What do these isotopes of carbon all have in common?

• neutrons & mass number
• atomic number and neutrons
• atomic number and electrons
• protons, atomic number, and mass number

How many neutrons does the isotope of lithium have?

• 8
• 3
• 4
• 5

How many protons does this isotope of titanium have?

• 48
• 22
• 26
• 70

What quantities vary between isotopes of an element?

• protons, electrons, and atomic mass
• protons, electrons, and atomic number
• neutrons and electrons
• neutrons and atomic mass

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

Ions are: 

• atoms with a positive or negative charge
• atoms with no charge
• atoms with ONLY a positive charge
• atoms with ONLY a negative charge

What is the name of the pictured isotope?

• Carbon-12
• Carbon-13
• Carbon-14
• Carbon-15

What are isotopes?

• Atoms of the same elements which have the same number of protons but different number of neutrons.

• Atoms of the same elements which have the same number of electron but different number of neutrons.

• Atoms of the same elements which have the same proton number but different number of neutrons.

• Atoms of the same elements which have the same number of protons but different nucleon numbers.

Here are three isotopes of an element.

Bromine-71

Bromine-77

Bromine-82

The numbers 71, 77, 82 are the ____.

• electron number

• mass number

• neutron number

• atomic number

Fe₂O₃ + 3H₂ → 2Fe + 3H₂O

How many moles of iron can be made from  6 moles H₂? 

• 4 moles Fe

• 6 moles Fe

• 9 moles Fe

• 2 moles Fe