl\" selected>Comprimento de onda (\u03bb)<\/option><option value=\"fr\">Frequ\u00eancia (\u03bd)<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><div class=\"field is-single has-term\" id=\"input-2\"><label for=\"field-2\">Comprimento de onda (\u03bb)<\/label><div class=\"term\">\u03bb<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"text\" name=\"comprimento_de_onda_\" id=\"field-2\" aria-describedby=\"calc-info-2\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 500\" min=\"0\" value=\"500\"\/><div class=\"grid grid-cols-1\"><select id=\"field-3\" name=\"unidade\" aria-label=\"Unidade\"><option value=\"nm\" selected>nm<\/option><option value=\"um\">\u00b5m<\/option><option value=\"mm\">mm<\/option><option value=\"cm\">cm<\/option><option value=\"m\">m<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-2\">Comprimento de onda da luz no v\u00e1cuo.<\/small><\/div><div class=\"field is-single has-term\" id=\"input-3\" hidden><label for=\"field-4\">Frequ\u00eancia (\u03bd)<\/label><div class=\"term\">\u03bd<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"text\" name=\"frequncia_\" id=\"field-4\" aria-describedby=\"calc-info-4\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 600\" min=\"0\" value=\"600\"\/><div class=\"grid grid-cols-1\"><select id=\"field-5\" name=\"unidade\" aria-label=\"Unidade\"><option value=\"hz\">Hz<\/option><option value=\"khz\">kHz<\/option><option value=\"mhz\">MHz<\/option><option value=\"ghz\">GHz<\/option><option value=\"thz\" selected>THz<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-4\">Frequ\u00eancia da luz (ciclos por segundo).<\/small><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Recalcular\" id=\"calculate-button\" data-post=\"2169\">Calcular<\/button><button type=\"reset\">Redefinir<\/button><\/div><div class=\"field is-checkbox hidden!\" id=\"field-auto-calc\"><input type=\"checkbox\" id=\"auto-calc\"><label for=\"auto-calc\">Calcular automaticamente<\/label><small>Se ativado, o resultado \u00e9 atualizado automaticamente quando voc\u00ea altera qualquer valor.<\/small><\/div><div class=\"fieldset-result is-hidden\" aria-labelledby=\"result-title\" aria-live=\"polite\" role=\"region\"> <h3 class=\"result-title bg-gradient-to-r from-primary-50 to-gray-50 dark:from-primary-900 dark:to-gray-800\" id=\"result-title\"><span class=\"icon icon-s-pulse\" aria-hidden=\"true\"><\/span> Energia do f\u00f3ton<\/h3><div class=\"result-box\"><div class=\"field-result\" id=\"output-1\"><span class=\"field-title\"><span>Energia por f\u00f3ton<\/span><span class=\"result-term\">E<\/span><\/span><span class=\"field-value\" id=\"result-1\" data-unit=\"J\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copiar resultado\" aria-label=\"Copiar resultado\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><div class=\"field-result\" id=\"output-2\"><span class=\"field-title\"><span>Energia por f\u00f3ton<\/span><span class=\"result-term\">E<\/span><\/span><span class=\"field-value\" id=\"result-2\" data-unit=\"eV\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copiar resultado\" aria-label=\"Copiar resultado\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><div class=\"field-result\" id=\"output-3\"><span