Which of the following pairs of elements would have similar properties and why? a. potassium and bromine b. chlorine and carbon c. magnesium and calcium d. flourine and neon

An exothermic reaction is conducted in an insulated calorimeter filled with water. the calorimeter is then sealed so that there is no heat exchanged between the contents of the container and the surrounding air. which of the following statements is true about the reaction?

When balancing a chemical equation:

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