the 760 mm Hg, what is the pressure of the gas? 12 State Boyle's law. A thread of mercury of length 15 cm is used to trap some air in a capillary tube with uniform cross-sectional area and closed at one end. With the tube vertical and the open end uppermost, the length of the trapped air column is 20 cm. Calculate the length of the air column, when the tube is held (i) horizontally (ii) vertically with the open end underneath. (Atmospheric pressure = 76 cm of mercury) (SSCE) 13 Describe an experiment to investigate the relationship between the pressure and the

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