Which of the following best describes an atomic number? An element's identity is defined by its atomic number; this means it represents the number of Question 19 options: A) neutrons in its nucleus. B) protons in its nucleus. C) protons plus neutrons in its nucleus. D) electrons in the element.

B

Explanation:

It's definetely not C and D, and A doesn't sound too reasonable too

in the given question, the partial pressure is calculated by using the ideal gas equation, that is, pv = nrt

here, p is pressure, v is volume = 25 l, n is number of moles = 0.0104 moles, r is gas constant = -0.0821 l.atm / mol.k

t is temperature = 273 k

p = nrt / v

p = (0.0104 mol × 0.0821 l.atm / mol.k × 273 k) / 25 l

= 0.0093 atm