(4) zinc Zinc is higher in the activity series than hydrogen, copper, gold, and silver
Answer: Option (4) is the correct answer. ;
The element that reacts spontaneously with 1.0 M HCl(aq) at room temperature is zinc, as it is more reactive than hydrogen. Other options like copper, silver, and gold do not react with hydrochloric acid. Therefore, the correct answer is option 4, zinc.
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