Noble gases (except for he) have electron(s) in their valence shell. a. 1 b. 2 c. 4 d. 8

An alloy contains 66 g of pure zinc. what is the percentage of zinc in the alloy? express your answer to two significant figures and include the appropriate units.

Which of the following describes the entropy change as a solution is made from a liquid and solid

Pl what kind of reaction is this? nahco3 + h2o → co2 + naoh + h2o -composition -decomposition -single replacement -double replacement im leaning more toward single replacement. if im wrong can you explain whyy?