Atoms & Isotopes

What is the atomic number of Neon, Ne?

• 10
• 20.1798
• 10.1798
• 7

Tags

NGSS.MS-PS1-1

A neutral atom of the isotope ²⁶₁₂Mg would consist of

• 12 protons, 26 neutrons, 26 electrons
• 26 protons, 12 neutrons, 26 electrons
• 26 protons, 14 neutrons, 14 electrons
• 12 protons, 14 neutrons, 12 electrons

Tags

NGSS.MS-PS1-1

Which of the following statements is correct?

• protons have a mass of 1 amu

• The mass of the proton, neutron and electron is the same

• In a neutral atom the number of protons equals the number of neutrons.

• Isotopes of an element have the same number of protons but a different number ofelectrons.

An atom is electrically neutral when

• protons and neutrons are the same
• protons and electrons are the same
• neutrons and electrons are the same
• neutrons balance the protons and electrons

Isotopes of the same element have the same number of 

• protons
• neutrons
• electrons
• not enough information

Iron-60 (atomic number 26) is an isotope that is often used to study meteorites.  How many neutrons does iron-60 have?

• 26
• 60
• 34
• 86

Tags

NGSS.HS-PS1-8

Four isotopes of lead include lead-204, lead-206, lead-207, and lead-208.  The average atomic mass of lead is 207.2.  Which isotope of lead is likely to be the most abundant.

• 204
• 206
• 207
• 208

Tags

NGSS.MS-PS1-1

Which of the following particle pairs has approximately the same mass?

• protons and neutrons
• protons and electrons
• neutrons and electrons
• protons, neutrons and electrons

The element, antimony (Sb) has two major isotopes of similar abundances, both around 50%.  The atomic mass of antimony is reported on the periodic table as 121.76.  Choose the most likely set of mass numbers for these two antimony isotopes.

• Antimony-121 and Antimony-123
• Antimony-120 and Antimony-127
• Antimony-123 and Antimony 122
• Antimony-121 and Antimony-118

Tags

NGSS.MS-PS1-1

A carbon isotope consists of 6 protons, 6 electrons and 8 neutrons.  What is the mass number for this isotope?

• 12
• 14
• 6
• 8

Tags

NGSS.MS-PS1-1