Question 19 of 25 The atomic number of the element radium is 88. How many neutrons does radium-226 have? A. 98
B. 138
C. 88
D. 116
E. 226
please i need this

B. 138

Explanation:

Based on isotope notation:

For the atom A, the mass number, X, is the sum of neutrons and protons and

n is the number of protons = Atomic number.

The number of protons depends of the nature of the atom. For example, Carbon has 12 protons, hydrogen 1 and Radium has 88 protons.

The radium-226 means the mass number is 226. Thus, number of neutrons are:

Mass number - Atomic number

226 - 88 = 138

Right answer is:

B. 138

Mass is the amount of matter in an object.  weight is the measurement of the pull of gravity on an object.  say for example, you travel to the moon which has a different gravitational field compared to the gravitational field of earth. (gravitational fields: earth = 1, moon = 0.165)  now when you are on the moon, the pull of gravity on you is different than on the earth. and as weight is the measurement of the pull of gravity on an object, that means yes, your weight can and will change on the moon.  however, on the moon, on earth or even on jupiter, the amount of mass inside of you remains the same. meaning your physical mass remains constant.  in conclusion it is possible for your weight to change as your mass remains constant. 

The answer should be vaporization