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Which statement describes evidence of a chemical reaction? a) ice melting eliminate b) water boiling c) lighting a match d) grape juice freezing

Select the correct answer how does the heat content of the reaction change in the process of photosynthesis when a glucose molecule is formed? ca the value of is negative the value of qis positive the value of a remains constant the value of a decreases the value of equals zero e

Ahydrogen atom has 1 electron. how many bonds can hydrogen form? a) 1 b) 2 c) 3 d) 4 e) 5