Foram encontradas 51 questões.
Uma amostra de óxido de níquel não estequiométrico contém 77,70% de Ni em massa e defeitos intrínsecos em sua estrutura. Levando em consideração que esta amostra possui uma estrutura cristalina cúbica de face centrada, com parâmetro de rede de 4,180 Å e densidade determinada experimentalmente de 6526 kg.m-3, assinale a alternativa correta. (Dados: MM(Ni) = 58,6934 g.mol-1, MM(O) = 15,999 g.mol-1)
Provas
Considere um catalisador heterogêneo do tipo MOF (metal-organic framework) quiral utilizado em reações enantiosseletivas. Levando em consideração que as reações ocorrem não só sobre a superfície do material, mas também dentro de seus poros, analise as seguintes afirmações:
I. As reações enantiosseletivas utilizando este tipo de material provavelmente devem ser mais lentas do que as reações em solução correspondentes, já que os reagentes têm maior dificuldade para acessar os sítios ativos.
II. O confinamento dos sítios ativos pode aumentar a enantiosseletividade quando comparado à reação em solução, e este efeito deve aumentar à medida que o tamanho de poro aumenta.
III. O confinamento dos sítios ativos pode aumentar a enantiosseletividade quando comparado à reação em solução, e este efeito deve diminuir à medida que o tamanho de poro aumenta.
É correto afirmar que
Provas
No difratograma de raios X de pó de uma amostra de um material do tipo MCM mesoporoso com poros de diâmetro de 30 Å, obtido utilizando radiação com comprimento de onda 1,54 Å, o primeiro pico aparece em 2θ = 2,2°. Considerando que um material hexagonal possui a = b ≠ c, α = β = 90°, γ = 120°, qual é a espessura aproximada das paredes do material? (Dados: sen 1,1 = 0,02, sem 60 = 0,87).
Provas
O craqueamento catalítico fluido (FCC, do inglês Fluid Catalytic Cracking) é um dos processos mais importantes utilizados nas refinarias de petróleo, e emprega zeólitas como componentes dos catalisadores. Entre as várias propriedades da zeólitas, a acidez é um fator que tem grande influência sobre a sua atividade catalítica. A respeito da acidez desses materiais, assinale a alternativa correta.
Provas
- FundamentosPropriedades das Substâncias
- Química InorgânicaGeometria Molecular, Polaridade e Forças Intermoleculares
I. O padrão de difração de uma amostra policristalina pode ser utilizado para identificar as diferentes fases cristalinas presentes nela.
II. Para amostras policristalinas de nanopartículas, quanto mais largos os picos de difração, maior será o tamanho médio das nanopartículas.
III. A posição de um pico de difração (2θ) é independente da fonte de radiação utilizada.
É correto afirmar que
Provas
Choose the best alternative: “Brazilians’ sense of belief in institutions .”
Provas
Choose the best alternative: “People have changed to virtual political protests, ?”
Provas
Leia atentamente o texto a seguir e responda às questões de 17 a 24.
04.08.2024
‘We have reached the limit.’ Clash with Elon Musk prompts calls for social media controls in Brazil
London (CNN) — Brazil’s attorney general has called for social media platforms in the country to be regulated after Elon Musk threatened to disobey a court order banning certain accounts on X and lashed out against “aggressive censorship.”
In a post on X Sunday, Attorney General Jorge Messias wrote: “It is urgent to regulate social networks. We cannot live in a society in which billionaires domiciled abroad have control of social networks and put themselves in a position to violate the rule of law, failing to comply with court orders and threatening our authorities.”
In a statement, Brazil’s Supreme Court described Musk’s defiance as a “flagrant” obstruction of justice and said he should be investigated by the police. Supreme Court Justice Alexandre de Moraes announced Sunday that he would open an inquiry into the billionaire businessman who owns X.
The standoff is the latest clash between authorities around the world and Musk – a self-declared “free speech absolutist” who has relaxed X’s content moderation policies and reinstated a number of previously blocked accounts after buying the company, formerly known as Twitter, in 2022.
Orlando Silva, a Brazilian lawmaker aligned with the country’s left-wing government, said he would propose a “responsibilities regime for these digital platforms.” “We have reached the limit!” he posted on X, adding that Musk had disrespected the judiciary.
