1. If the atomic number is 25, how many protons does it have?
2. If the atomic mass is 55 (rounded) and mass= protons + neutrons, how many neutrons does it have?
Remember the atomic number is equal to the number of protons and electrons. (in an element)
2. Well if mass is 55 what element is it (look at the period table). Now that you know the element, you know how many protons are in it, now how many electrons are left to make up the atomic mass?
hmmm. do you know what determines the atomic number?
then, protons+neutrons=55, so if you have the protons, getting the neutrons is easy ... right?
Thanks
To answer question 1, we need to understand that the atomic number of an element represents the number of protons in its nucleus. The atomic number is often denoted by the letter Z. In this case, the atomic number is 25. So, the element in question has 25 protons.
To answer question 2, we can use the atomic mass of the element and the knowledge that the atomic mass is approximately the sum of the protons and neutrons in the nucleus. Let's denote the number of neutrons as N. The atomic mass is given as 55 (rounded). Therefore, the atomic mass (55) is equal to the sum of the protons (25) plus the neutrons (N). We can solve for N by subtracting 25 from both sides of the equation:
Atomic mass = Protons + Neutrons
55 = 25 + N
Subtracting 25 from both sides:
N = 30
Therefore, the element in question has 30 neutrons.