What is the concentration of a pH 4.2 solution of HCl

The electron configurations of two different atoms are shown below. each yellow electron has a charge of 1−, and the net charge of each nucleus is shown. these atoms will combine with bond. a. an ionic b. a positive c. a negative d. a covalent plzzz mee with !

How have the greenhouse gasses increased from the year 2000 to 2018

If we compare and contrast electromagnetic waves with sound waves, all but one statement is true. that is a) sound waves require a medium to travel while electromagnetic waves do not. b) electromagnetic waves can travel through the vacuum of space while sound waves cannot. c) electromagnetic waves must have a medium in which to travel, but sound waves can travel anywhere. eliminate d) sound waves must bounce off of matter in order to travel while electromagnetic waves do not require matter to be present.