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what does atomic number describe?

a. mass

b. number of neutrons

c. number of protons

d. atomic weight
what is the number of protons plus the number of neutrons in the nucleus of an atom equivalent to?

a. atomic charge

b. mass number

c. atomic number
d. average atomic mass

1 is c 2 is b

Explanation:

because atomic number is the number of protons in a nucleus

2..because the number of protons plus number of neutrons is equal to mass number.

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"

a electronegativity decreases beacuse the size of nucleus is bigger.