Questões do ENEM: Universidade Estadual do Centro-Oeste (UNICENTRO)

Use os filtros para chegar às questões que interessam. Cada resultado abre em uma página própria com enunciado, alternativas e gabarito.

Resultados

1.729 questões encontradas. Mostrando a página 34 de 87.

  • BE2E5CF9-FF

    Química

    Fórmulas, Balanceamento e Leis ponderais das reações químicas
    UNICENTRO · 2017MédioEntre para guardar nos favoritos

    Considere a reação abaixo (não balanceada):


    NH3 + O2  ➔   NO + H2O

    O número de moléculas de NO formadas na reação da amônia (NH3) com 2,0 .1021 moléculas de oxigênio será:

    Escolha uma alternativa para a questão be2e5cf9-ff
  • BE2965BA-FF

    Química

    Eletroquímica: Oxirredução, Potenciais Padrão de Redução, Pilha, Eletrólise e Leis de Faraday.
    UNICENTRO · 2017FácilEntre para guardar nos favoritos

    Dadas as equações químicas balanceadas:


    Fe(s) ➜  Fe2+(aq) + 2e- (oxidação)

    O2(g) + 2H2O(l) + 4e-   ➜   4OH- (redução)


    A equação química balanceada que descreve a oxidação do ferro em meio aquoso neutro será:

    Escolha uma alternativa para a questão be2965ba-ff
  • BE214A22-FF

    Química

    Fórmulas, Balanceamento e Leis ponderais das reações químicas
    UNICENTRO · 2017MédioEntre para guardar nos favoritos

    Considere a equação química (não balanceada) para a combustão do etanol:


    C2H6O(l) + O2(g)  ➜  CO2(g) + H2O(l)


    Dados: Entalpia de formação de C2H6O(l) = – 66 kcal/mol

                Entalpia de formação de CO2(g) = – 94 kcal/mol

                Entalpia de formação de H2O(l) = – 68 kcal/mol


    A entalpia de combustão em kcal/mol será:

    Escolha uma alternativa para a questão be214a22-ff
  • BE1E50AF-FF

    Química

    Soluções e Substâncias Inorgânicas
    UNICENTRO · 2017FácilEntre para guardar nos favoritos
    Considere uma solução aquosa saturada de KNO3 a 20°C, com precipitado de fundo, e os seguintes valores:

                                                                               20°C   30°C    40°C    50°C
    Solubilidade do KNO3 por 100 g de água         31,6g   45,8g   63,9     85,5


    De acordo com os dados acima, para diminuir o precipitado de fundo devemos:
    Escolha uma alternativa para a questão be1e50af-ff
  • BE1B7407-FF

    Matemática

    Sistemas Lineares
    UNICENTRO · 2017MédioEntre para guardar nos favoritos
    Sobre sistemas lineares, assinale a única alternativa correta.
    Escolha uma alternativa para a questão be1b7407-ff
  • BE15944D-FF

    Matemática

    Probabilidade
    UNICENTRO · 2017FácilEntre para guardar nos favoritos
    Monique brincava com um dado quando resolveu analisar a probabilidade de tirar um número primo ao jogar o objeto para cima. Verificando o dado após sua jogada, foi obtida face com número maior que 2. Logo, a probabilidade deste número ser primo está na alternativa:
    Escolha uma alternativa para a questão be15944d-ff
  • BE12DE50-FF

    Matemática

    Probabilidade
    UNICENTRO · 2017MédioEntre para guardar nos favoritos
    Estudando probabilidade, Vicente se deparou com uma relação de quatro exercícios já resolvidos. Após conferência dos cálculos, descobriu um erro no exercício citado na alternativa:
    Escolha uma alternativa para a questão be12de50-ff
  • BE1036DE-FF

    Matemática

    Geometria Espacial
    UNICENTRO · 2017MédioEntre para guardar nos favoritos
    Das afirmações abaixo, assinale a única que está INCORRETA.
    Escolha uma alternativa para a questão be1036de-ff
  • BE0D704E-FF

    Matemática

    Geometria Espacial
    UNICENTRO · 2017MédioEntre para guardar nos favoritos
    Analise as sentenças abaixo e assinale a única correta.

