Chapter 2 - Atoms and Elements

Question 1

What are subatomic partricles?

Answer 1

Proton - +1
Neutron - 0
Electron - -1
- If a proton had the mass of a baseball, an
electron would have the mass of a rice grain

Question 2

How much empty space do atoms have?

Answer 2

Atoms have so much empty space that 50 trillion neutrinos pass through a human being every second

Question 3

What does the atomic number Z (bottom left of an element) stand for?

Answer 3

• The number of protons in the nucleus
• Defines the element

Question 4

What does the mass number A (top left of an element stand for?

Answer 4

• Neutrons and protons (added together)
• differ among isotopes

Question 5

What are isotopes?

Answer 5

For any element, all isotopes have:
- The same number of protons
- The same chemical reactivity
- Different numbers of neutrons

Question 6

How many isotopes are radioisotopes?

Answer 6

> 90% of isotopes are radioisotopes, and every element has at least one radioisotope

Question 7

What 2 pieces of information does the atomic mass provide?

Answer 7

• The mass in grams of 1 mile of an atom
• The average mass of an atom

Question 8

Given the mass of a compound what can we find?

Answer 8

We can find the number of atoms in the sample, and vice versa