F2 IS 2nd Term WS08 Answers

10.4    Acids and corrosion

i      Words to know:

	English term	Write the words again	Chinese term
1	Corrode (vb)		腐蝕 (動詞)
2	Corrosion (n)		腐蝕 (名詞)
3	Corrosive (adj)		腐蝕性的
4	‘Pop’ sound		爆鳴聲
5	Hydrogen		氫
6	Marble		大理石
7	Limestone		石灰石
8	Calcium carbonate		碳酸鈣

i      Fill in the blanks:

1             Some metals (e.g. zinc and magnesium) react with dilute acids. During the reactions, hydrogen

gas and heat are produced. The metals decrease in size gradually. Thus acids have corrosive

effects on these metals.

2           To test for hydrogen, a burning splint is put near the mouth of the test tube containing the gas. It burns

with a ‘pop’ sound if the gas is hydrogen.

3             We should not use acidic detergents to clean marble / limestone and limestone / marble

surfaces because both of them contain calcium carbonate, which are easily

corroded by acids. The reaction gives out carbon dioxide.