What is the name of the smallest unit that still has the properties of an element?
Atom
Which subatomic particle has a positive charge?
Proton
What does the atomic number tell you about an element?
The number of protons
How many oxygen atoms are in CO₂?
2
Which two particles are found in the center of an atom?
Protons and neutrons
Which two particles are found in the nucleus?
Protons and neutrons
Which subatomic particle has a charge of N0?
Neutron
A pure element has an atomic number of 7. How many electrons does it have?
7
How many total atoms are in H₂S?
2 H + 1 S = 3
An atom has an atomic number of 8. How many protons does it have?
8 protons
Which subatomic particle moves around outside the nucleus?
Electron
Which subatomic particle has a (-) charge?
Electron
A neutral atom has 13 protons. How many electrons does it have?
13
How many total atoms are in C₂H₄?
2 C + 4 H = 6
How many total atoms are in 2H₂O?
2 × (2 H + 1 O) = 6
Which part of an atom contains most of its mass?
The nucleus
A particle is located in the nucleus and has no charge. What particle is it?
Neutron
An element has an atomic mass of 27 and an atomic number of 13. How many neutrons does it have?
27 − 13 = 14
How many total atoms are in Al₂O₃?
2 Al + 3 O = 5
How many total atoms are in Ca(OH)₂?
1 Ca + 2 O + 2 H = 5
An atom has 12 protons, 12 neutrons, and 12 electrons. How many subatomic particles are in the atom altogether?
36
A student says, "Electrons are found in the nucleus because they are part of the atom." Explain why this is incorrect.
Electrons are found outside the nucleus in the electron cloud.
An element has an atomic mass of 40.099 and an atomic number of 20. How many neutrons would you expect after rounding the mass?
40 − 20 = 20
How many total atoms are in C₆H₁₂O₆?
6 C + 12 H + 6 O = 24
How many total atoms are in 3Ca(OH)₂?
Work:
Ca = 3
O = 6
H = 6
3 + 6 + 6 = 15