Which of the following processes would you classify as chemical reactions（）
A. The burning of paper
B. The formation of rust on iron
C. The boiling of water
D. The preparation of sugar syrup by adding sugar to hot water
E. The manufacture of salt by evaporation of sea water
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Which of the following properties can be classified as the physical properties of a substance（）
A. hardness
B. density
C. solubility
D. ductility
E. malleability
F. melting point
G. boiling point
H. crystalline form
I. mass
J:volume
“游离氧”的英语词汇是______（）
A. free oxygen
B. nitrogen fixation
C. by-product
D. the amount of proteins
以下选项中表示“物理性质”的词汇是_____（）
A. physical property
B. chemical property
C. solid substance
D. melting point
William Shakespeare lived in the era when ____ reigned（）
A. Queen Elizabeth I
B. Queen Elizabeth II
C. Queen Victoria
D. None of the above
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