    I- Os poliedros são formas espaciais sólidas delimitadas por superfícies planas poligonais. Uma superfície poligonal corresponde a um polígono reunido com a parte do plano em seu interior.
    II- Os poliedros possuem algumas características e uma delas é que eles são limitados por superfícies planas poligonais chamadas de faces do poliedro.
    III- As superfícies poligonais que delimitam o poliedro interceptam-se em lados dos polígonos. Esses segmentos são chamados de arestas do Poliedro.
    IV-O cubo é um poliedro cujas arestas constam com diferentes tamanhos em um único cubo.
    Escolha uma alternativa para a questão be0d704e-ff
  • BE0A8EAC-FF

    Inglês

    Interpretação de texto | Reading comprehension
    UNICENTRO · 2017MédioEntre para guardar nos favoritos
    Can talking on a mobile phone be hazardous to your health? It is difficult to know for sure. Some research suggests that heavy users of mobile phones are at a greater risk of developing cancerous brain tumours. However, many other studies suggest there are no links between cancer and mobile phone use.

    The main problem with the current research is that mobile phones have only been popular since the 1990s. As a result, it is impossible to study long-term exposure to mobile phones. This concerns many health professionals who point out that certain cancers can take over twenty years to develop. Another concern about these studies is that many have been funded by the mobile phone industry or those who benefit from it.

    Over five billion people now use mobile phones on a daily basis, and many talk for more than an hour a day. Mobile phone antennas are similar to microwave ovens. While both rely on electromagnetic radiation (EMR), the radio waves in mobile phones are lower in frequency. Microwave ovens have radio wave frequencies that are high enough to cook food, and they are also known to be dangerous to human tissues like those in the brain. The concern is that the lowerfrequency radio waves that mobile phones rely on may also be dangerous. It seems logical that holding a heat source near your brain for a long period of time is a potential health hazard.

    Some researchers believe that other types of wireless technology may also be dangerous to human health, including cordless phones, wireless gaming consoles, and laptop or tablet computers with wireless connections. They suggest replacing all cordless and wireless devices with wired ones where possible. They also say that many cordless phones can emit dangerous levels of Electromagnetic Radiation even when they are not in use. They even suggest keeping electronic devices such as desktop and tablet computers out of the bedroom, or at least six feet from the head while we're sleeping.

    A growing number of health professionals worldwide are recommending that mobile phone users err on the side of caution until more definitive studies can be conducted. They use the example of tobacco to illustrate the potential risks. Many years ago, people smoked freely and were not concerned about the effects of cigarettes on their health. Today, people know that cigarettes cause lung cancer, though it is still unknown exactly how or why. Some doctors fear that the same thing will happen with mobile phones. In May 2016, the UK's Independent newspaper reported on research by the US government's National Toxicology Program that showed a slight increase in brain tumours among rats exposed to the type of radio frequencies commonly emitted by mobile phones. This doesn't prove that mobile phones can cause brain tumours in humans, but it does show that it's possible. As a result, many experts now recommend texting or using head sets or speaker phones instead of holding a mobile phone to the ear.

    (Source: https://www.englishclub.com/reading/health/cell-phone.htm)

    From the sentence “mobile phones have only been popular since the 1990s", it is possible to understand that:
    Escolha uma alternativa para a questão be0a8eac-ff
  • BE07A7CE-FF

    Inglês

    Interpretação de texto | Reading comprehension
    UNICENTRO · 2017MédioEntre para guardar nos favoritos
    Can talking on a mobile phone be hazardous to your health? It is difficult to know for sure. Some research suggests that heavy users of mobile phones are at a greater risk of developing cancerous brain tumours. However, many other studies suggest there are no links between cancer and mobile phone use.

    The main problem with the current research is that mobile phones have only been popular since the 1990s. As a result, it is impossible to study long-term exposure to mobile phones. This concerns many health professionals who point out that certain cancers can take over twenty years to develop. Another concern about these studies is that many have been funded by the mobile phone industry or those who benefit from it.

    Over five billion people now use mobile phones on a daily basis, and many talk for more than an hour a day. Mobile phone antennas are similar to microwave ovens. While both rely on electromagnetic radiation (EMR), the radio waves in mobile phones are lower in frequency. Microwave ovens have radio wave frequencies that are high enough to cook food, and they are also known to be dangerous to human tissues like those in the brain. The concern is that the lowerfrequency radio waves that mobile phones rely on may also be dangerous. It seems logical that holding a heat source near your brain for a long period of time is a potential health hazard.

