giới thiệu đến bạn IELTS Academic Reading Sample 98 - Helium’s Future Up In The Air nhằm giúp các bạn có tài liệu ôn tập, luyện tập nhằm nắm vững được những kiến thức, kĩ năng cơ bản, đồng thời vận dụng kiến thức để giải các bài tập đề thi một cách thuận lợi. Chúc các bạn thi tốt! | You should spend about 20 minutes on Questions 27 40 which are based on Reading Passage 98 below. HELIUM S FUTURE UP IN THE AIR A In recent years we have all been exposed to dire media reports concerning the impending demise of global coal and oil reserves but the depletion of another key nonrenewable resource continues without receiving much press at all. Helium an inert odourless monatomic element known to lay people as the substance that makes balloons float and voices squeak when inhaled could be gone from this planet within a generation. B Helium itself is not rare there is actually a plentiful supply of it in the cosmos. In fact 24 per cent of our galaxy s elemental mass consists of helium which makes it the second most abundant element in our universe. Because of its lightness however most helium vanished from our own planet many years ago. Consequently only a miniscule proportion to be exact remains in earth s atmosphere. Helium is the byproduct of millennia of radioactive decay from the elements thorium and uranium. The helium is mostly trapped in subterranean natural gas bunkers and commercially extracted through a method known as fractional distillation. C The loss of helium on Earth would affect society greatly. Defying the perception of it as a novelty substance for parties and gimmicks the element actually has many vital applications in society. Probably the most well known commercial usage is in airships and blimps non- flammable helium replaced hydrogen as the lifting gas du jour after the Hindenburg catastrophe in 1932 during which an airship burst into flames and crashed to the ground killing some passengers and crew . But helium is also instrumental in deep-sea diving where it is blended with nitrogen to mitigate the dangers of inhaling ordinary air under high pressure as a cleaning agent for rocket engines and in its most prevalent use as a coolant for superconducting magnets in hospital MRI magnetic resonance imaging scanners. D The .
