Tenha acesso completo ao Stoodi

Assine o Stoodi e prepare-se para o ENEM com nossos conteúdos exclusivos!

Exercícios de Inglês

Listagem de exercícios

IME 2016

Text 2

MATERIALS OF IMPORTANCE

Carbonated Beverages

 

Containers One common item that presents some interesting material property requirements is the container for carbonated beverages. The material used for this application must satisfy the following constraints: provide a barrier to the passage of carbon dioxide, which is under pressure in the container; be nontoxic, unreactive with the beverage, and, preferably be recyclable; be relatively strong, and capable of surviving a drop from a height of several feet when containing the beverage; be inexpensive and the cost to fabricate the final shape should be relatively low; if optically transparent, retain its optical clarity; and capable of being produced having different colors and/or able to be adorned with decorative labels.

 

All three of the basic material types—metal (aluminum), ceramic (glass), and polymer (polyester plastic)—are used for carbonated beverage containers (as shown below). All of these materials are nontoxic and unreactive with beverages. In addition, each material has its pros and cons. For example, the aluminum alloy is relatively strong (but easily dented), is a very good barrier to the diffusion of carbon dioxide, is easily recycled, cools beverages rapidly, and allows labels to be painted onto its surface. However, the cans are optically opaque and relatively expensive to produce. Glass is impervious to the passage of carbon dioxide, is a relatively inexpensive material, and may be recycled, but it cracks and fractures easily, and glass bottles are relatively heavy. Whereas plastic is relatively strong, may be made optically transparent, is inexpensive and lightweight, and is recyclable, it is not as impervious to the passage of carbon dioxide as aluminum and glass. For example, you may have noticed that beverages in aluminum and glass containers retain their carbonization (i.e., “fizz”) for several years, whereas those in two-liter plastic bottles “go flat” within a few months.

Disponível em: https://metallurgyandmaterials.wordpress.com Acesso em: 29 jun. 2016.

 

Escolha a alternativa correta de acordo com o texto 2.

Conta de email não verificada

Não foi possível realizar o seu cadastro com a sua conta do Facebook pois o seu email não está confirmado no Facebook.

Clique aqui para ver como confirmar sua conta de email no Facebook ou complete seu cadastro por aqui.

Entendi
Clicando em "Criar perfil", você aceita os termos de uso do Stoodi.
Tem perfil no Stoodi? Fazer Login