    Some researchers believe that other types of wireless technology may also be dangerous to human health, including cordless phones, wireless gaming consoles, and laptop or tablet computers with wireless connections. They suggest replacing all cordless and wireless devices with wired ones where possible. They also say that many cordless phones can emit dangerous levels of Electromagnetic Radiation even when they are not in use. They even suggest keeping electronic devices such as desktop and tablet computers out of the bedroom, or at least six feet from the head while we're sleeping.

    A growing number of health professionals worldwide are recommending that mobile phone users err on the side of caution until more definitive studies can be conducted. They use the example of tobacco to illustrate the potential risks. Many years ago, people smoked freely and were not concerned about the effects of cigarettes on their health. Today, people know that cigarettes cause lung cancer, though it is still unknown exactly how or why. Some doctors fear that the same thing will happen with mobile phones. In May 2016, the UK's Independent newspaper reported on research by the US government's National Toxicology Program that showed a slight increase in brain tumours among rats exposed to the type of radio frequencies commonly emitted by mobile phones. This doesn't prove that mobile phones can cause brain tumours in humans, but it does show that it's possible. As a result, many experts now recommend texting or using head sets or speaker phones instead of holding a mobile phone to the ear.

    (Source: https://www.englishclub.com/reading/health/cell-phone.htm)

    Considering the text, fill the parenthesis with T (true) or F (false):

    ( ) One of the problems of current research on the hazards of mobile phones is that they have been popular for too long, which creates a lot of data do be analyzed.
    ( ) Regarding the risks mobile phones can pose to our health, health professionals worldwide believe it is better to be cautious until more conclusive research is conducted.
    ( ) The frequency used by mobile phones is significantly higher than the frequency of microwaves, hence the health problems.
    ( ) Health professionals use the example of the tobacco industry to illustrate that mobile phones can be dangerous, even though research is still not conclusive on that.

    The correct sequence, from top to bottom is:
    Escolha uma alternativa para a questão be07a7ce-ff
  • BE04BDD3-FF

    Inglês

    Interpretação de texto | Reading comprehension
    UNICENTRO · 2017MédioEntre para guardar nos favoritos
    Can talking on a mobile phone be hazardous to your health? It is difficult to know for sure. Some research suggests that heavy users of mobile phones are at a greater risk of developing cancerous brain tumours. However, many other studies suggest there are no links between cancer and mobile phone use.

    The main problem with the current research is that mobile phones have only been popular since the 1990s. As a result, it is impossible to study long-term exposure to mobile phones. This concerns many health professionals who point out that certain cancers can take over twenty years to develop. Another concern about these studies is that many have been funded by the mobile phone industry or those who benefit from it.

    Over five billion people now use mobile phones on a daily basis, and many talk for more than an hour a day. Mobile phone antennas are similar to microwave ovens. While both rely on electromagnetic radiation (EMR), the radio waves in mobile phones are lower in frequency. Microwave ovens have radio wave frequencies that are high enough to cook food, and they are also known to be dangerous to human tissues like those in the brain. The concern is that the lowerfrequency radio waves that mobile phones rely on may also be dangerous. It seems logical that holding a heat source near your brain for a long period of time is a potential health hazard.

    Some researchers believe that other types of wireless technology may also be dangerous to human health, including cordless phones, wireless gaming consoles, and laptop or tablet computers with wireless connections. They suggest replacing all cordless and wireless devices with wired ones where possible. They also say that many cordless phones can emit dangerous levels of Electromagnetic Radiation even when they are not in use. They even suggest keeping electronic devices such as desktop and tablet computers out of the bedroom, or at least six feet from the head while we're sleeping.

    A growing number of health professionals worldwide are recommending that mobile phone users err on the side of caution until more definitive studies can be conducted. They use the example of tobacco to illustrate the potential risks. Many years ago, people smoked freely and were not concerned about the effects of cigarettes on their health. Today, people know that cigarettes cause lung cancer, though it is still unknown exactly how or why. Some doctors fear that the same thing will happen with mobile phones. In May 2016, the UK's Independent newspaper reported on research by the US government's National Toxicology Program that showed a slight increase in brain tumours among rats exposed to the type of radio frequencies commonly emitted by mobile phones. This doesn't prove that mobile phones can cause brain tumours in humans, but it does show that it's possible. As a result, many experts now recommend texting or using head sets or speaker phones instead of holding a mobile phone to the ear.

