【題目】某興趣小組利用家中的材料研究影響物質(zhì)溶解性的因素,實(shí)驗(yàn)步驟設(shè)計(jì)如下:
Ⅰ.稱取六份冰糖和一份食鹽,每10g為一份,并將其中五份冰糖研磨成粉末.
Ⅱ.按照下表進(jìn)行實(shí)驗(yàn)(實(shí)驗(yàn)所需儀器略)
第一組 | 第二組 | 第三組 | 第四組 | ||||
實(shí)驗(yàn)溫度 | 20℃ | 20℃ | 20℃ | 20℃ | 20℃ | 20℃ | 80℃ |
固體種類 | 冰糖 | 冰糖 | 冰糖(粉末) | 冰糖(塊狀) | 冰糖 | 食鹽 | 冰糖 |
固體質(zhì)量 | 10g | 10g | 10g | 10g | 10g | 10g | 10g |
溶劑種類 | 水 | 植物油 | 水 | 水 | 水 | 水 | 水 |
溶劑質(zhì)量 | 50g | 50g | 10g | 10g | 10g | 10g | 10g |
請(qǐng)你對(duì)他們的實(shí)驗(yàn)設(shè)計(jì)進(jìn)行分析:
(1)根據(jù)上述設(shè)計(jì),你認(rèn)為他們準(zhǔn)備研究的影響因素是________________________________,其中不影響物質(zhì)溶解性的因素是________________________________________.
(2)根據(jù)第四組實(shí)驗(yàn)與前三組實(shí)驗(yàn)的比較,你可以得到的結(jié)論是________________________.
(3)你認(rèn)為第四組實(shí)驗(yàn)的設(shè)計(jì)是否會(huì)影響實(shí)驗(yàn)結(jié)論的得出,請(qǐng)簡(jiǎn)述理由:________________________________________________________________.
【答案】(1)固體種類、溶質(zhì)顆粒的大小、溫度、溶劑種類、溶劑質(zhì)量 溶質(zhì)顆粒的大小、溶劑質(zhì)量
(2)溫度升高溶解速率加快
(3)不會(huì)影響,第四組可以與第二組或第三組中的冰糖溶解情況進(jìn)行比較
【解析】(1)通過對(duì)實(shí)驗(yàn)設(shè)計(jì)表格的分析,重點(diǎn)是觀察四組實(shí)驗(yàn)的條件發(fā)現(xiàn)探究的問題,主要有溫度的改變,物質(zhì)種類的改變,溶質(zhì)狀態(tài)的改變,溶劑質(zhì)量的改變等,由于物質(zhì)的溶解性是物質(zhì)本身的一種屬性,不受外界干擾,所以溶質(zhì)的狀態(tài)、溶劑的質(zhì)量對(duì)物質(zhì)溶解性無影響.
(2)物質(zhì)由塊狀改為粉末狀,會(huì)加快同一物質(zhì)的溶解速率,使實(shí)驗(yàn)時(shí)間變短.
(3)第四組實(shí)驗(yàn)相對(duì)于第二組和第三組,主要是溫度的改變,不會(huì)影響結(jié)論的得出.
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