1.To heat water in a test tube,we should fill_______of the test tube with water.
A.one-third(1/3)
B.half(1/2)
C.two-third(2/3)
D.three-forth(3/4)
2.When a Bunsen flame is not in use for a short while, you should close the air hole.This is to________.
A.prevent striking back.
B.change the colour of the flame to yellow.
C.make the flame luminous and visible.
D.make the flame irregular in shape.
Science questions
2013-10-30 4:13 am
回答 (3)
2013-10-30 7:15 am
✔ 最佳答案
1. Option B2. Option C
2013-10-30 5:33 pm
1. A (to prevent the hot water out of the test tube)
2. B (let others easily see the burner flame)
2013-10-30 09:36:46 補充：
Sorry !! Question 2 is C!!
2. B (let others easily see the burner flame)
2013-10-30 09:36:46 補充：
Sorry !! Question 2 is C!!
2013-10-30 5:39 am
1.C.two-third(2/3)
2.D.make the flame irregular in shape.
2.D.make the flame irregular in shape.
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