What is laughing gas made out of? (31 points so hurry up before someone else does) *free points*

When the volume and number of particles of a gas are constant which of the following is also constant

Water is important for the of cells. a: size, shape, and temperature b: temperature, color, and odor c: color, odor, and size d: shape, temperature, and color

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?