Chemical Formulae

Question 1

What do the subscript numbers in a molecular formula do?

Answer 1

When writing a molecular formula (or any chemical formula), subscript numbers, such as the 3 in CaCO3, represent the number of atoms of that element within the compound.

Question 2

What does 2CO(mini 2) mean?

Answer 2

2CO(mini 2) means two molecules of carbon dioxide, each consisting of one atom of carbon and two atoms of oxygen.

Question 3

What does the group number of group l, ll and lll tell us regarding charge?

Answer 3

Elements in groups I, II and III form positive ions with a number of charges equal to the group number.

Question 4

What does the group number of group V, Vl and Vll tell us regarding charge?

Answer 4

Elements in groups V, VI and VII form negative ions with a number of charges equal to eight minus the group number.

Question 5

How do the positions of elements in the Periodic Table influence the ions they form?

Answer 5

The position of elements determines whether they form positive or negative ions.

Question 6

What type of ions do elements in groups I, II, and III form?

Answer 6

They create positive ions with charges equal to their group number.

Question 7

What type of ions do elements in groups V, VI, and VII form?

Answer 7

They yield negative ions with charges equal to eight minus their group number.

Question 8

Which elements do you balance last?

Answer 8

Hydrogen and oxygen

Question 9

What is a monatomic ion?

Answer 9

A monatomic ion is an ion made of exactly one atom. In other words, it is an atom that has an unequal number of protons and electrons.