- Solutions – the mixture of two or more substances
- Solute – that which dissolves in a solvent (like salt dissolves in water)
- Solvent – that which dissolves the solute (like water, the universal solvent).
- Compounds – chemical combinations of two or more types of elements
- Chemical Bonds form through either
- Negative-poitive attraction between atoms
- Satisfying of energy levels/valence shells
- Shells typically exist as 2, 8,18, 32
- Types of Bonds:
- Ionic Bonds – electrons are transferred from one atom to another.
- Covalent Bonds – valence electrons are shared between two or more atoms (strongest of bonds)
- Hydrogen Bonds – a weak bond between a hydrogen and another electronegative atom.
Cornell Note-Taking System Instructions:
- Record: During the lecture, use the note-taking column to record the lecture using telegraphic sentences.
- Questions: As soon after class as possible, formulate questions based onthe notes in the right-hand column. Writing questions helps to clarifymeanings, reveal relationships, establish continuity, and strengthenmemory. Also, the writing of questions sets up a perfect stage for exam-studying later.
- Recite: Cover the note-taking column with a sheet of paper. Then, looking at the questions or cue-words in the question and cue column only, say aloud, in your own words, the answers to the questions, facts, or ideas indicated by the cue-words.
- Reflect: Reflect on the material by asking yourself questions, for example: “What’s the significance of these facts? What principle are they based on? How can I apply them? How do they fit in with what I already know? What’s beyond them?
- Review: Spend at least ten minutes every week reviewing all your previous notes. If you do, you’ll retain a great deal for current use, as well as, for the exam.
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Welcome to the chemistry unit, today we are going to discuss chemical bonds and compounds.
We will begin by discussing what solutions are. In the picture, you can see the addition of a solute to a solvent….the universal solvent know as water. the solute, in this case, is salt and together the salt and water create a solution, a saltwater solution that is.
A compound is what is made when two or more elements combine chemically. So let’s go back to our universal solvent, water. It is composed of two elements, hydrogen, and oxygen that which when they are by themselves they are both gases, one being flammable and the other explosive. Yet when two atoms of hydrogen chemically combine they create a liquid that life cannot exist without…..H2O.
So how does this chemistry occur? Well, the bottom line is that chemistry happens because of electrons. Specifically, those electrons arranged in the outermost shells. So there can be chemical bonds that form between atoms due to positive and negative charges (opposites attracting). Or chemical bonds can form between atoms when they satisfy valence shells (which are the outermost shells of electrons. So electrons tend to spin around the nucleus in different orbits/energy levels. These shells typically exist with the first level holding 2, then 8 after that.
So chemistry happens through electron shells being satisfied. This can happen through bonding. There are 3 main types of chemical bonds. ionic bonds are when electrons are transferred from one atom to another. The formation of Sodium Chloride is a great example of ionic bonding. Na donates an electron to Cl and both have their outermost shells satisfied. Covalent bonds share their outermost electrons. The formation of water is through covalent bonding. Two hydrogen elements share their outermost electrons with one oxygen and form H2O. Covalent bonds an extremely strong, as opposed to hydrogen bonds, which are weak bonds formed through hydrogens slight positive charge being attracted and forming weak temporary bonds to negatively charged molecules. Such as that which forms when water molecules stick to each other.
To summarize, solutions form when a solute dissolves in a solvent. Compounds are the result of two or more atoms combining chemically. Ionic bonds form when atoms transfer electrons, covalent bonds form between atoms that share outermost valence electrons and hydrogen bonds (which are weak bonds) form when hydrogens are attracted to negatively charged atoms.
Thank you for reviewing chemical bonds and compounds with us today. Now go out and be your best self today and happy nursing!