What role does each type of chemical play in the firework

Answer asap : ( a. how does mucus prevent the entry of pathogens? b. describe two ways white blood cells protect us from pathogens.

Which of the following is an indication that a substance has undergone a chemical change? a. no new product has been formed. b. the color of the substance has not changed. c. the original constitute has not changed. d. the molecular structure has changed.

If there are 3.5 moles of koh, how many moles of naoh can be produced? question 1 options: a)3.0 moles naoh b)3.5 moles naoh c)1 moles naoh d)9 moles naoh