Chemistry

Question 0

What are 5 examples of elements?

Answer 0

Hydrogen (H2)
Oxygen (O2)
Copper (Cu)
Silver (Ag)
Carbon (C)

Question 1

What is Chemistry?

Answer 1

Chemistry is the study of matter and the changes that take place with that matter

Question 2

What is the definition of element?

Answer 2

Element - a pure substance which cannot be broken down

Question 3

What is the definition of compound?

Answer 3

Compound - 2 or more elements that are chemically combined

Question 4

What is the definition of Atomic Number?

Answer 4

Atomic Number - the number of protons in one atom of an element

Question 5

Who designed the Periodic Table and when did he design it

Answer 5

The Periodic Table was designed by Dmitri Mendleev in 1960

Question 6

What are the horizontal rows and vertical columns called?

Answer 6

Horizontal Rows - Periods

Vertical Columns - Groups

Question 7

What are the 3 main categories on the Periodic Table?

Answer 7

The three main categories are Metals, Non-Metals and Semi-Metals

Question 8

What three things does an element always have?

Answer 8

Each element has a name, symbol and atomic number

Question 9

Why do chemicals react?

Answer 9

Chemicals, whether elements or compounds, react to become more stable

Question 10

Wha happens when chemicals react?

Answer 10

Chemicals can change colour, change phase, generate heat or start a chain reaction

Question 11

What are the properties of metals?

Answer 11

Metals are usually shiny, solid at room temperature, have high melting point, malleable and ductile, usually easy to mix, good conductors of heat

Question 12

What are the properties of Non-Metals?

Answer 12

They do not conduct electricity/heat, can be solid/liquid/gas at room temperature

Question 13

What are the 2 main elements that make up the Earths crust?

Answer 13

The 2 main elements are Silicon and Oxygen

Question 14

What are the properties of Semi-Metals?

Answer 14

Look metallic, and are brittle, only conduct electricity when heated

Question 30

What are the properties of an acid?

Answer 30

Acids are sour and not slippery

Question 31

On the pH scale, where do acids fall and where is a strong acid located on this scale?

Answer 31

On the pH scale, acids fall between 0 and 7, and strong acids will be around 2 or 3

Question 32

What are the properties of a base?

Answer 32

Bases generally feel soapy and are bitter in taste

Question 33

What are bases that dissolve in water called, and what is the solution that is formed?

Answer 33

Bases that dissolve in water are called alkalis and an alkaline solution is formed

Question 34

What is an indicator?

Answer 34

An indicator is a substance that changes colour when added to a base or acid

Question 35

What colour it Litmus Paper in an acid, and what colour is it in a base?

Answer 35

Litmus Paper is red in an acid, and blue in a base

Question 36

What colour is Bromothymal Blue in an acid, and what colour is it in a base?

Answer 36

Bromothymal Blue is yellow in an acid, and blue in a base

Question 37

What is water said to be, because it is not an alkali or a acid?

Answer 37

Water is said to be neutral because it has no effect on Litmus Paper

Question 38

What will an acid + base produce?

Answer 38

An acid + a base will produce salt + water

Question 39

What is the acid that we find in our stomachs called?

Answer 39

The acid that is in our stomach is called Hydrochloric Acid

Question 40

What do we take to neutralize the excess stomach acid?

Answer 40

We take milk of magnesia or Eno to neutralize the excess stomach acid

Question 41

What happens when the harmful gases combine with the water vapor in the air?

Answer 41

When these gases combine with the water vapor in the air, they create an acid called sulphurus acid

Question 42

When sulphurus acid is released from the clouds and comes down as rain, what is it called and what damage can it cause?

Answer 42

When this is rained down we call it ‘acid rain’, and this rain can damage buildings, statues and burn leaves of plants