Chapter 1- How did Chemistry begin?

Question 1

State the Law of Conservation of Mass.

Answer 1

Mass of reactants = Mass of Products.

Matter is not created or destroyed during a chemical reaction. -Antoine Laviosier

Question 2

Who first defined an ‘element’?

Answer 2

Robert Boyle

Question 3

Define: Element

Answer 3

Simple pure substance

Substance composed of atoms with the same atomic number.

Question 4

Define: Compound

Answer 4

Combination of elements

Question 5

Define: Chemist

Answer 5

A person engaged in chemical research or experiments.

Question 6

Define: Alchemist

Answer 6

A practitioner of alchemy whose main goal is to turn base metals into gold.

Question 7

How is a compound formed?

Answer 7

Wen the atoms of two or more different elements combine.

Question 8

What did John Dalton, English chemist, 1805, propose?

Answer 8

All elements were composed of atoms that were characteristic of that element, and chemical reactions involved the rearrangement of these atoms.

Question 9

Name the major contributors to the development of the periodic table.

Answer 9

• John Newlands
• Lothar Meyer
• Dimitri Mendeleev (1869)

Question 10

How did Mendeleev organize the periodic table?

Answer 10

Arranged the elements in order of increasing atomic weight, noted the properties of elements that varied periodically with their atomic weight and let gaps in his table for undiscovered elements using period trends.