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Is an octopus dangerous to man?

There are stories of people being attacked by an octopus and frantically tying to detach the suckers of the encircling arms. This may happen very rarely and when it does the octopus is really investigating a new moving shape rather than attacking it. If the person could manage to keep perfectly still the octopus would soon let him go.

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If the density of gold is more than that of iron, why is gold softer than iron?

The softness of a metal is its ability to undergo permanent deformation under applied stress. All metals have specific crystalline structures. Each structure has its own densely packed crystalline planes. There exist line defects and plane defects in a crystal system. Such defects are more in densely packed crystal systems, i.e., metallic crystals with higher density, and result in a …

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If noble gases are supposed to be inert and unreactive, how is krypton difluoride formed?

While krypton is generally an inert element, in extreme volatile conditions, it can form compounds in very small quantities. There are several ways that krypton can form its fluoride: by passing through an electrical arc, proton bombardment or photochemical process. All these processes require a very heavy amount of energy. Krypton has achieved a unique importance in science. In 1960, …

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If leaves get their colour from chlorophyll, what gives flowers their colour?

Plant cells have cell organelles known as plastids, which are colouring agents. There are three types of plastids – chloroplasts (contain green pigment chlorophyll), leucoplasts (white or colourless plastids) and chromoplasts (contain other pigments). All cells have varying proportions of these. Flowers have a majority of the third type and get their colours from these. From Wikipedia Chromoplasts are plastids …

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How Will our Sun Die?

Everything that is born must die. Not only living beings, but inanimate objects like stars too. The birth of a star The universe has massive clouds of hydrogen floating around. Sometimes, these clouds come together and form very dense and huge balls of hydrogen gas. As the clouds come close, their temperature increases. This is called a proto-star (original star). …

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How was Tutankhamen’s tomb discovered?

In November 1922 an English archaeologist, Howard Carter, found in Egypt the tomb of a pharaoh that was filled with wonderful, exciting treasure. Newspapers were full of stories of golden thrones, beds and chariots, of jeweled caskets, even of flowers still preserved in the dry, airless tomb. Carter, who was working for Lord Carnarvon, had been busy in the royal …

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