【题目】为了进一步增强洗衣粉对血渍、奶渍、油污、土豆泥等衣物上常见污垢的去除能力,洗衣粉中常常会添加各种酶类。请回答有关问题:
(1)根据衣物上常见的污垢,加酶洗衣粉中添加的酶类有碱性蛋白酶、 、 和 等四类。
(2)碱性蛋白酶能将血渍、奶渍等含有的大分子蛋白质水解成可溶性的 。
(3)下图为加酶洗衣粉的包装袋上的产品说明,根据你所学习的有关知识,解释注意事项③的原因 。
注意事项 |
①请将本品置于阴凉、干燥处,避热、避湿、避光。 ②不慎溅入眼中,立即用水冲洗。 ③水温以30~50℃为宜,切忌用70℃以上的热水。 |
(4)下面是添加脂肪酶的加酶洗衣粉和普通洗衣粉洗涤效果的有关探究实验,请据表回答:
组别 | 洗涤物(等量) | 洗涤温度 | 洗衣粉(等量) | 水量 | 洗净所需时间 |
1 | 油污布 | 45℃ | 加酶 | 2L | 4 min |
2 | 油污布 | 45℃ | 普通 | 2L | 7 min |
3 | 油污布 | 5℃ | 加酶 | 2L | 9 min |
4 | 油污布 | 5℃ | 普通 | 2L | 8 min |
①该实验设计体现了 原则。
②若1号实验组洗净所需时间接近7分钟,请分析最可能的原因 。
(5)添加蛋白酶的加酶洗衣粉不适宜洗涤下列哪些衣料 。
①棉织品
②毛织品
③腈纶织品
④蚕丝织品
⑤涤纶织品
⑥锦纶织品
【答案】
(1)(碱性)脂肪酶 淀粉酶 纤维素酶
(2)多肽(氨基酸)
(3)酶的催化受温度影响,30~50℃是洗衣粉中的酶的适宜温度范围
(4)①单一变量、对照(答对一项即可) ②洗衣粉中的酶变性或失效(答案合理即可)
(5)②④
【解析】
(1)加酶洗衣粉中添加的酶类有碱性蛋白酶、碱性脂肪酶、淀粉酶、纤维素酶等四类。
(2)碱性蛋白酶能将大分子蛋白质水解成可溶性的多肽。
(3)包装袋上注意事项③要求水温以30~50℃为宜,切忌用70℃以上的热水的原因酶的催化受温度影响,30~50℃是洗衣粉中的酶的适宜温度范围。
(4)①从表格中的自变量和因变量来看该实验设计体现了单一变量、对照原则。
②若1号实验组洗净所需时间接近7分钟,与2号对照说明酶已经失去了活性。
(5)蛋白酶可分解蛋白质,故毛织品、蚕丝织品等以蛋白质为主要成分的衣料不能用含蛋白酶的加酶洗衣粉洗涤。
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