Summary
Summary Elements and Chemical Reactions
- Course
- Institution
Book Summary containing brief notes on atoms, compounds, molecules, chemical reactions, biochemical compounds
[Show more]
Seller
Follow
imogenlaw
Content preview
Elements CompoundsA compound is formed when two or more different elements
combine in a fixed ratio by mass.
The composition of a compound is always the same.
Atoms
Biochemical Compounds
Atom = the smallest unit of matter that retains all of
the chemical properties of an element.
Composed of two regions: the nucleus (which is in the Biochemical Compounds = The compounds found in living
centre of the atom and contains protons and neutrons), things.
and the outermost region (holds its electrons in orbit
around the nucleus). Why is carbon so basic to life? Carbon’s ability to form
stable bonds with many elements, including itself. This
The 4 elements common to all living organisms are: property allows carbon to form a huge variety of very large
oxygen (O), carbon (C), hydrogen (H), + nitrogen (N).
and complex molecules.
Molecules Polymers = Very large molecules, built of repeating units of
smaller compounds called monomers.
A molecule is formed when two or more atoms join All biochemical compounds contain the elements carbon,
together.
hydrogen, and oxygen. Some contain only these elements;
Chemical bond = a force that holds together the atoms
of molecules. Bonds in molecules involve atoms sharing others contain additional elements as well.
electrons. The vast number of biochemical compounds can be grouped
into four major classes: carbohydrates, lipids, proteins, and
nucleic acids.
Chemical Reactions
Ionizations
Reactions occur when atoms combine or separate from other atoms.
When some atoms dissolve in water they become charged particles called ions, either positively
or negatively charged. Ions may have one, two or sometimes three charges.
Positive Ions = e.g H+ Hydrogen Negative Ions = e.g. OH- Hydroxyl
Positive and negative ions attract one another to hold compounds together. They conduct
electricity when dissolved in water. Substances that ionize in this way are known as electrolytes.
Organic and Inorganic Compounds
The molecules in an animal’s body fall into two groups: inorganic compounds and organic
compounds.
Inorganic compounds: do not contain carbon. E.g. water, sodium chloride, potassium hydroxide.
Water is the most abundant, making up 60% of the volume of cells and 90% of body fluids. Other
compounds help keep the pH balance and concentration of the blood and other body fluids stable
Organic compounds e.g. carbohydrates, proteins and fats/lipids. All contain carbon atoms and
they tend to be larger and more complex molecules, largely because each carbon atom can link
with four other atoms. Can consist of from one to thousands of carbon atoms joined to form
chains, branched chains and rings. All organic compounds also contain hydrogen and may also
contain other elements.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller imogenlaw. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $4.52. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
53249 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now