CHAPTER 1

Question 1

What are all organisms made of ?

Answer 1

Matter

Question 2

What is matter?

Answer 2

Anything that takes up space and has a mass and is made of elements

Question 3

What are elements ?

Answer 3

A substance that can’t be broken down to other substances by chemical reactions

Question 4

How many elements are there?

Answer 4

92 out of those there are 20-25 % that are essential elements

Question 5

What are essential elements ?

Answer 5

One that an organism needs in order to remain healthy and reproduce

Question 6

What are the elements all organisms need?

Answer 6

Oxygen, hydrogen, nitrogen and carbon
These make up 96 percent of living matter
(Remaining are Carbon ,P,K,S)

Question 7

What are trace elements ?

Answer 7

Elements that are required by the organism in very small amounts (iron and iodine)

Question 8

What are elements composed of ?

Answer 8

Small units of matter that still retain properties of that element also known as atoms

Question 9

What are atoms composed of?

Answer 9

Smaller parts called subatomic particles

Question 10

What are the three subatomic particles?

Answer 10

Neutrons (neutral charge)
Protons (positively charged )
Electrons ( negative charged)

Question 11

Where are protons and neutrons found?

Answer 11

In the atomic nucleus

Question 12

Where are electrons found ?

Answer 12

Surround the nucleus in a cloud

Question 13

How can the number of electrons be determined?

Answer 13

By the atomic number
Since all atoms have a neutral charge the # of protons = the number of electrons

Question 14

What is a compound ?

Answer 14

A substance consisting of two or more elements combined in a fix ratio, its characteristic are different from those of its elements

Question 15

Where are an atoms electrons found?

Answer 15

Distances away from the nucleus and vary in the amount of energy the possess

Question 16

Where are electrons found?

Answer 16

They are found on electron shells which is basically shells distances away from the nucle

Question 17

Do electrons have more energy closer to the nucleus or not?

Answer 17

No electrons further away have more energy

Question 18

What describes the chemical behaviour of an atom?

Answer 18

It’s defined by the electron configuration and distribution (can find the electron configuration by the periodic table )

Question 19

How many electrons can each shell hold?

Answer 19

1= 2
2=8
3=8
Electrons fill up the lowest energy levels first

Question 20

What are valence electrons?

Answer 20

The electrons on the outermost shell (determine the chemical behaviour of an atom)

Question 21

What is the outer most shell called?

Answer 21

Valence shell

Question 22

What does valence of an atom refer to?

Answer 22

The number of unpaired electrons in its valence shell

Question 23

What determines if A atom is reactive ?

Answer 23

If the atom does not have a completed valence shell it is considered reactive
(Can combine or interact with other atoms that it comes in contact with)