    (Source: https://www.englishclub.com/reading/health/cell-phone.htm)

    In the fourth paragraph, the modal verb may expresses:
    Escolha uma alternativa para a questão be04bdd3-ff
  • BE00F8CC-FF

    Inglês

    Interpretação de texto | Reading comprehension
    UNICENTRO · 2017FácilEntre para guardar nos favoritos
    Can talking on a mobile phone be hazardous to your health? It is difficult to know for sure. Some research suggests that heavy users of mobile phones are at a greater risk of developing cancerous brain tumours. However, many other studies suggest there are no links between cancer and mobile phone use.

    The main problem with the current research is that mobile phones have only been popular since the 1990s. As a result, it is impossible to study long-term exposure to mobile phones. This concerns many health professionals who point out that certain cancers can take over twenty years to develop. Another concern about these studies is that many have been funded by the mobile phone industry or those who benefit from it.

    Over five billion people now use mobile phones on a daily basis, and many talk for more than an hour a day. Mobile phone antennas are similar to microwave ovens. While both rely on electromagnetic radiation (EMR), the radio waves in mobile phones are lower in frequency. Microwave ovens have radio wave frequencies that are high enough to cook food, and they are also known to be dangerous to human tissues like those in the brain. The concern is that the lowerfrequency radio waves that mobile phones rely on may also be dangerous. It seems logical that holding a heat source near your brain for a long period of time is a potential health hazard.

    Some researchers believe that other types of wireless technology may also be dangerous to human health, including cordless phones, wireless gaming consoles, and laptop or tablet computers with wireless connections. They suggest replacing all cordless and wireless devices with wired ones where possible. They also say that many cordless phones can emit dangerous levels of Electromagnetic Radiation even when they are not in use. They even suggest keeping electronic devices such as desktop and tablet computers out of the bedroom, or at least six feet from the head while we're sleeping.

    A growing number of health professionals worldwide are recommending that mobile phone users err on the side of caution until more definitive studies can be conducted. They use the example of tobacco to illustrate the potential risks. Many years ago, people smoked freely and were not concerned about the effects of cigarettes on their health. Today, people know that cigarettes cause lung cancer, though it is still unknown exactly how or why. Some doctors fear that the same thing will happen with mobile phones. In May 2016, the UK's Independent newspaper reported on research by the US government's National Toxicology Program that showed a slight increase in brain tumours among rats exposed to the type of radio frequencies commonly emitted by mobile phones. This doesn't prove that mobile phones can cause brain tumours in humans, but it does show that it's possible. As a result, many experts now recommend texting or using head sets or speaker phones instead of holding a mobile phone to the ear.

    (Source: https://www.englishclub.com/reading/health/cell-phone.htm)

    In the first paragraph, the word however tells the reader that the following sentence will:
    Escolha uma alternativa para a questão be00f8cc-ff
  • BDFE2C1F-FF

    Inglês

    Interpretação de texto | Reading comprehension
    UNICENTRO · 2017MédioEntre para guardar nos favoritos
    Can talking on a mobile phone be hazardous to your health? It is difficult to know for sure. Some research suggests that heavy users of mobile phones are at a greater risk of developing cancerous brain tumours. However, many other studies suggest there are no links between cancer and mobile phone use.

    The main problem with the current research is that mobile phones have only been popular since the 1990s. As a result, it is impossible to study long-term exposure to mobile phones. This concerns many health professionals who point out that certain cancers can take over twenty years to develop. Another concern about these studies is that many have been funded by the mobile phone industry or those who benefit from it.

    Over five billion people now use mobile phones on a daily basis, and many talk for more than an hour a day. Mobile phone antennas are similar to microwave ovens. While both rely on electromagnetic radiation (EMR), the radio waves in mobile phones are lower in frequency. Microwave ovens have radio wave frequencies that are high enough to cook food, and they are also known to be dangerous to human tissues like those in the brain. The concern is that the lowerfrequency radio waves that mobile phones rely on may also be dangerous. It seems logical that holding a heat source near your brain for a long period of time is a potential health hazard.

