How does the human respiratory system brings air/oxygen from the environment into the blood (also known as inhaling!) Question options:

Air enters through your alveoli. It travels through the pharynx and trachea to the bronchi. In the mouth, air enters the lungs where oxygen is transferred into the bloodstream.

Air enters through your nose and mouth. It travels through the pharynx and trachea to the bronchi. In the lungs, air enters the alveoli where oxygen is transferred into the bloodstream.

Air enters through your lungs. It travels through the pharynx and trachea to the bronchi. In the mouth, air enters the alveoli where oxygen is transferred into the bloodstream.

Air enters through your nose and mouth. It travels through the alveoli. In the lungs, air enters the pharynx and trachea to the bronchi where oxygen is transferred into the bloodstream.

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.