Chemistry & Chemical Safety

Question 1

Chemistry is :

Answer 1

Science that deals with
composition
structures
& properties
of matter & how matter changes under different conditions.

Question 2

•substance that occupies space & has mass
•has physical and chemical properties •exists as solid, liquid or gas.

Answer 2

Matter

Question 3

Matter has physical properties that we can touch, taste, smell.

True or False

Answer 3

TRUE

Question 4

Light and electricity are :

Answer 4

Energy

Question 5

What is true about energy and matter?

Answer 5

Energy is not matter. Everything known to exist in the universe is made of either energy or matter. No exceptions to this rule.

Question 6

What is an element?

Answer 6

•Simplest form of chemical matter

•contains one type of atom.

•Can not be broken down to a simpler substance without loss of identity.

Question 7

How many elements are there? How many occur naturally on earth?

Answer 7

118
98

Question 8

DID YOU KNOW:

Answer 8

All matter in the known universe is made up of elements that have their own distinct physical & chemical properties?
EACH ELEMENT IS IDENTIFIED BY A LETTER STMBOL. (Ex: O = oxygen, C= carbon)

Question 9

What is an Atom?

Answer 9

Basic unit of matter with a nucleus at the center surrounded by negatively charged electrons that move around the nucleus in orbits.

Question 10

These subatomic particles have a positive charge and the amount of them determine the element:

Answer 10

Protons

Question 11

Subatomic particles with NO charge?

Answer 11

Neutron

Question 12

A chemical combination of two or more atoms in definite (fixed) proportions. (Ex: water is made from hydrogen atoms & oxygen atoms)

Answer 12

Molecule

Question 13

What is an elemental molecule?

Answer 13

A molecule containing two or more atoms of the same element

Question 14

What is a compound molecule ?

Answer 14

Chemical combinations of two or more atoms of different elements in definite (fixed) proportions.