化学与生活密切相关.下列生活中常见物质的俗名与化学式相对应的是( )
A:苏打﹣﹣NaHCO3
B:胆矾﹣﹣ZnSO4
C:酒精﹣﹣C2H5OH
D:生石灰﹣﹣Ca(OH)2
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Our warming planet is expected to face serious water crisis(危机)in the coming decades — which means each nation's natural resource will be more important than ever.
若分式x-2x-1的值为0,则x的值为( )