Can someone pls explain how I find the answers because my teacher didn’t explain it thoroughly.

KEY POINTS

Atomic no. = no. of protons

•No. of protons = no. of e- (For neutral )

•No. of neutron = Mass no. - atm no.(or no. of p)

Ex1- Atm no. =19

--->■ therefore no. of proton also 19

ii)no. of neutron=mass no. - atomic no.

=39 - 19

=20

iii) no. of e=no of proton (for neutral) ex He Ar H

□●■for charged species(ex Li+,cl-)

no. of e = no. of proton +/- charge

a))if charge is + then subtract that charge from proton then you will get no. of e

Ex K+

no. of e = no. of proton -1

=19-1=18

b)if charge is -ve then add that charge to no. of proton then we will get no.of e

Ex- cl-

no. of e- = no. of proton+ 1

=17+1=18

THANK YOU

kuchisake

kuchisake-onna (口裂け女, "slit mouth woman ") is a malevolent figure appearing in japanese ghost stories, possibly dating back to the edo period. she takes the form of a masked woman who approaches people and asks them if they believe she is pretty.

explanation:

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.