Chemistry Flashcards
What is a chemical symbol?
It is a symbol given to represent a basic element
How many elements are there in all?
118
How many elements are naturally occurring?
92
What is a periodic table?
It is an organised table of all known elements. It has a numbering system
How are elements organised in the periodic table?
With the heaviest elements at the bottom and the lightest elements at the top
Elements are organised in columns according to their common chemical properties
What case letters should chemical symbols be in?
Chemical symbols start with a capital letter and if they have a second letter (for example Ca) the second letter is lower case
What are the ten most common elements in the human body?
Oxygen Carbon Hydrogen Nitrogen Calcium Phosphorus Potassium Sulfur Chlorine Sodium
All others
What is the chemical symbol for oxygen?
O
What is the chemical symbol for carbon?
C
What is the chemical symbol for hydrogen?
H
What is the chemical symbol for nitrogen?
N
What is the chemical symbol for calcium?
Ca
What is the chemical symbol for phosphorus?
P
What is the chemical symbol for potassium?
K
What is the chemical symbol for sulfur?
S
What is the chemical symbol for chlorine?
Cl
What is the chemical symbol for sodium?
Na
What percentage of the body is made up of oxygen?
65%
What percentage of the body is made up of carbon (C)?
18%
What percentage of the body is made up of hydrogen (H)?
10%
What percentage of the body is made up of nitrogen (N)?
3%
What percentage of the body is made up of calcium (Ca)?
1.5%
What percentage of the body is made of phosphorus (P)?
1.2%
What percentage of the body is made up of potassium (K)?
0.4%
What percentage of the body is made up of sulfur (S)?
0.25%
What percentage of the body is made up of chlorine (Cl)?
0.2%
What percentage of the body is made up of sodium (Na)?
0.2%
Where should the units of the values be written when producing a table?
Units should be written in the column headings instead of next to each individual value
Which element is the lightest?
Hydrogen (H)
What is the third most abundant element in the universe by mass?
Oxygen (O)
What percentage of nitrogen forms the earths atmosphere?
78%
Where can red phosphorus most commonly be found?
On matchboxes, to light matches
Which element is a component of gun powder?
Sulfur (S)
What element is essential for plant growth?
Potassium
Where is phosphorus present in the human body?
In bones and teeth
What is Phosphorus (P) essential for in the human body? (2)
Energy storage and transfer
Correct function of cells
How many natural forms are there of phosphorus (P)?
Two
White phosphorus
Red phosphorus
Describe the properties of white phosphorus (P)? (5)
Poisonous Waxy Solid Glows in the dark Flammable when exposed to air
What happens when phosphorus is exposed to air?
It is flammable
Is red phosphorus (P) toxic?
No it is non toxic
How does hydrogen (H) occur in its natural form?
As a colourless
Odourless
Gas
How much of the human body is made up of water?
70% by mass
Which element is there an abundance of in living organisms?
Oxygen
Hydrogen
What does sodium (Na) combine with to form salt?
Chlorine (Cl)
What does sodium (Na) regulate in the body?
Blood chemistry and the amount of water in our bodies
Is sodium (Na) vital to human life?
Yes without it our cells can not get the nutrients they need to survive
Describe the properties of sodium (Na)?
Soft solid
Highly reactive
Describe the properties of potassium (K) in its natural form?
Soft, silvery solid
Tarnishes rapidly in air
What is potassium (K) vital for in the human body?
It helps cells all over the body regulate what enters and leaves them so it is vital for all movement and body functions
What are the most important roles for calcium (Ca) in the human body? (4)
Building and maintaining bones/teeth
Necessary for blood clotting
Muscle contraction
Conduction of nerve impulses
Describe the properties of calcium (Ca)?
Calcium is silvery
Soft solid
Tarnishes rapidly in air
Reacts with water
What does the element calcium react to?
Water
Graphite and diamond are well known forms of which element?
Carbon (C)
In its natural form
Is carbon an important element to life?
Yes, virtually every part of our bodies is made with large amounts of carbon
Describe the properties of Graphite?
Natural form of Carbon Grey Shiny Soft Solid
Describe the properties of diamond?
Colourless
Transparent
Solid
Very hard
Describe the properties of nitrogen (N)?
Colourless
Odourless
Gas
What crucial role does nitrogen play in the human body?
It plays a crucial role in digestion of food and in growth
Describe the properties of Oxygen? (O)
Colourless
Odourless
Gas
In natural form
What role does sulfur (S) play in the human body?
It is used in small amounts in all areas of the body to protect cells from hazards such as air pollution and radiation
Historically what was sulphur used for?
It was burned to fumigate rooms after illness
What is the most common appearance of sulphur?
Yellow crystals or powder
What role does chlorine (Cl) play in the human body?
It regulates the amount of fluids in the body and helps muscles to flex and relax
Which element is chlorine (Cl) mixed with to produce stomach acid to digest food properly?
Hydrogen
This forms hydrochloric acid
Describe the properties of Chlorine?
Yellow- green
Dense gas
Choking smell
What two elements form salt?
Sodium (Na)
Chlorine (Cl)
Form Sodium Chloride (salt)
Apart from use in the human body what else can Chlorine be used in?
It can be used as a disinfectant