[IME - 2011/2012 - 1 FASE] Sobre a diferena entre slido amorfo e slido cristalino, pode-se afirmar o seguinte:
[IME - 2011/2012 - 1 FASE] Um grupo de alunos desenvolveu um estudo sobre trs reaes irreversveis de ordens zero, um e dois. Contudo, ao se reunirem para confeccionar o relatrio, no identificaram a correspondncia entre as colunas da tabela abaixo e as respectivas ordens de reao. t (s) C1 (mol/L) C2 (mol/L) C3 (mol/L) 200 0,8000 0,8333 0,8186 210 0,7900 0,8264 0,8105 220 0,7800 0,8196 0,8024 230 0,7700 0,8130 0,7945 240 0,7600 0,8064 0,7866 Considere que o modelo descreva adequadamente as velocidades das reaes estudadas. Considere ainda que as magnitudes das constantes de velocidade especfica de todas as reaes so idnticas da reao de segunda ordem, que 1,0 x 10-3 L/mol s. Assim, pode-se afirmar que C1, C2 e C3 referem-se, respectivamente, a reaes de ordem
[IME - 2011/2012 - 1 FASE] As variveis de um experimento de difrao de raios X obedecem seguinte lei:2dsen =, onde o comprimento de onda do feixe monocromtico de radiao X incidente sobre aamostra, o ngulo no qual se observa interferncia de onda construtiva e d oespaamento entre as camadas de tomos na amostra. Ao se incidir raios X de comprimento de onda de 154 pm sobre uma amostra de um metaloide,cuja cela unitria segue a representao da figura abaixo, observa-se interferncia construtivaem 13,3. Tabela 1 Tabela 2 sen Metaloide Raio Atmico (pm) 7,23 0,1259 Si 117 11,2 0,1942 Ge 123 13,3 0,2300 As 125 15,0 0,2588 Te 143 30,0 0,5000 Po 167 De acordo com as tabelas 1 e 2, pode-se afirmar que o metaloide analisado :
[IME - 2011/2012 - 1 FASE] Sobre um sol, tambm chamado por muitos de soluo coloidal, pode-se afirmarque:
[IME - 2011/2012 - 1 FASE] Ao se adicionar um slido X em um bquer contendo soluo aquosa de fenolftalena, a soluo adquire uma colorao rsea e ocorre a liberao de um composto gasoso binrio. A anlise elementar desse composto gasoso revelou que a percentagem em massa de um de seus elementos superior a 90%. Com base nessas informaes, o slido X :
[IME - 2011/2012 - 1 FASE] Um volume V1 de oxignio e um volume V2 de cido sulfdrico, ambos nas mesmas condies de temperatura e presso, so misturados. Promovendo-se a reao completa, verifica-se que os produtos da reao, quando colocados nas condies iniciais de presso e temperatura, ocupam um volume de 10 L. Considere que a gua formada encontra-se no estado lquido e que as solubilidades dos gases em gua so desprezveis. Sabendo-se que havia oxignio em excesso na reao e que V1 +V2 = 24 L, verifica-se que o valor de V2 :
[IME - 2011/2012 - 1 FASE] Dos compostos abaixo, aquele que no forma ligao peptdica :
[IME - 2011/2012 - 1 FASE] A determinada profundidade, o organismo de um mergulhador absorve N2a uma presso parcial de 5,0 atm. Considere que a solubilidade do N2no sangue, a uma presso parcial de 0,78 atm, seja 5,85 x 10-4mol/L.Admita, ainda, que o volume total de sangue no corpo do mergulhador possa ser estimado em 6,0 L. Nessas condies, estima-se que a quantidade de N2, em mol, que o mergulhador elimina em seu retorno superfcie, onde a presso parcial desse gs 0,78 atm, seja:
[IME - 2011/2012 - 1 FASE] Dada a reao qumica abaixo, que ocorre na ausncia de catalisadores, pode-se afirmar que:
(IME - 2011/2012 - 2 FASE) Encontram-se em destaque cinco termos ou expresses. Assinale a alternativa correspondente ao termo cujo emprego est INCORRETO. Whether you are interested in reconnecting with friends, and wish to organize a class reunion, the Alumni Relations team is here to help.
