假定在SiO2中加入训(Na2O)=10%的Na2O，请计算氧与硅之比值。如果ω(O):ω(Si)≤2.5是玻璃化趋势的判据，则形成玻璃化的Na2O最大量是多少
参考答案：有ω(SiO2)=90%及ω(Na2O)=10%，故
ω(O):ω(Si)=(0.9×2+0.1):0.9=2.111
因为ω(O):ω(Si)=2.111＜2.5，故有良好的玻璃化形成的趋势。
设Na2O的最大含量为x，SiO2的含量=1-x，
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故[*]
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