Which of these types of changes is a physical change? A. Changing one substance into another
B. Dissolving one substance in another
C. Breaking apart one substance into two substances
D. Making a new substance

introduction of a drug directly into the respiratory tract is a form of inhalation administration.

they vary. it used to be meat, grain, bread, candy, beverages, donuts, and fruits/vegetables. now they added exercise in.

a is the correct answer

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.