    Some researchers believe that other types of wireless technology may also be dangerous to human health, including cordless phones, wireless gaming consoles, and laptop or tablet computers with wireless connections. They suggest replacing all cordless and wireless devices with wired ones where possible. They also say that many cordless phones can emit dangerous levels of Electromagnetic Radiation even when they are not in use. They even suggest keeping electronic devices such as desktop and tablet computers out of the bedroom, or at least six feet from the head while we're sleeping.

    A growing number of health professionals worldwide are recommending that mobile phone users err on the side of caution until more definitive studies can be conducted. They use the example of tobacco to illustrate the potential risks. Many years ago, people smoked freely and were not concerned about the effects of cigarettes on their health. Today, people know that cigarettes cause lung cancer, though it is still unknown exactly how or why. Some doctors fear that the same thing will happen with mobile phones. In May 2016, the UK's Independent newspaper reported on research by the US government's National Toxicology Program that showed a slight increase in brain tumours among rats exposed to the type of radio frequencies commonly emitted by mobile phones. This doesn't prove that mobile phones can cause brain tumours in humans, but it does show that it's possible. As a result, many experts now recommend texting or using head sets or speaker phones instead of holding a mobile phone to the ear.

    (Source: https://www.englishclub.com/reading/health/cell-phone.htm)

    The main objective of the article is to:
    Escolha uma alternativa para a questão bdfe2c1f-ff
  • BDF88629-FF

    Literatura

    Escolas Literárias
    UNICENTRO · 2017MédioEntre para guardar nos favoritos
    Assinale a alternativa características do simbolismo.
    Escolha uma alternativa para a questão bdf88629-ff
  • BDF5BA9C-FF

    Português

    Regência
    UNICENTRO · 2017MédioEntre para guardar nos favoritos
    Leia o texto a seguir para responder a questão

          Um humano sai em busca de um mamute, persegue-o durante o dia, arma a emboscada e, depois de inúmeras tentativas, consegue matá-lo e abocanhar seu quinhão de carne.
          Em seguida, exausto, volta para casa com o firme propósito de deitar e rolar no tapete com o filho, contar historinhas repetitivas e ignorar a bronca merecida do pimpolho, pois, afinal, trata-se de um pai/mãe ausente o dia todo.
          Antes de dormir, ainda se verá no espelho com um olhar de feroz reprovação pela falta de tempo e de pique para a ginástica, para o sexo e para a vida social.
      Bem-vindo à geração cem por cento, que acredita que pode e deve dar conta de tudo e de fazer escolhas que não impliquem perdas.
          Uma aluna comentou esse fenômeno sabiamente: "Escolha sua perda!". Sim, é disso que se trata. Uma ínfima parcela da população pode se dar ao luxo de não ter que caçar seu mamute diariamente. Além disso, temos outras aspirações, que nos fazem mais do que caçadores, que nos fazem humanos.
      Ainda assim, somos assombrados pela ideia de que nossos filhos serão traumatizados pela nossa ausência. Aqui funciona a lógica de que pai e mãe são oxigênio, de que qualquer outro adulto cuidando deles será fatal. [...]
          Nossos filhos viverão em média 4 a 5 décadas mais do que nós -ou seja, os deixaremos órfãos, na melhor das hipóteses. Ausência fundamental que marca o sentido da parentalidade, pois acarreta criar sujeitos rumo à autonomia.
    [...]
       Há, ainda, outras ausências, menos radicais do que a morte, com as quais devemos aprender a lidar. Ausentamonos trabalhando, amando outras pessoas, amando outras coisas e amando a nós mesmos. [...] Ninguém merece ser tudo para um pai ou uma mãe. Por outro lado, nenhum adulto merece criar uma criança sem ajuda, sem respiro, tendo que gostar de brincar por obrigação. [...]
          A tarefa parental é imensa e vitalícia. Será exercida por quem assumir essa responsabilidade radical, não cabendo aqui fazer diferença entre homens e mulheres, pais e mães. Quem tomar para si essa missão só poderá cumpri-la a partir de suas escolhas e consequentes perdas, sem fazer da parentalidade um poço de ressentimento e culpas, cuja conta quem paga são os filhos.
          Então, façamos a lição de casa. O que realmente é possível para cada família específica, para além de um mundo fantasioso no qual os pais se dedicariam integralmente aos filhos como se isso fosse bom para as crianças? Perguntemo-nos também o que é desejável para nós, pois a presença ressentida não passa desapercebida aos pequenos.
          Ao deixá-los com outros, sejam familiares ou profissionais, cabe assumir essa escolha, não valendo controlar à distância avós, babás e professores, o que é enlouquecedor. Enfim, escolha sua perda e aprenda a se ausentar.
    (Folha de São Paulo, VERA IACONELLI, 10 set. 2017, com adaptações)
    Assinale a alternativa na qual a regência do verbo “implicar” é a mesma da empregada no trecho: “que acredita que pode e deve dar conta de tudo e de fazer escolhas que não impliquem perdas”
    Escolha uma alternativa para a questão bdf5ba9c-ff
  • BDF308A9-FF

