问题
解答题
|
答案
(1)60+55×2
=60+110
=170;
(2)90-90÷5
=90-18
=72;
(3)720÷8×9
=90×9
=810;
(4)18×(100-72)
=18×28
=504;
(5)(85+67)÷38
=152÷38
=4;
(6)200-(48-29)
=200-19
=181.
|
(1)60+55×2
=60+110
=170;
(2)90-90÷5
=90-18
=72;
(3)720÷8×9
=90×9
=810;
(4)18×(100-72)
=18×28
=504;
(5)(85+67)÷38
=152÷38
=4;
(6)200-(48-29)
=200-19
=181.
某温度时,在2L密闭容器中气态物质CO和H2反应生成气态物质Z,它们的物质的量随时间的变化如下表所示.
t/min | CO/mol | H2/mol | Z/mol |
0 | 1.00 | 1.00 | 0.00 |
1 | 0.90 | 0.80 | 0.10 |
3 | 0.75 | 0.50 | 0.25 |
5 | 0.65 | 0.30 | 0.35 |
7 | 0.55 | 0.10 | 0.45 |
9 | 0.55 | 0.10 | 0.45 |
10 | 0.55 | 0.10 | 0.45 |
(2)体系中发生反应的化学方程式是______.
(3)在3-5min时间内产物Z的平均反应速率:______.