chemistry v2 Flashcards
(31 cards)
The elements referred to as the noble gases are found in which block of the periodic table?
P-block (noble gases are group 18 elements)
define the term “electronegativity”
The ability of an atom to attract electrons, electronegativity increases due to increasing core charge.
define the term “ionisation energy”
The amount of energy required to remove an electron from an isolated atom or molecule.
which element in the periodic table has the strongest attraction between nucleus and valence electrons?
Fourine, flourine has a high core charge and small atomic radius.
explain how electronegativity is related to ionisation energy
Both ionisation energy and electronegativity relate to electrons. ionisation energy is the energy required to remove an electron from a gaseous atom or ion, while electronegativity is the ability of the nucleus of an atom to attract an electron to itself.
why do metals generally have low electronegativities, whereas non-metals have high electronegativities?
Metals have a low effective nuclear charge and, therefore, do not strongly attract the outermost electrons. Non-metals have a high effective nuclear charge and so more strongly attract outershell electrons.
what is development that meets current needs without affecting the ability of future generations to meet their own needs called?
Sustainability
Explain why helium is considered a critical element when it is the second most abundant element in the universe.
Helium is abundant in the universe but not on earth because it’s a very light gas and if it escapes after use it is lost into the atmosphere.
what determines the chemical properties of an element?
number of electrons
Different isotopes of the same element have different what?
number of neutrons
how can the periodic table of the elements be used?
To predict how atoms of different elements will combine
what type of transition results in an emmission spectrum?
Electrons transitions from higher to lower energy states produce emission epectra.
what are orbitals?
regions within a subshell in which electrons move.
what is the pauli exclusion principal?
maximum of two electrons per orbital
what is core charge?
attractive force of the nucleus on the valence electrons
what is the formula for core charge?
Core charge = (no. of protons) - (no. of inner shell electrons)
what are groups?
Elements that have the same valence electrons, therefore having very similar chemical properties.
what are periods?
Same number of shells, but elements have different properties
Going down a group, the atomic radius (blank) and going across a period the electronegativity (blank).
increases, increases
Explain the relationship between ionisation energy and reactivity of metals.
The lower the ionisation energy, the easier an electron is lost and thus reactivity is greater.
what is the name for elements in groups 3 to group 12 on the periodic table?
Transition elements ( d-block)
what are some groups on the periodic table?
group 1 = alkali metals
group 2 = alkaline earth metals
group 13 = boron family
group 14 = carbon family
group 15 = nitrogen
group 16 = chalogens
group 17 = halogens
group 18 = noble gases (unreactive)
what is circular economy
Economy in which waste and pollution is eliminated, products at the end of life are released, repaired or recycled, and the environment is not farmed.
what is green chemistry?
The design of chemical products and processes that decreases or elminates the use or creation of hazardous wastes and the impact on the environment
