In class, an instructor pours liquid nitrogen on an inflated balloon and the balloon collapsed on itself. why does the ballon deflate although no gas is lost from the balloon?

Which element is least likely to undergo a chemical reaction

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?

Draw the lewis structure for the trisulfur s3 molecule. be sure to include all resonance structures that satisfy the octet rule.