用兩種物質(zhì)標(biāo)定NaOH溶液的濃度(單位為mol∙L-1)得如下結(jié)果:
A、0.09785,0.09790,0.09710,0.09895
B、0.09710,0.09795,0.09785,0.09700,0.09705
試問這兩組數(shù)據(jù)之間是否存在顯著性差異(P=95%)?
計算題:
分析某試樣中鐵含量的質(zhì)量分?jǐn)?shù),數(shù)據(jù)如下37.45%、37.20%、37.25%、37.30%、37.50%,求結(jié)果的平均值、極差、平均偏差、相對平均偏差、標(biāo)準(zhǔn)偏差、相對標(biāo)準(zhǔn)偏差。
37.34%、0.30%、0.11%、0.29%、0.13%、0.35%
不對。應(yīng)將原始試樣全部送交分析部門,再由分析人員對原始試樣采用四分法進(jìn)行縮分,依據(jù)經(jīng)驗公式取樣,再分解、測定等。