[IME - 2011/2012 - 1 FASE] A figura apresenta o esquema de um telescpio refletor composto de: um espelho esfrico de Gauss com distncia focal ; um espelho plano inclinado 45 em relao ao eixo principal do espelho esfrico e disposto a uma distncia do vrtice do espelho esfrico, sendo ; uma lente ocular delgada convergente com distncia focal , disposta a uma distncia b do eixo do espelho esfrico. Para que um objeto no infinito, cujos raios luminosos so oblquos ao eixo ptico do espelho esfrico, apresente uma imagem final focada nas condies usuais de observao (imagem da ocular no seu plano focal), o valor de b deve ser:
(IME - 2011/2012 - 2 FASE) Leia os excertos e marque a opo com a resposta correta. Mars was warm enough to sustain lakes three billion years ago during the Hesperian Epoch, a period that was previously thought to be too cold and arid to sustain water on the surface, suggested a research published this January in the journal Geology. Dr Nicholas Warner, from the Department of Earth Science Engineering, said: Most of the research on Mars has focused on its early history and the recent past. Scientists had largely overlooked the Hesperian Epoch as it was thought that Mars was then a frozen wasteland. Excitingly, our study now shows that this middle period in Mars history was much more dynamic than we previously imagined. The meaning of overlook in the passage is
(IME - 2011/2012 - 2 FASE) Leia os excertos e marque a opo com a resposta correta. Mars was warm enough to sustain lakes three billion years ago during the Hesperian Epoch, a period that was previously thought to be too cold and arid to sustain water on the surface, suggested a research published this January in the journal Geology. Dr Nicholas Warner, from the Department of Earth Science Engineering, said: Most of the research on Mars has focused on its early history and the recent past. Scientists had largely overlooked the Hesperian Epoch as it was thought that Mars was then a frozen wasteland. Excitingly, our study now shows that this middle period in Mars history was much more dynamic than we previously imagined. Which of the following alternatives is WRONG, according to the passage?
(IME - 2011/2012 - 2 FASE) Leia os excertos e marque a opo com a resposta correta. On the mountain slopes south of Pompeii, a group of Roman citizens flee the doomed city, leaving their footprints in a layer of volcanic ash. Two thousand years later the footprints are rediscovered, and a joint Anglo-Italian dig is set up. Eminent Oxford archaeologist, Professor Julian Lockhart, unearths an exciting finding, but then he vanishes mysteriously. English detectives Nick Roberts and Lucia Fabri go out to assist the Italian police with the investigation, unaware of the sinister forces both human and natural that lie in wait for them. Their subsequent race for survival sweeps them up in an eerie reenactment of historical events. The passage can most probably be found in
(IME - 2011/2012 - 2 FASE) Leia o texto seguinte e complete as lacunas com a palavra ou expresso correta de acordo com o espaamento 03. Atmospheric Physics is the study of physical processes in the atmosphere; understanding the climate and the weather, and the physical reasons ____01______ it is as it is and how it might change in the future. My own particular research background is in radiative transfer and ____02______ I mean the transport of electromagnetic radiation through the atmosphere; _____03_____ the Suns radiation coming in, getting absorbed and scattered in the air, and the transfer of heat radiation emitted by the Earths surface. From a _____04_____ physics perspective theres an awful lot of things about the atmosphere that we dont understand, and of course, its very classical physics in the ____05______ that its looking at fluid dynamics and thermodynamics applied to the natural environment. What motivates us really is to try and explain what we see in the environment, what _____06_____ it and what might change it in the future, both in _____07_____ of local weather but also climate, by _____08_____ I mean larger areas and larger timescales. My background has led me to an interest in how solar radiation _____09_____ in the atmosphere, so ____10______ at how changes in the Sun might affect the climate for the past year.