class=\"field-title\"><span>Energia por mol de f\u00f3tons<\/span><span class=\"result-term\">E\u00b7N_A<\/span><\/span><span class=\"field-value\" id=\"result-3\" data-unit=\"kJ\/mol\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copiar resultado\" aria-label=\"Copiar resultado\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><div class=\"field-result\" id=\"output-4\"><span class=\"field-title\"><span>Frequ\u00eancia<\/span><span class=\"result-term\">\u03bd<\/span><\/span><span class=\"field-value\" id=\"result-4\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copiar resultado\" aria-label=\"Copiar resultado\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><div class=\"field-result\" id=\"output-5\"><span class=\"field-title\"><span>Comprimento de onda<\/span><span class=\"result-term\">\u03bb<\/span><\/span><span class=\"field-value\" id=\"result-5\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copiar resultado\" aria-label=\"Copiar resultado\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><div class=\"field-result is-column\" id=\"output-6\"><span class=\"field-title\"><span>Detalhes do c\u00e1lculo<\/span><\/span><span class=\"field-value\" id=\"result-6\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copiar resultado\" aria-label=\"Copiar resultado\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><div class=\"field-result is-column\" id=\"output-7\"><span class=\"field-title\"><span>Sobre a energia do f\u00f3ton<\/span><\/span><span class=\"field-value\" id=\"result-7\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copiar resultado\" aria-label=\"Copiar resultado\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><\/div><div class=\"result-actions\"><button type=\"button\" class=\"copy-link\"><svg viewBox=\"0 0 20 20\" fill=\"currentColor\" aria-hidden=\"true\"><path d=\"M12.232 4.232a2.5 2.5 0 0 1 3.536 3.536l-1.225 1.224a.75.75 0 0 0 1.061 1.06l1.224-1.224a4 4 0 0 0-5.656-5.656l-3 3a4 4 0 0 0 .225 5.865.75.75 0 0 0 .977-1.138 2.5 2.5 0 0 1-.142-3.667l3-3Z\"\/><path d=\"M11.603 7.963a.75.75 0 0 0-.977 1.138 2.5 2.5 0 0 1 .142 3.667l-3 3a2.5 2.5 0 0 1-3.536-3.536l1.225-1.224a.75.75 0 0 0-1.061-1.06l-1.224 1.224a4 4 0 1 0 5.656 5.656l3-3a4 4 0 0 0-.225-5.865Z\"\/><\/svg><span class=\"copy-link__text\">Copiar link para este c\u00e1lculo<\/span><\/button><span class=\"sr-only\" role=\"status\" id=\"copy-link-status\"><\/span><\/div><\/div><a href=\"#respond\" class=\"hidden transition-opacity duration-300 opacity-0 w-50 text-sm justify-center items-center gap-2 px-4 py-2 rounded bg-gray-200 text-gray-700 hover:bg-gray-300\" id=\"leave-comment\"><span class=\"icon icon-comments\" aria-hidden=\"true\"><\/span>Deixar um coment\u00e1rio<\/a><\/form><\/section><section id=\"calc-reactions\" class=\"not-prose hidden my-12 bg-gradient-to-r from-primary-50 to-gray-50 border border-indigo-100 rounded-xl px-6 py-4 shadow-sm\" data-post=\"2169\" aria-live=\"polite\" aria-labelledby=\"calc-reactions-title\"><p id=\"calc-reactions-title\" class=\"text-sm text-gray-500 text-center mb-2\">O que voc\u00ea achou deste resultado?