Calculate the % change in pH when 4.052 g of solid NaOH (39.997 g/mol) is added to a 394 mL buffer solution of HX 0.57 M and NaX 0.31 M? Ka for HX is 2.0 x 10-5.

Problem page gaseous ethane reacts with gaseous oxygen gas to produce gaseous carbon dioxide and gaseous water . if of water is produced from the reaction of of ethane and of oxygen gas, calculate the percent yield of water. be sure your answer has the correct number of significant digits in it.

Plz choose one of the compounds from the table and explain how you know the numbers of atoms in your formula. is it possible for two different compounds to be made from the exact same two elements? why or why not? with a limited number of elements (less than 120 are known), does this mean we also have a small number of compounds or do we have a large number of compounds in this world?

Which statement accurately represents the arrangement of electrons in bohr’s atomic model?