Sian wants to measure the number of seconds that it takes for the contents of a beaker to change from clear to purple. Which of these tools should she use for this purpose? an electronic balance a stopwatch a barometer a graduated cylinder

This is a characteristic of the elements in the periodic table that shows a pattern. it may increase or decrease across or down the table.

What is the percentage of hydrogen in nitrogen trihydride

Astable electron arrangement for an atom is one that does not easily change. how is this arrangement arrived at? a. valence electrons are transferred or shared to create a full outer shell of electrons. b. valence electrons are discarded into space to create a full outer shell of electrons. c. protons (positive charge) pair with valence electrons (negative charge) to create a strong bond. d. outer shells with valence electrons are transferred or shared.