Questões de Vestibular UNICAMP 2015 para Vestibular
Foram encontradas 90 questões
Com a crescente crise mundial de dengue, as pesquisas pela busca tanto de vacinas quanto de repelentes de insetos têm se intensificado. Nesse contexto, os compostos I e II abaixo representados têm propriedades muito distintas: enquanto um deles tem caráter ácido e atrai os insetos, o outro tem caráter básico e não os atrai.
Baseado nessas informações, pode-se afirmar
corretamente que o composto
Em seu livro Como se faz Química, o Professor Aécio Chagas afirma que “quem transforma a matéria, sem pensar sobre ela, não é, e jamais será um químico”. Considere alguns produtos que um cozinheiro reconhece nas linhas 1-4 do quadro a seguir, e aqueles que um químico reconhece nas linhas 5-8.
Um químico, familiarizado com as atividades culinárias,
relacionaria as linhas
Atualmente, parece que a Química vem seduzindo as pessoas e tem-se observado um número cada vez maior de pessoas portando tatuagens que remetem ao conhecimento químico. As figuras a seguir mostram duas tatuagens muito parecidas, com as correspondentes imagens tatuadas mais bem definidas abaixo.
As imagens representam duas fórmulas estruturais, que
correspondem a dois
A preocupação com a emissão de gases poluentes no meio ambiente está muito presente na indústria automobilística. Recentemente, uma das soluções encontradas para contornar esse problema nos veículos movidos a Diesel foi o desenvolvimento do Arla 32, uma solução de ureia em água, que atua nos sistemas de exaustão, de acordo com as equações químicas abaixo:
CO(NH2)2 + H2O → 2NH3 + CO2
4NH3 + 4NO + O2 → 4N2 + 6H2O
4NH3 + 2NO2 + O2 → 3N2 + 6H2O.
Com base nessas informações, pode-se afirmar
corretamente que a ação do Arla 32 leva a uma redução
A comparação entre as proporções isotópicas de amostras de um mesmo material, que têm a mesma idade, encontradas em diferentes regiões, pode ser utilizada para revelar se elas têm ou não a mesma origem. Se as proporções são iguais, então é possível que tenham a mesma origem, mas se forem diferentes, é certeza que não têm a mesma origem. A tabela a seguir apresenta os dados de algumas amostras de água, incluindo a de um cometa no qual uma sonda pousou recentemente.
*nd – não disponível
Com base nesses dados, pode-se afirmar corretamente que
a água de nosso planeta
Os compostos (NH4)H2PO4 e NaHCO3 são usados em extintores como agentes de combate ao fogo. Quando lançados sobre uma chama, ocorrem as seguintes transformações:
(NH4)H2PO4 → NH3 + H3PO4
H3PO4 → polifosfato (viscoso)
NaHCO3 → CO2 + H2O + Na2CO3 (particulado).
No combate a todos os tipos de incêndio, a nuvem formada
de gás é importante, mas naqueles envolvendo materiais
sólidos, o depósito do material oriundo da transformação
do agente de combate sobre o combustível tem papel
decisivo. Assim, o agente (NH4)H2PO4 pode substituir o
NaHCO3 em qualquer situação, mas o contrário não é
verdade. Isso permite concluir que no combate ao incêndio
que envolve
A tira tematiza a contribuição da atividade humana para a deterioração do meio ambiente. Do diálogo apresentado, pode-se depreender que os ursos já sabiam
"If you believe in freedom of speech, you believe in freedom of speech for views you don’t like. Goebbels was in favor of freedom of speech for views he liked. So was Stalin. If you’re in favor of freedom of speech, that means you’re in favor of freedom of speech precisely for views you despise."
(NoamChomsky)
(Fonte: http://noam-chomsky.tumblr.com/post/7223808896/if-youbelieve-in-freedom-of-speech-you-believe.)
