在常温下硫酸的密度与溶质的质量分数对照表如下： （1）由常温下硫酸的密度与溶质的质量分数对照表可以看出，常温下硫酸的密度随着溶质的质量分数的增大而增大．（2）设需98%的浓硫酸的质量为x，根据溶液稀释前后溶质的质量不变，250mL=250cm3，则1.14g/cm3×250cm3×20%1.84cm3×x×98%x≈31.6cm3=31.6mL．需再加水的质量是1.14g/cm3×250cm3-1.84cm3×31.6cm3≈226.9g（合226.9mL）．故答案为：（1）常温下硫酸的密度随着溶质的质量分数的增大而增大；（2）需98%的浓硫酸31.6mL；需再加水的体积是226.9mL．
硫酸密度与浓度对照表 (1) 最低0.27元开通文库会员，查看完整内容>；原发布者：园丁教育H2SO质量%15161718192021222324252627282930313233343536373839404142434445464748495051525354555657密度0℃e69da5e887aae799bee5baa6313334336265641.11161.11941.12721.13511.14301.15101.15901.16701.17511.18321.19141.19961.20781.21601.22431.23261.24091.24931.25771.26611.27461.28311.29171.30041.30911.31991.32681.33571.34471.35381.36301.37241.38191.39151.40121.41101.42091.43101.44121.45151.46191.47241.4830密度5℃1.10931.11701.12471.13251.14031.14811.15601.16401.17201.18001.18811.19621.20441.21261.22081.22911.23741.24571.25411.26251.27091.27941.28831.29661.30531.31411.3326密度10℃1.10691.11451.12211.12981.13751.14531.15311.16091.16881.17681.18481.19281.20101.20911.21731.22551.23381.24211.25041.25881.26721.27571.28431.29291.30161.31031.31911.32801.33701.34611.35531.36461.37401.38351.39311.40291.41281.42281.43291.44311.45351.46401.4746密度15℃1.10451.11201.11951.12711.13471.14241.15011.15791.16571.17361.18161.18961.19761.20571.21381.22201。.
硫酸的密度和溶质的质量分数对照表如下： 稀硫酸的质量=5000mL×1.14g/mL=5700g．设稀释成20%的稀硫酸时所用98%的浓硫酸的质量为x．x×98%5700g×20%x=1163.2g浓硫酸的体积=1163.3g 1.84gcm-3=632.2ml需要水的体积=5700g-1163.2g 1gcm-3=4536.8ml故答案为：632.2、4536.8．
