a membrane-bound organelle that contains DNA and has a role in the processes such as growth, metabolism and reproduction is called what

What is the value of keq for the reaction expressed in scientific notation

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?

Which is an example of a reversible physical change?