<\/p><div role=\"group\" aria-labelledby=\"calc-reactions-title\" class=\"grid grid-cols-3 sm:flex sm:flex-row sm:justify-around gap-4 sm:items-center sm:flex-wrap\"><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"like\"><span class=\"reaction-count\" data-reaction-count=\"like\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude00 <\/span><span class=\"reaction-description font-medium\">Curti <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"helpful\"><span class=\"reaction-count\" data-reaction-count=\"helpful\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\udca1 <\/span><span class=\"reaction-description font-medium\">\u00datil <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"confused\"><span class=\"reaction-count\" data-reaction-count=\"confused\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude15 <\/span><span class=\"reaction-description font-medium\">Confuso <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"disappointed\"><span class=\"reaction-count\" data-reaction-count=\"disappointed\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude1e <\/span><span class=\"reaction-description font-medium\">Decepcionado <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"inaccurate\"><span class=\"reaction-count\" data-reaction-count=\"inaccurate\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\u274c <\/span><span class=\"reaction-description font-medium\">Impreciso <\/span><\/button><\/div><div id=\"reaction-message\" class=\"hidden mt-8 rounded-md border border-primary-100 bg-white\/50 backdrop-blur-sm px-4 py-2 text-sm text-center shadow-sm\"><\/div><\/section><div class=\"calcdash-ad not-prose calcdash-ad--calc_result calcdash-ad--in-article\"><ins class=\"adsbygoogle\" style=\"display:block\" data-ad-client=\"ca-pub-1721569815777345\" data-ad-slot=\"6317458308\" data-ad-layout=\"in-article\" data-ad-format=\"fluid\"><\/ins><script>(adsbygoogle = window.adsbygoogle || []).push({});<\/script><\/div>\n<style id=\"wpcoderpro-inline-1\">.formula-box {\r\n\tborder-bottom: none !important;\r\n}<\/style><section class=\"formula-box\" aria-labelledby=\"formula-title\">\r\n\t<div id=\"formula-title\" class=\"not-prose font-display mb-4\"><span class=\"icon icon-formula\" aria-hidden=\"true\"><\/span><h2>Energia do f\u00f3ton<\/h2><\/div>\r\n\t<figure class=\"not-prose formula\">\r\n\t\t<figcaption class=\"formula-title\">F\u00f3rmula<\/figcaption>\r\n\t\t<div class=\"text-base text-gray-800\" id=\"formula\">\n\\[ E = h\\nu = \\frac{hc}{\\lambda} \\qquad \\nu = \\frac{c}{\\lambda} \\qquad E_{\\text{mol}} = E \\cdot N_A \\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Onde:<\/strong><\/p>\n<ul>\n<li>\\(E\\) \u2014 energia de um f\u00f3ton (J)<\/li>\n<li>\\(h\\) \u2014 constante de Planck, \\(6.62607015 \\times 10^{-34}\\) J\u00b7s (valor exato)<\/li>\n<li>\\(\\nu\\) \u2014 frequ\u00eancia da luz (Hz)<\/li>\n<li>\\(c\\) \u2014 velocidade da luz no v\u00e1cuo, \\(2.99792458 \\times 10^{8}\\) m\/s (valor exato)<\/li>\n<li>\\(\\lambda\\) \u2014 comprimento de onda no v\u00e1cuo (m)<\/li>\n<li>\\(N_A\\) \u2014 constante de Avogadro, \\(6.02214076 \\times 10^{23}\\) mol\u207b\u00b9 (valor exato)<\/li>\n<li>\\(E_{\\text{mol}}\\) \u2014 energia por mol de f\u00f3tons, tamb\u00e9m chamada de um einstein (J\/mol)<\/li>\n<\/ul>\n<p>Esta \u00e9 a rela\u00e7\u00e3o de Planck: a energia de um \u00fanico f\u00f3ton \u00e9 determinada inteiramente pela frequ\u00eancia (ou, de forma equivalente, pelo comprimento de onda) da luz, pois \\(\\lambda \\nu = c\\).