On Saturday, X’s global government affairs team posted that it had been “forced by court decisions to block certain popular accounts in Brazil” and threatened with “daily fines” for non-compliance.
“We do not know which posts are alleged to violate the law. We are prohibited from saying which court or judge issued the order, or on what grounds,” they wrote. They do not believe the orders are constitutional and will challenge them legally where possible, they added.
The Supreme Court had ordered that the accounts be blocked as part of its ongoing investigation into “digital militias,” which, among other things, is looking into the spread of misinformation and incitement of crime under the government of former far-right President Jair Bolsonaro.
Social media platforms have been widely viewed as a catalyst for riots in Brazil that took place on January 8 last year, when hundreds of protesters broke into federal government buildings in the capital Brasilia, in scenes reminiscent of the January 6, 2021, insurrection in the United States.
Musk suggested that Moraes was behind the ban, writing Sunday on X that the judge had “brazenly and repeatedly betrayed the constitution and people of Brazil. He should resign or be impeached.”
In a separate post Saturday, he called the court’s decision to block the accounts “aggressive censorship” that “appears to violate the law and will of the people of Brazil.” He said X would defy the court’s order and lift all restrictions.
“As a result, we will probably lose all revenue in Brazil and have to shut down our office there. But principles matter more than profit,” he noted.
X has faced criticism for accommodating government censorship demands in the past, with Musk saying the company has no choice but to comply. For example, it blocked some X accounts in Turkey at the behest of the government ahead of the country’s elections last year, while at the same time contesting the orders in court.
(Internet: <https://edition.cnn.com/2024/04/08/tech/elon-musk-brazil-investigation/index.html> )
In “As a result, we will probably lose all revenue in Brazil and have to shut down our office there. But principles matter more than profit”, it is not possible to say that Musk
Provas
Leia atentamente o texto a seguir e responda às questões de 17 a 24.
04.08.2024
‘We have reached the limit.’ Clash with Elon Musk prompts calls for social media controls in Brazil
London (CNN) — Brazil’s attorney general has called for social media platforms in the country to be regulated after Elon Musk threatened to disobey a court order banning certain accounts on X and lashed out against “aggressive censorship.”
In a post on X Sunday, Attorney General Jorge Messias wrote: “It is urgent to regulate social networks. We cannot live in a society in which billionaires domiciled abroad have control of social networks and put themselves in a position to violate the rule of law, failing to comply with court orders and threatening our authorities.”
In a statement, Brazil’s Supreme Court described Musk’s defiance as a “flagrant” obstruction of justice and said he should be investigated by the police. Supreme Court Justice Alexandre de Moraes announced Sunday that he would open an inquiry into the billionaire businessman who owns X.
The standoff is the latest clash between authorities around the world and Musk – a self-declared “free speech absolutist” who has relaxed X’s content moderation policies and reinstated a number of previously blocked accounts after buying the company, formerly known as Twitter, in 2022.
Orlando Silva, a Brazilian lawmaker aligned with the country’s left-wing government, said he would propose a “responsibilities regime for these digital platforms.” “We have reached the limit!” he posted on X, adding that Musk had disrespected the judiciary.
On Saturday, X’s global government affairs team posted that it had been “forced by court decisions to block certain popular accounts in Brazil” and threatened with “daily fines” for non-compliance.
“We do not know which posts are alleged to violate the law. We are prohibited from saying which court or judge issued the order, or on what grounds,” they wrote. They do not believe the orders are constitutional and will challenge them legally where possible, they added.
The Supreme Court had ordered that the accounts be blocked as part of its ongoing investigation into “digital militias,” which, among other things, is looking into the spread of misinformation and incitement of crime under the government of former far-right President Jair Bolsonaro.
Social media platforms have been widely viewed as a catalyst for riots in Brazil that took place on January 8 last year, when hundreds of protesters broke into federal government buildings in the capital Brasilia, in scenes reminiscent of the January 6, 2021, insurrection in the United States.
Musk suggested that Moraes was behind the ban, writing Sunday on X that the judge had “brazenly and repeatedly betrayed the constitution and people of Brazil. He should resign or be impeached.”
