Lütfen yardım edin acelem varda​

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?

In which region is the substance in both the solid phase and the liquid phase? 1 2. 3 4 mark this and return save and exit next

How many grams are in one mole of lead?