<\/p>\n<p>\r\n<\/section>\n<style id=\"wpcoderpro-inline-2\">.calculation-box {\r\n\tborder-bottom: none !important;\r\n}<\/style><section id=\"calculation\" class=\"calculation-box\" aria-labelledby=\"calculation-title\">\r\n\t<div id=\"calculation-title\" class=\"not-prose font-display\"><span class=\"icon icon-unordered-list\" aria-hidden=\"true\"><\/span><h2>Energia do f\u00f3ton \u2013 Exemplo de c\u00e1lculo<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Exemplo:<\/strong> luz verde com comprimento de onda de 500 nm (o valor padr\u00e3o da calculadora).<\/p>\n<p>\\[ \\lambda = 500\\ \\text{nm} = 5.00 \\times 10^{-7}\\ \\text{m} \\]<\/p>\n<p>\\[ \\nu = \\frac{c}{\\lambda} = \\frac{2.99792458 \\times 10^{8}}{5.00 \\times 10^{-7}} = 5.996 \\times 10^{14}\\ \\text{Hz} \\approx 599.6\\ \\text{THz} \\]<\/p>\n<p>\\[ E = h\\nu = 6.62607015 \\times 10^{-34} \\times 5.996 \\times 10^{14} = 3.973 \\times 10^{-19}\\ \\text{J} \\]<\/p>\n<p>\\[ E = \\frac{3.973 \\times 10^{-19}}{1.602176634 \\times 10^{-19}} \\approx 2.48\\ \\text{eV} \\qquad E_{\\text{mol}} = 3.973 \\times 10^{-19} \\times 6.02214076 \\times 10^{23} \\approx 239\\ \\text{kJ\/mol} \\]<\/p>\n<p><strong>Resultado:<\/strong> cada f\u00f3ton de luz de 500 nm carrega \\(3.973 \\times 10^{-19}\\) J \u2248 2,48 eV, e um mol desses f\u00f3tons carrega cerca de 239 kJ. Esse valor est\u00e1 na regi\u00e3o verde do espectro vis\u00edvel.<\/p>\n<p>\n\r\n<\/section>\n<h2>Como usar a calculadora<\/h2>\n<ol>\n<li>No menu suspenso <strong>Tipo de entrada<\/strong>, selecione <strong>Comprimento de onda (\u03bb)<\/strong> ou <strong>Frequ\u00eancia (\u03bd)<\/strong>, dependendo da grandeza que voc\u00ea conhece.<\/li>\n<li>Se voc\u00ea escolheu o comprimento de onda, informe o valor no campo <strong>Comprimento de onda (\u03bb)<\/strong> e escolha a unidade (nm, \u00b5m, mm, cm ou m). Se escolheu a frequ\u00eancia, informe o valor no campo <strong>Frequ\u00eancia (\u03bd)<\/strong> e escolha a unidade (Hz, kHz, MHz, GHz ou THz).<\/li>\n<li>O painel de resultados mostra a <strong>Energia por f\u00f3ton<\/strong> em joules e el\u00e9trons-volt, a <strong>Energia por mol de f\u00f3tons<\/strong> em kJ\/mol, al\u00e9m do comprimento de onda ou da frequ\u00eancia complementar e do n\u00famero de onda em cm\u207b\u00b9.<\/li>\n<li>Consulte o painel <strong>Detalhes do c\u00e1lculo<\/strong> para ver o c\u00e1lculo passo a passo e o painel <strong>Sobre a energia do f\u00f3ton<\/strong> para saber mais sobre a regi\u00e3o espectral e valores de refer\u00eancia t\u00edpicos.<\/li>\n<\/ol>\n<h2>O que \u00e9 a energia do f\u00f3ton?<\/h2>\n<p>A luz se comporta tanto como onda quanto como um fluxo de part\u00edculas chamadas f\u00f3tons. Cada f\u00f3ton carrega um pacote min\u00fasculo e discreto de energia, cujo tamanho depende apenas da frequ\u00eancia da luz: frequ\u00eancia mais alta (comprimento de onda mais curto) significa f\u00f3tons mais energ\u00e9ticos. Essa \u00e9 a ess\u00eancia da rela\u00e7\u00e3o de Planck \\(E = h\\nu\\), a equa\u00e7\u00e3o que deu origem \u00e0 f\u00edsica qu\u00e2ntica em 1900 e que mais tarde rendeu a Einstein o Nobel pela explica\u00e7\u00e3o do efeito fotoel\u00e9trico.