Do a bucket water and a ice cube have the same chemical properties true or false

Word equation for k+ h2o yield koh + h2

How many moles are in 43.9 l of oxygen

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?