【单选题】下列属于吡唑酮类非甾体抗炎药的是( )。
【判断题】拆零药品记录应从开始拆零至销售完毕或有质量问题撤柜。
【单选题】过渡元素高价化合物在酸性条件下有较强的氧化性,如KMnO 4 、Na 2 WO 4 (钨酸钠)等,钨的最高价为+6价。现有钨酸钠晶体(Na 2 WO 4 ·2 H 2 O)0.990g加水溶解后,再加入一定量的 锌和稀H 2 SO 4 ,反应生成一种蓝色化合物(可看作含+5价、+6价混合价态的钨的氧化物)且无H 2 产生。现用0.044mol/L KMnO 4 酸性溶液滴定这种蓝色化合物恰好将其氧...
【单选题】At free-trade prices, a bicycle in country X sells for $100 when the per-unit cost of material inputs is $90. Country X has a nominal tariff rate of 15% on bicycles, and 10% on the material inputs. Ba...
【单选题】为消除可摘局部义齿不稳定,错误的方法是()。
【单选题】Assume a country that produces only cloth and paddy. Cloth production requires significant amounts of labor and capital, but relatively less land. Assume that paddy production requires relatively less...
A.
the production of both paddy and cloth will increase.
B.
the production of cloth will increase, but that of paddy will remain unchanged.
C.
the production of cloth will increase, but that of paddy will decline.
D.
the production of paddy will increase, but that of cloth will remain unchanged.
【简答题】已知:氧化性:KMnO 4 >HNO 3 ;Bi 元素+3价较稳定,NaBiO 3 溶液为无色。取一定量的Mn(NO 3 ) 2 溶液依次进 行下列实验,现象记录如下。 ①滴加适量的NaBiO 3 溶液,溶液变为紫红色。 ②继续滴加适量H 2 O 2 ,紫红色褪去,并有气泡产生。 ③再加入适量的PbO 2 固体,固体溶解,溶液又变为紫红色。 ④最后通入足量的SO 2 气体,请回答下列问题: (1)...