<\/p>\n<p>A energia de um \u00fanico f\u00f3ton \u00e9 extremamente pequena \u2014 da ordem de \\(10^{-19}\\) J para a luz vis\u00edvel \u2014 por isso costuma ser expressa em <strong>el\u00e9trons-volt (eV)<\/strong>, em que 1 eV \u00e9 a energia que um el\u00e9tron adquire ao atravessar uma diferen\u00e7a de potencial de 1 volt (\\(1\\ \\text{eV} = 1.602 \\times 10^{-19}\\) J). Os f\u00f3tons vis\u00edveis v\u00e3o de aproximadamente 1,6 eV (750 nm, vermelho) a 3,3 eV (380 nm, violeta); os f\u00f3tons ultravioleta s\u00e3o ainda mais energ\u00e9ticos, e os f\u00f3tons de raios gama chegam a milh\u00f5es de eV.<\/p>\n<p>Na qu\u00edmica e na fotoqu\u00edmica, a <strong>energia por mol de f\u00f3tons<\/strong> (um einstein) costuma ser a medida mais \u00fatil, pois permite comparar diretamente a energia do f\u00f3ton com as energias de liga\u00e7\u00e3o e de ativa\u00e7\u00e3o em kJ\/mol. Por exemplo, a luz ultravioleta de 254 nm entrega cerca de 471 kJ\/mol (o suficiente para romper muitas liga\u00e7\u00f5es covalentes), enquanto a luz vermelha de 700 nm entrega apenas cerca de 171 kJ\/mol, abaixo at\u00e9 mesmo das liga\u00e7\u00f5es simples O\u2013O mais fracas. \u00c9 por isso que a luz UV causa queimaduras solares e fotodegrada\u00e7\u00e3o, enquanto a luz vermelha em geral n\u00e3o causa.<\/p>\n<p>Vale notar que a energia do f\u00f3ton depende apenas da cor (comprimento de onda) da luz, nunca do seu brilho. A intensidade determina <em>quantos<\/em> f\u00f3tons chegam por segundo; cada f\u00f3ton individual sempre carrega exatamente \\(h\\nu\\). Se voc\u00ea vai combinar energias luminosas com energias de liga\u00e7\u00e3o para estimar entalpias de rea\u00e7\u00e3o, nossa <a href=\"https:\/\/wpcalc.com\/pt\/quimica\/calculadora-entalpia-reacao-energia-de-ligacao\/\">calculadora de Entalpia de rea\u00e7\u00e3o a partir de energias de liga\u00e7\u00e3o<\/a> \u00e9 uma ferramenta complementar natural.<\/p>\n<h2>Valores de refer\u00eancia<\/h2>\n<table>\n<thead>\n<tr>\n<th>Comprimento de onda<\/th>\n<th>Regi\u00e3o<\/th>\n<th>Energia (eV)<\/th>\n<th>Energia (kJ\/mol)<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>200 nm<\/td>\n<td>UV distante<\/td>\n<td>6,20<\/td>\n<td>598<\/td>\n<\/tr>\n<tr>\n<td>254 nm<\/td>\n<td>UV (l\u00e2mpada de Hg)<\/td>\n<td>4,89<\/td>\n<td>471<\/td>\n<\/tr>\n<tr>\n<td>350 nm<\/td>\n<td>UV pr\u00f3ximo<\/td>\n<td>3,54<\/td>\n<td>342<\/td>\n<\/tr>\n<tr>\n<td>450 nm<\/td>\n<td>Vis\u00edvel (azul)<\/td>\n<td>2,76<\/td>\n<td>266<\/td>\n<\/tr>\n<tr>\n<td>500 nm<\/td>\n<td>Vis\u00edvel (verde)<\/td>\n<td>2,48<\/td>\n<td>239<\/td>\n<\/tr>\n<tr>\n<td>700 nm<\/td>\n<td>Vis\u00edvel (borda vermelha)<\/td>\n<td>1,77<\/td>\n<td>171<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Premissas e limita\u00e7\u00f5es<\/h2>\n<ul>\n<li>O c\u00e1lculo pressup\u00f5e que a luz se propaga no <strong>v\u00e1cuo<\/strong>. Para o ar, a diferen\u00e7a \u00e9 desprez\u00edvel \u2014 a velocidade da luz no ar \u00e9 apenas cerca de 0,03% menor que no v\u00e1cuo, o que altera a correspond\u00eancia entre comprimento de onda e frequ\u00eancia de forma impercept\u00edvel na maioria das aplica\u00e7\u00f5es.