    Português

    Coesão e coerência
    UNICENTRO · 2017FácilEntre para guardar nos favoritos
    Leia o texto a seguir para responder a questão

          Um humano sai em busca de um mamute, persegue-o durante o dia, arma a emboscada e, depois de inúmeras tentativas, consegue matá-lo e abocanhar seu quinhão de carne.
          Em seguida, exausto, volta para casa com o firme propósito de deitar e rolar no tapete com o filho, contar historinhas repetitivas e ignorar a bronca merecida do pimpolho, pois, afinal, trata-se de um pai/mãe ausente o dia todo.
          Antes de dormir, ainda se verá no espelho com um olhar de feroz reprovação pela falta de tempo e de pique para a ginástica, para o sexo e para a vida social.
      Bem-vindo à geração cem por cento, que acredita que pode e deve dar conta de tudo e de fazer escolhas que não impliquem perdas.
          Uma aluna comentou esse fenômeno sabiamente: "Escolha sua perda!". Sim, é disso que se trata. Uma ínfima parcela da população pode se dar ao luxo de não ter que caçar seu mamute diariamente. Além disso, temos outras aspirações, que nos fazem mais do que caçadores, que nos fazem humanos.
      Ainda assim, somos assombrados pela ideia de que nossos filhos serão traumatizados pela nossa ausência. Aqui funciona a lógica de que pai e mãe são oxigênio, de que qualquer outro adulto cuidando deles será fatal. [...]
          Nossos filhos viverão em média 4 a 5 décadas mais do que nós -ou seja, os deixaremos órfãos, na melhor das hipóteses. Ausência fundamental que marca o sentido da parentalidade, pois acarreta criar sujeitos rumo à autonomia.
    [...]
       Há, ainda, outras ausências, menos radicais do que a morte, com as quais devemos aprender a lidar. Ausentamonos trabalhando, amando outras pessoas, amando outras coisas e amando a nós mesmos. [...] Ninguém merece ser tudo para um pai ou uma mãe. Por outro lado, nenhum adulto merece criar uma criança sem ajuda, sem respiro, tendo que gostar de brincar por obrigação. [...]
          A tarefa parental é imensa e vitalícia. Será exercida por quem assumir essa responsabilidade radical, não cabendo aqui fazer diferença entre homens e mulheres, pais e mães. Quem tomar para si essa missão só poderá cumpri-la a partir de suas escolhas e consequentes perdas, sem fazer da parentalidade um poço de ressentimento e culpas, cuja conta quem paga são os filhos.
          Então, façamos a lição de casa. O que realmente é possível para cada família específica, para além de um mundo fantasioso no qual os pais se dedicariam integralmente aos filhos como se isso fosse bom para as crianças? Perguntemo-nos também o que é desejável para nós, pois a presença ressentida não passa desapercebida aos pequenos.
          Ao deixá-los com outros, sejam familiares ou profissionais, cabe assumir essa escolha, não valendo controlar à distância avós, babás e professores, o que é enlouquecedor. Enfim, escolha sua perda e aprenda a se ausentar.
    (Folha de São Paulo, VERA IACONELLI, 10 set. 2017, com adaptações)
    A partir do trecho: “Quem tomar para si essa missão só poderá cumpri-la a partir de suas escolhas e consequentes perdas, sem fazer da parentalidade um poço de ressentimento e culpas, cuja conta quem paga são os filhos”, é correto considerar que o pronome em destaque refere-se a:
    Escolha uma alternativa para a questão bdf308a9-ff