O autor do texto
Na tirinha, Calvin dá dicas sobre como
O texto anuncia um
Advice for new students from those who know (old students)
The first day of college I was a ball of nerves. I remember walking into my first class and running to the first seat I found, thinking everyone would be staring at me. But nobody seemed to notice and then it hit me: The fact that nobody knew me meant nobody would judge, which, upon reflection, was what I was scared of the most. I told myself to let go. All along the year, I forced myself into situations that were uncomfortable for me – for example, auditioning for a dance piece. Believe it or not, that performance was a highlight of my freshman year. My advice: challenge yourself to try something new, something you couldn’t have done in high school. – Ria Jagasia, Vanderbilt University, ’18.
(Adaptado de http://www.nytimes.com/2015/08/02/ education/edlife/ advice-for-new-students-from-those-who-know-old-students.html?ref= edlife.)
Advice for new students from those who know (old students)
The first day of college I was a ball of nerves. I remember walking into my first class and running to the first seat I found, thinking everyone would be staring at me. But nobody seemed to notice and then it hit me: The fact that nobody knew me meant nobody would judge, which, upon reflection, was what I was scared of the most. I told myself to let go. All along the year, I forced myself into situations that were uncomfortable for me – for example, auditioning for a dance piece. Believe it or not, that performance was a highlight of my freshman year. My advice: challenge yourself to try something new, something you couldn’t have done in high school. – Ria Jagasia, Vanderbilt University, ’18.
(Adaptado de http://www.nytimes.com/2015/08/02/ education/edlife/ advice-for-new-students-from-those-who-know-old-students.html?ref= edlife.)
If apes go extinct, so could entire forests
Bonobos eat a lot of fruit, and fruit contains seeds. Those seeds travel through a bonobo’s digestive system while bonobo itself travels around the forest. A few hours later, the seeds end up being deposited far from where the fruits were plucked. And that is where the new trees come from.
According to a paper recently published, if the bonobos disappeared, the plants would also likely go extinct, for many trees and plants species in Congo rely almost exclusively on bonobos for seed dispersal.
The bonobo has two major functions here. First of all, many seeds will not germinate well unless they have been “handled” by another species. Stomach acids and intestinal processes make the seed more able to absorb water and later sprout.
Secondly, many seeds will not succeed if they remain too close to their parental trees. The seeds that fell to the ground near their parents did not survive because they were choked off by the nearby plants. The bonobos eat about 3,5 hours every day and travel a mean of 1.2 kilometers from meal sites before defecating.
(Adaptado de http://blogs.scientificamerican.com/extinction-countdown /if-apes-go-extinct-so-could-entire-forests/.)
Qual é a explicação para o título?
We’ve modified our behavior so we can text and walk
Texting – or checking social media or reading/responding to mail or reading the news or checking the weather or watching a video – while walking is a pretty common phenomenon. It’s so common that most people who own a mobile device have become texting walkers.
Research suggests that these texters adopt protective measures to minimize the risk of accidents when walking. They’re less likely to trip because they shorten their step length, reduce step frequency, lengthen the time during which both feet are in contact with the ground, and increase obstacle clearance height. Taken together this creates an exaggerated image of walking, but it apparently slows the walker enough so that he registers some of what is happening around him and can compensate for it.
(Adaptado de http://blogs.scientificamerican.com/anthropology-in-practice/we-ve-modified-our-behavior-so-we-can-text-and-walk/.)
We’ve modified our behavior so we can text and walk
Texting – or checking social media or reading/responding to mail or reading the news or checking the weather or watching a video – while walking is a pretty common phenomenon. It’s so common that most people who own a mobile device have become texting walkers.
Research suggests that these texters adopt protective measures to minimize the risk of accidents when walking. They’re less likely to trip because they shorten their step length, reduce step frequency, lengthen the time during which both feet are in contact with the ground, and increase obstacle clearance height. Taken together this creates an exaggerated image of walking, but it apparently slows the walker enough so that he registers some of what is happening around him and can compensate for it.
(Adaptado de http://blogs.scientificamerican.com/anthropology-in-practice/we-ve-modified-our-behavior-so-we-can-text-and-walk/.)