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例1 在一只盛有稀硫酸的烧杯中,漂浮着一木块,如图所示.往烧杯中加少量某种固体物质后,木块浸入液体中的体积变大(假设此过程中溶液的体积不变).加入的固体物质是( )A.ZnB.Ba(Mg)_2C.CuD.Ba(OH)_2分析木块处于漂浮状态,浮力的大小恰好等于物体所受重力.木块浸入液体的体积变大,说明该液体密度减小,在液体体积不变时,密度减小就是溶质质量减小,根据发生的化学反应,应选 D.
Example 1 In a beaker containing dilute sulphuric acid, a wooden block was floated as shown in the figure. After adding a small amount of certain solid material to the beaker, the volume of the block immersed in the liquid became larger (assuming that the solution in this process The volume is constant.) The solid material added is (A.ZnB.Ba(Mg)_2C.CuD.Ba(OH)_2. The analysis block is in a floating state. The buoyancy is exactly equal to the gravity of the object. The increase in the volume of the liquid indicates a decrease in the density of the liquid. When the volume of the liquid is constant, the decrease in density is a decrease in the mass of the solute. According to the chemical reaction that occurs, the liquid should be selected.