2.1 Atoms, Ions, Compounds

Question 1

Why is the charge on an atom neutral?

Answer 1

The proton number (+) and electron number (-) are the same

Question 2

What is the mass number (A)

Answer 2

The large number - neutron + proton

Question 3

What is the atomic number (Z)?

Answer 3

The smaller number - the proton number in the nucleus

Question 4

How do you work out the number of neutrons in the nucleus?

Answer 4

The mass number (A) - The atomic number (Z)

Question 5

What is an isotope?

Answer 5

Atoms of the same element with a different number of neutrons

Question 6

In an isotope, what happens to the atomic number and the mass number

Answer 6

The atomic number (protons) stays the same, the mass number (protons + neutrons) change

Question 7

Why don’t chemical reactions change with different isotopes of the same element?

Answer 7

Because the chemical reactions depend on the electron number on the outer shell

Question 8

What do higher mass isotopes have?

Answer 8

Higher MP’s and BP’s, and densitys

Question 9

What is an ion?

Answer 9

A charged atom- it has lost or gained electrons

Question 10

What are the name for:
• A positive ion (lost electrons)
• A negative ion (gained electrons)

Answer 10

• Positive Ion - Cation

* Negative Ion- Anion