<\/li>\n<li>As constantes \\(h\\), \\(c\\) e \\(N_A\\) s\u00e3o os valores exatos do SI de 2019, de modo que a \u00fanica fonte de imprecis\u00e3o \u00e9 o pr\u00f3prio valor inserido.<\/li>\n<li>O comprimento de onda e a frequ\u00eancia devem se referir ao mesmo meio; misturar um comprimento de onda no v\u00e1cuo com uma frequ\u00eancia medida no meio introduziria um erro igual ao \u00edndice de refra\u00e7\u00e3o.<\/li>\n<li>A calculadora trata a luz como f\u00f3tons individuais. Efeitos como a absor\u00e7\u00e3o multif\u00f3ton (em que dois f\u00f3tons de menor energia s\u00e3o absorvidos juntos) s\u00e3o processos n\u00e3o lineares que n\u00e3o s\u00e3o cobertos pela rela\u00e7\u00e3o de Planck simples.<\/li>\n<li>Ao comparar com energias de liga\u00e7\u00e3o, lembre-se de que um f\u00f3ton precisa fornecer <em>pelo menos<\/em> a energia de dissocia\u00e7\u00e3o da liga\u00e7\u00e3o em um \u00fanico evento de absor\u00e7\u00e3o; o excedente aparece como energia cin\u00e9tica, calor ou fluoresc\u00eancia.<\/li>\n<\/ul>\n<p>Se o seu trabalho envolve a natureza ondulat\u00f3ria da luz \u2014 por exemplo, difra\u00e7\u00e3o por cristais \u2014, voc\u00ea tamb\u00e9m pode achar \u00fatil a nossa <a href=\"https:\/\/wpcalc.com\/pt\/quimica\/calculadora-lei-de-bragg\/\">calculadora da Lei de Bragg<\/a>, que relaciona o comprimento de onda com os \u00e2ngulos de difra\u00e7\u00e3o, ou a <a href=\"https:\/\/wpcalc.com\/en\/chemistry\/standard-cell-potential-calculator\/\">calculadora de Potencial padr\u00e3o de c\u00e9lula<\/a> para converter entre voltagens eletroqu\u00edmicas e energias de el\u00e9trons em eV.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Calcule a energia de um f\u00f3ton a partir do comprimento de onda ou da frequ\u00eancia. Basta informar um dos dois valores para obter a energia por f\u00f3ton em joules e el\u00e9trons-volt, al\u00e9m da energia por mol de f\u00f3tons em kJ\/mol.<\/p>\n","protected":false},"author":3168,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[3],"tags":[69],"class_list":["post-2169","post","type-post","status-publish","format-standard","hentry","category-quimica","tag-espectrofotometria"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/pt\/wp-json\/wp\/v2\/posts\/2169","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wpcalc.com\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wpcalc.com\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wpcalc.com\/pt\/wp-json\/wp\/v2\/users\/3168"}],"replies":[{"embeddable":true,"href":"https:\/\/wpcalc.com\/pt\/wp-json\/wp\/v2\/comments?post=2169"}],"version-history":[{"count":1,"href":"https:\/\/wpcalc.com\/pt\/wp-json\/wp\/v2\/posts\/2169\/revisions"}],"predecessor-version":[{"id":2776,"href":"https:\/\/wpcalc.com\/pt\/wp-json\/wp\/v2\/posts\/2169\/revisions\/2776"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/pt\/wp-json\/wp\/v2\/media?parent=2169"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/pt\/wp-json\/wp\/v2\/categories?post=2169"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/pt\/wp-json\/wp\/v2\/tags?post=2169"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}