chem gr 11 review Flashcards
How do isotopes of the same element differ from each other?
An isotope differs in abundance, atomic mass and neutrons. It has the same protons and atomic number.
What is the purpose of using radioactive tracers in medical imaging?
Injected into the body of
patients to detect abnormalities such as cancer
Radioisotopes can cause..
Cancer, but can also be used for medical purposes.
Unstable isotopes are called..
radioisotopes
What are isotopes?
Atoms of the same element with the same atomic
number but different atomic mass are called isotopes.
Electronegativity - elements on the left side vs the right side
Elements on the left side of the periodic table have little tendency to accept
electrons, elements on the right side have a high tendency to accept electrons.
Explain how ionic bonds are formed. Provide an example of an ionic bond between two elements.
Sodium and chlorine, ionic bonds are formed by cations and anions.
ionic bonding occurs…
It occurs between non metals and metals, metals lose electrons to non metals (attractions between ions)
What is half life
the time taken for half the sample of a
radioactive isotope to decay into another element
What is covalent bonding
sharing e-
between atoms/two non metals to create molecules
with a stable electronic configuration.
Non metals are cations or anions? Accepting electrons or donating?
Non metals accept electrons and are anions
Metals are cations or anions? Accepting electrons or donating?
cations, they donate
What are valence electrons
The electrons in the
outermost shell of
an atom. Determines the
chemical and
physical properties
of an element
Elements that have a _______ in
their electronegativity are most
likely to form _________
Large difference, ionic bonds
non-metals that are close together on the
periodic table, and have a small
difference in their Electronegativity are likely to form a
covalent bond
Electronegativity increases as….
you move to the right across the
periodic table
Electronegativity decreases as..
You move down the columns or family
non polar covalent bond is
e- in the bond are shared equally
between the atoms
polar covalent bond is
e- are NOT shared equally
What is electronegativity
The desire of an element
to gain electron(s) and to measure the ability of an atom when attracting electrons.
Polar covalent bond is caused by
a difference in electronegativity
For a molecule to be polar, it must
contain:
polar bonds, asymmetric axis offering a partial
+ve and a partial –ve end.