What is the charge of a particle having nine protons and 10 electrons?

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?

Describe the properties of sodium, chlorine, and sodium chloride

Which of the following is not a characteristic of s waves?