What is the ionic compound formed between ca+2 and so3-2

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?

40dm3 of gas at 760 torr are heated from 5°c to 50°c what is the new volume

In one or two grammatically correct sentences, write a definition for the term molecule geometry