Round 3: Tossup 17

A thin coating of titanium dioxide on this material makes it superhydrophilic and allows for photocatalytic “self-cleaning.” This material (-5[1])is made to a uniform thickness over a molten tin bath in the Pilkington process, (-5[1])which produces this material’s “float” type. When manufacturing this material, soda and lime (10[1])are added to lower the melting temperature of its (10[1])main component (-5[1])to around 1600 (10[1])degrees Celsius. A low coefficient of thermal expansion is characteristic of this material’s “borosilicate” (10[1])type. (10[1])Fused quartz (10[2])is one type of this amorphous (10[1])material composed almost entirely of silicon dioxide. For 10 points, the melting of sand produces what material (10[1])sold by Pyrex? ■END■ (10[1])

ANSWER: glass [accept Pyrex glass; accept quartz glass; accept borosilicate glass; accept soda-lime glass; accept float glass; accept glasses; prompt on fused silica or silicon dioxide or SiO2 until “borosilicate” is read]
<Sheffield A, Chemistry> | Packet C
= Average correct buzz position

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