How many chlorine atoms are there in 0.75 mol of carbon tetrachloride?

When a scientific theory has been tested and proved by the scientific community, it becomes a law

When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?

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