Atomic Mass, Atomic Number and Isotope

In a correctly written symbol, what would be located in the "A" position?

• Mass number

• Number of neutrons

• Number of electrons

• Atomic number

In a correctly written symbol, what would be located in the "Z" position?

• Mass number

• Element's symbol

• Number of electrons

• Atomic number

How many protons does this isotope of titanium have?

• 22

• 70

• 48

• 26

Tags

NGSS.MS-PS1-1

True or False: Neutrons have a negative charge.

• True

• False

The average mass of all the isotopes of an element is known as?

• Atomic Mass

• Period

• Group

• Chemical Symbol

Given an atom with 17 protons and 20 neutrons, determine its atomic number and mass number.

• Atomic number 17, mass number 37

• Atomic number 20, mass number 37

• Atomic number 17, mass number 20

• Atomic number 37, mass number 17

Answer explanation

The atomic number is determined by the number of protons, which is 17. The mass number is the sum of protons and neutrons: 17 protons + 20 neutrons = 37. Thus, the correct choice is atomic number 17, mass number 37.

Tags

DOK Level 3: Strategic Thinking

When atoms of the same element have different atomic masses, they have different numbers of?

• protons

• neutrons

• electrons

• photons

Tags

NGSS.MS-PS1-1

If an atom has an atomic number of 7 and a mass number of 15, how many neutrons does it have?

• 7

• 8

• 15

• 22

Answer explanation

To find the number of neutrons, subtract the atomic number from the mass number. Here, mass number (15) - atomic number (7) = 8 neutrons. Therefore, the correct answer is 8.

Tags

DOK Level 3: Strategic Thinking

An isotope of an element has 47 protons and 61 neutrons. What is the mass number of this isotope?

• 61

• 108

• 47

• 108

Answer explanation

The mass number of an isotope is the sum of its protons and neutrons. Here, there are 47 protons and 61 neutrons. Therefore, the mass number is 47 + 61 = 108, making the correct answer 108.

Tags

DOK Level 3: Strategic Thinking

For Cl 37, what does the 37 represent?

• Number of Protons

• Number of Neutrons

• Number of Electrons

• Atomic Mass Number