Question

question 14 (1 point)
(02.02 mc)
zinc has the chemical symbol zn and the atomic number 30. how many protons, neutrons, and electrons does an atom of zinc - 69 have?
a 30 protons, 39 neutrons, 39 electrons
b 39 protons, 30 neutrons, 30 electrons
c 39 protons, 30 neutrons, 39 electrons
d 30 protons, 39 neutrons, 30 electrons
question 15 (1 point)
(02.02 lc)
an atom has atomic number 5 and mass number 11. how many neutrons does the atom have?
a 5
b 6
c 10
d 11
question 16 (1 point)
(02.02 lc)
an atom has atomic number 11 and mass number 23. how many electrons does the atom have?
a 23
b 22
c 12
d 11

Explanation:

Step1: Recall atomic number concept

The atomic number is equal to the number of protons and in a neutral - atom, the number of electrons. For zinc, atomic number \(Z = 30\), so number of protons \(p=30\) and number of electrons \(e = 30\).

Step2: Calculate number of neutrons

The mass number \(A\) of zinc - 69 is 69. The formula for mass number is \(A=p + n\), where \(n\) is the number of neutrons. So \(n=A - p\). Substituting \(A = 69\) and \(p = 30\), we get \(n=69 - 30=39\). For question 14, the atom of zinc - 69 has 30 protons, 39 neutrons, and 30 electrons.

For question 15:

Step1: Recall mass - number formula

The mass number \(A\) is the sum of protons \(p\) and neutrons \(n\), \(A=p + n\). Given \(A = 11\) and \(p=5\) (since atomic number = number of protons). Then \(n=A - p\).

Step2: Calculate number of neutrons

Substitute \(A = 11\) and \(p = 5\) into the formula \(n=A - p\), we get \(n=11 - 5 = 6\).

For question 16:

Step1: Recall electron - proton relationship in neutral atom

In a neutral atom, the number of electrons \(e\) is equal to the number of protons \(p\). Given the atomic number \(Z = 11\), so the number of protons \(p = 11\), and the number of electrons \(e=11\).

Answer:

Question 14: d. 30 protons, 39 neutrons, 30 electrons
Question 15: b. 6
Question 16: d. 11