- An isotope can be defined as...
- Radioactivity can be defined as...
- A compound can be defined as...
- A chemical bond can be defined as...
- Most atoms form bonds using only electrons in the...
- An electron in the outermost energy level is known as a...
- The two main types of chemical bonds are...
- An ionic bond is a bond that forms when...
- Ionic bonds occur between which two types of elements?
- Covalent bonds occur between which two types of elements?
- An covalent bond is a bond that forms when...
- One example of an ionic compound is...
- One example of a covalent compound is...
- Ionic or Covalent: a) H2 b) HCl c) NH4 d) CO2 e) Na2O f) NO3
- Some important uses of radioactive isotopes include:
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An isotope can be defined as...
an atom of the same element that has the same atomic number but has a
different atomic mass.
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Radioactivity can be defined as...
spontaneous disintegration of the nucleus of certain atoms in which it gives
of particles and energy in order to become more stable.
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A compound can be defined as...
two or more elements that are chemically combined. They can be broken down
into simpler substances.
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A chemical bond can be defined as...
an interaction that holds two atoms together in which electrons are shared,
gained, or lost.
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Most atoms form bonds using only electrons in the...
outermost energy level.
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An electron in the outermost energy level is known as a...
valence electron.
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The two main types of chemical bonds are...
ionic and covalent.
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An ionic bond is a bond that forms when...
A bond that forms when electrons are transferred from one atom to another
atom.
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Ionic bonds occur between which two types of elements?
A metal and a nonmetal
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Covalent bonds occur between which two types of elements?
Two nonmetals
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An covalent bond is a bond that forms when...
atoms share one or more pairs of electrons.
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One example of an ionic compound is...
NaCl because Na loses an electron to Cl.
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One example of a covalent compound is...
H2O because H and O share electrons in which H will now have 2 electrons in
its 1st energy level (which is the maximum number) and O will now have 8
electrons in its 2nd energy level (which is the maximum number) so they're
both happy because of the sharing of electrons! :)
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Ionic or Covalent: a) H2 b) HCl c) NH4 d) CO2 e) Na2O f) NO3
a) H2: Covalent because e-'s are shared and H & H are both nonmetals.
b) HCl: Ionic because Cl takes H's e- and H is considered a metal
(in this case) and Cl is a nonmetal.
c) NH4: Covalent because N and H share e-'s and they are both nonmetals.
d) CO2: Covalent because C and O share e-'s and they are both nonmetals.
e) Na2O: Ionic because O takes Na's e- and Na is a metal and O is a nonmetal.
f) NO3: Covalent because N and O share e-'s and they are both nonmetals.
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Some important uses of radioactive isotopes include:
Radioactive Dating (for determining the age of fossils).
Radioactive Tracers (for following the path of molecules throughout an
organism).
Radioactive Tracers are also used to find weak spots in materials and leaks
in pipes. A Geiger counter is often used to detect the tracer.
Smoke Detectors (might use a small amount of radioactive material).
Some space probes have been powered by radioactive materials. The energy
given off as nuclei decay is converted into electrical energy for the probe.
Radioactive materials can also treat illnesses like cancer.
Many food and healthcare products are sterilized using radiation.
