问题
选择题
—What's this in English?
—_____ a pencil.[ ]
A. This is
B. Its
C. It's
D. Is
答案
答案:C
—What's this in English?
—_____ a pencil.[ ]
A. This is
B. Its
C. It's
D. Is
答案:C
取MnO2和KClO3的固体混合物25g,加热至恒重.在一定温度下,将残留的固体加入12g水中,有12g固体未溶,再加入5g水,仍有10g固体未溶,KCl在不同温度下的溶解度见下表.求原混合物中可能含有KClO3的质量.
温度(℃) | 0 | 20 | 40 | 60 | 80 | 100 |
溶解度(g/100g水) | 28.0 | 34.4 | 40.3 | 45.8 | 51.1 | 56.3 |