几道关于分子原子的化学题.

题目

几道关于分子原子的化学题.
1.葡萄糖是不是化合物?
2.下列哪一项是均匀混合物?
A.佳得乐 B.硫 C.葡萄糖 D.士力架
3.0.00160用科学计数法表示
A.1.6 x 10-3 B.1.60 x 10-3
4.7.50*6.00等于多少?
A.45 B.45.0
5.(1)某糖质量为27.7克,其中糖占15%,求糖的质量为多少?
a) 4.16 g b) 4.2 g
(2)这些糖为多少盎司?
a) 0.146 oz b) 0.15 oz
6.质量和体积分别为19.754 g和14.6 ml 的物体,密度是多少?
a) 1.3530 g/ml b) 1.35 g/ml
7.下列哪项可以准确地描述二氧化碳?
a.单原子 b.双原子 c.同原子 d.杂原子
还有三道题实在不会翻译,麻烦看一下英文.
1.a game of darts,the darts are scattered across the board.The thrower was()
a) accurate not precise b) precise not accurate
c) accurate and precise d) not accurate or precise
2.During a game of darts,all three darts hit high and left.The thrower was()
a) accurate not precise b) precise not accurate
c) accurate and precise d) not accurate or precise
3.20.During a game of darts,all three darts were close to the bullseye.The thrower was()
a) accurate not precise b) precise not accurate
c) accurate and precise d) not accurate or precise

答案

1、是 有机化合物2、A B.硫 C.葡萄糖是纯净物 D.士力架是混合物,但不均匀3、B 0.00160的最后那个零不可省略0.00160的有效数字是3个,所以为了保持一致选择B.1.60 x 10-3,它的有效数字也是3个4、B 7.50和6.00的有效数...