Property by protons, effect
Interact with other elements depend on the electrons. Property depends on
protons.
Isotope is an atom that has a different number of neutrons.
- Irregular number of neutrons.
Carbon 12 means it has 6 protons and 6 neutrons. Carbon 14 has 2 more
neutrons. Carbon dating is when you find the ratio of carbon 12 and carbon 14
Half life is when the amount of time when carbon 14 turns carbon 12.
Ionic bonds:
Covalent bonds: When two elements bonds (same)
Hydrogen bonds: Hydrogen ions can bond (one way). H+ doesn’t have any
electrons, so they can bond.
Vander waals bonding: for example, geckos can walk on anything. Geckos have
filaments out of their palms. Forces pushed closer together and it’s a very weak
force.
H+ doesn’t have any electrons.
Draw nitrogen, N-, N-^2, N-^3, isotope of nitron (atomic mass number of 16).
Some of the properties change when it becomes an ion. Though, it will still
be reactive and a gas. 90% of the properties of atoms are decided on the number
of protons. The number of electrons changing would affect how the element
reacts/interacts with other elements. Ions still maintain the properties of the
atoms, but it’ll affect the way the atoms interact/react with other atoms. N, Nand N+ would act the same way, but they’re going to behave differently.
Isotope is when neutrons (neutrons are just mass). The changes of the
neutrons won’t affect the element’s act or behavior. Isotopes of different
chemicals have different amounts of radioactivity. Having more neutrons are less
stable atoms. Isotope means the irregular number of neutrons. 90% of atoms
have the same number of neutrons to protons. Bigger atoms, adding in neutrons,
they start falling apart and that’s radioactivity. The rate that they fall apart is
consistent. The most accurate clock ever made was based on radioactive called
the atomic clock.
We have carbon-14 and carbon-12 in our bodies. When we’re talking
about carbon-12, it means we have 6 protons and 6 neutrons, and their atomic
mass is 12. The difference of carbon-14 and carbon-12 is that carbon-14 has 2
more neutrons. Carbon-14 is more common in life. There’s a ratio of carbon-14
to carbon-12. Carbon-14 is higher than carbon-12 but when the animal dies; it
stops making carbon-14, then the ratio of carbon-14 to carbon-12 changes. It
almost comes back to being only carbon-12. Its by measuring this ratio and
knowing how much carbon-14 you started with and then we can then date lives
from many years ago. They work out the ratio and they get something called the
half-life. The half-life is the amount of time it takes for half of the sample to go
from 14 to 12. Every carbon-14 spits out 2 neutrons and becomes carbon-12 and
it does that in a regular periodic time. We can carbon-date any living things. For
example, it started with 200 grams body and we worked out that it should have a
50 g of carbon-14. Now there’s 25 grams. Therefore, it has only 1 half-life. 1 halflife is usually a thousand years, so we can conclude that the animal died a
thousand years. We’re interested in isotopes because of dating. We cannot
separate life from the environment. Isomer is related to bonds. Ionic bonds won’t
happen if carbon is going to share with carbon because they’re equal and they’re
going to get very competitive.
Covalent bonds share electrons in a region that they can overlap. It's a
very strong bond.
Ionic bond is when one gives electron to another. The result is we have
ions and it changes the way the atom interacts with other atoms.
Hydrogen bond can bond in a covalent or an ionic way. Hydrogen ion can
bond in one way. H+ is a proton and it doesn’t have any electrons orbiting/no
barrier. Since it doesn’t have electrons, it can be attracted to other atoms without
being pushed away. Hydrogen is a weak bond. It’s a positive ion being attracted
to the negative parts of another atom. Van der waals bond is the weakest one
that we know. It’s the reason that geckos can walk on walls. Geckos’ feet/palm
has a bumpy surface and they have tiny projections/filaments/looks like a hair.
As the gecko’s foot gets closer to the glass, there’s a push back. His tiny
projection gets pushed back first, the gravity of the push from the gecko is more,
so the projection penetrates through the electron clouds. Once the projection
gets through, the push goes to the other way where it pushes the projection
inside, which is pushed away from the electrons and it’s attracted to the protons
inside the glass atoms. Being repelled a little, getting through the electrons, then
being attracted to the protons. Van der waals forces is the force that makes the
atoms get very close, but it’s very weak.
Isotope:
Isotopes are variants of a particular chemical element such that, while all
isotopes of a given element share the same number of protons in each atom,
they differ in neutron numbers.
Carbon Dating:
Radiocarbon dating (or simply carbon dating) is a radiometric
dating technique that uses the decay of carbon-14 (14C) to estimate the age
of organic materials. The Earth's atmosphere contains various isotopes
of carbon, roughly in constant proportions. These include the main stable
isotope (12C) and an unstable isotope (14C). Through photosynthesis, plants
absorb both forms from carbon dioxide in the atmosphere. When an organism
dies, it contains the standard ratio of 14C to 12C, but as the 14C decays with
no possibility of replenishment, the proportion of carbon 14 decreases at a
known constant rate. The time taken for it to reduce by half is known as
the half-life of 14C. The measurement of the remaining proportion of 14
C in organic matter thus gives an estimate of its age (a raw radiocarbon age).
Covalent Bond:
A covalent bond is the chemical bond that involves the sharing of electron
pairs between atoms. The stable balance of attractive and repulsive forces
between atoms when they share electrons is known as covalent bonding.
Test:
First paragraph – CHON (structure, atomic number, list properties, 100 words,
identify CHON)
Second paragraph – Bonds (4 types, strongest to weakest, describe very roughly
what happens)
Arlindo’s Notes
Atoms – basic building block The number of protons decides the properties of
atoms. Change in electrons decides what it reacts with. Isotope is the change in
the number of neutrons. (irregular number) The more neutrons an atom has, the
more unstable it gets. We have 2 types of carbon: carbon 12 and carbon 14. Half
life is the ratio in which carbon 14 level decreases and carbon 12 increases, We
are mostly interested in isotopes because of radiometric dating. Isomers –
Chemical bonds Covalent bonds – share electrons (strongest bonds) Ionic bonds
– give electrons Hydrogen bond – hydrogen ion bonds (only proton) with a
oxygen atom (that has negative charge) It is a weak bond. Vander Waals bond –
there are microscopic filaments projecting from the gecko’s feet