Physics, 28.11.2019 22:31 61497

The african bombardier beetle stenaptinus insignis can emit a jet of defensive spray from the moveable tip of its abdomen. the beetle's body has reservoirs of two different chemicals; when the beetle is disturbed, these chemicals are combined in a reaction chamber, producing a compound that is warmed from 20°c to 100°c by the heat of reaction. the high pressure produced allows the compound to be sprayed out at speeds up to 19m/s (68km/h), scaring away predators of all kinds. (the beetle shown in the figure is tethered to a wire fastened to its back by wax. it is responding to having its left foreleg pinched by forceps. the beetle is 2cm long.)calculate the heat of reaction of the two chemicals. assume that the specific heat capacity of the two chemicals and the spray is the same as that of water, 4.19×10³ j/kg⋅k, and that the initial temperature of the chemicals is 20°c.

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The african bombardier beetle stenaptinus insignis can emit a jet of defensive spray from the moveab...

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