In a separate post Saturday, he called the court’s decision to block the accounts “aggressive censorship” that “appears to violate the law and will of the people of Brazil.” He said X would defy the court’s order and lift all restrictions.
“As a result, we will probably lose all revenue in Brazil and have to shut down our office there. But principles matter more than profit,” he noted.
X has faced criticism for accommodating government censorship demands in the past, with Musk saying the company has no choice but to comply. For example, it blocked some X accounts in Turkey at the behest of the government ahead of the country’s elections last year, while at the same time contesting the orders in court.
(Internet: <https://edition.cnn.com/2024/04/08/tech/elon-musk-brazil-investigation/index.html> )
From the sentence “Social media platforms have been widely viewed as a catalyst for riots in Brazil that took place on January 8 last year, when hundreds of protesters broke into federal government buildings in the capital Brasilia, in scenes reminiscent of the January 6, 2021, insurrection in the United States”, it is possible to say that
Provas
Leia atentamente o texto a seguir e responda às questões de 17 a 24.
04.08.2024
‘We have reached the limit.’ Clash with Elon Musk prompts calls for social media controls in Brazil
London (CNN) — Brazil’s attorney general has called for social media platforms in the country to be regulated after Elon Musk threatened to disobey a court order banning certain accounts on X and lashed out against “aggressive censorship.”
In a post on X Sunday, Attorney General Jorge Messias wrote: “It is urgent to regulate social networks. We cannot live in a society in which billionaires domiciled abroad have control of social networks and put themselves in a position to violate the rule of law, failing to comply with court orders and threatening our authorities.”
In a statement, Brazil’s Supreme Court described Musk’s defiance as a “flagrant” obstruction of justice and said he should be investigated by the police. Supreme Court Justice Alexandre de Moraes announced Sunday that he would open an inquiry into the billionaire businessman who owns X.
The standoff is the latest clash between authorities around the world and Musk – a self-declared “free speech absolutist” who has relaxed X’s content moderation policies and reinstated a number of previously blocked accounts after buying the company, formerly known as Twitter, in 2022.
Orlando Silva, a Brazilian lawmaker aligned with the country’s left-wing government, said he would propose a “responsibilities regime for these digital platforms.” “We have reached the limit!” he posted on X, adding that Musk had disrespected the judiciary.
On Saturday, X’s global government affairs team posted that it had been “forced by court decisions to block certain popular accounts in Brazil” and threatened with “daily fines” for non-compliance.
“We do not know which posts are alleged to violate the law. We are prohibited from saying which court or judge issued the order, or on what grounds,” they wrote. They do not believe the orders are constitutional and will challenge them legally where possible, they added.
The Supreme Court had ordered that the accounts be blocked as part of its ongoing investigation into “digital militias,” which, among other things, is looking into the spread of misinformation and incitement of crime under the government of former far-right President Jair Bolsonaro.
Social media platforms have been widely viewed as a catalyst for riots in Brazil that took place on January 8 last year, when hundreds of protesters broke into federal government buildings in the capital Brasilia, in scenes reminiscent of the January 6, 2021, insurrection in the United States.
Musk suggested that Moraes was behind the ban, writing Sunday on X that the judge had “brazenly and repeatedly betrayed the constitution and people of Brazil. He should resign or be impeached.”
In a separate post Saturday, he called the court’s decision to block the accounts “aggressive censorship” that “appears to violate the law and will of the people of Brazil.” He said X would defy the court’s order and lift all restrictions.
“As a result, we will probably lose all revenue in Brazil and have to shut down our office there. But principles matter more than profit,” he noted.
X has faced criticism for accommodating government censorship demands in the past, with Musk saying the company has no choice but to comply. For example, it blocked some X accounts in Turkey at the behest of the government ahead of the country’s elections last year, while at the same time contesting the orders in court.
(Internet: <https://edition.cnn.com/2024/04/08/tech/elon-musk-brazil-investigation/index.html> )
Choose the alternative that better substitutes the underlined preposition in “On Saturday, X’s global government affairs team posted that it had been ‘forced by court decisions to block certain popular accounts in Brazil’ and threatened with ‘daily fines’ for non-compliance”.
Provas
Caderno Container