Ch. 2 Atomic & Molecular Structure Flashcards
(18 cards)
The nucleus of a Potassium atom contains ____________.
19 protons
19 electrons
39 neurons
20 neutrons
A and D
A and D
because electrons are not found in the nucleus
What is the maximum number of electrons the can occupy the second energy level of Nitrogen?
2
4
8
18
32
8 electrons that can occupy the second energy level is 2x2^2= 8 electrons.
1st orbital =2
2nd orbital = 8
3rd orbital = 18
4th orbital = 32
An element has an atomic number of 15, Based on its electron configuration how many electrons are in the second energy level?
2
6
8
10
8 we know the second orbital has a max of 8.
Which of the following statements is true regarding isotopes?
A. Isotopes of the same element have different atomic numbers
B. Isotopes differ in their number of electrons
C. Isotopes differ in their number of neutrons
D. Isotopes have different numbers of protons
C. Isotopes differ in their number of neutrons
Which isotope of carbon is most abundant in nature?
A. Carbon-12
B. Carbon-13
C. Carbon-14
D. All three are equally abundant
A. Carbon-12
An element has two isotopes, A-10 and A-11. If A-10 is 75% abundant, what is the atomic mass of element A?
A. 10.25
B. 10.50
C. 10.75
D. 11.00
A. 10.25
(10)(0.75) + (11)(0.25) = 7.5 + 2.75 = 10.25
An element with 25 protons is an example of ___________.
Alkali Metals
Alkaline Earth Metals
Transition Metals
Halogens
Nobel Gases
Transition Metals
Magnesium and Calcium are both examples of ___________.
Alkali Metals
Alkaline Earth Metals
Transition Metals
Halogens
Nobel gases
Alkaline Earth Metals
The period number indicates the _________.
number of energy levels (shells)
number of valence electron
number of electrons in each energy level
octet rule
none of the above
number of energy levels (shells)
An element with 15 protons has _________.
5 valence electrons
15 neutrons
31 neutrons
2 atomic orbitals
15 valence electrons
5 valence electrons
Which of the following statements about the structure of an atom is true?
Electrons have a greater mass than protons.
Protons and neutrons are located in the nucleus, while electrons are found in orbitals around the nucleus.
The number of neutrons in an atom determines its atomic number.
Isotopes differ in their number of protons.
All of the above.
Protons and neutrons are located in the nucleus, while electrons are found in orbitals around the nucleus.
When a hydrogen electron transitions from n=3 to n=2, which of the following statements is true?
Energy is emitted.
Energy is absorbed.
The electron loses energy.
The electron gains energy.
A and C
A and C
Which of the following statements about ions is correct?
Anions are positively charged ions formed by the loss of electrons.
Cations are negatively charged ions formed by the gain of electrons.
A chloride ion (Cl⁻) is formed when chlorine gains one electron.
A sodium ion (Na⁺) is formed when sodium gains one electron.
An ion with a negative charge is called a cation.
A chloride ion (Cl⁻) is formed when chlorine gains one electron.
Which of the following elements is a metalloid?
Sodium (Na).
Oxygen (O).
Calcium (Ca).
Chlorine (Cl).
Silicon (Si).
Silicon (Si). ( in the zigzag line)
Which of the following statements is true?
Alkali metals are hard and have high melting points.
Nonmetals are good conductors of electricity and heat.
Noble gases are highly reactive and form many compounds.
Transition metals have high melting points and can form multiple oxidation states.
Halogens are chemically inert and do not form compounds easily.
Transition metals have high melting points and can form multiple oxidation states.
Which gap between the energy levels that when decreases moves away from the nucleus larger?
A. n=1 to n=2
B. n=4 to n=5
A. n=1 to n=2
Define some cool facts about, Non metals, Alkali Earth metals, Noble gas, and halogens
Alkali metals: highly reactive, low mp. Noble gas:stable and unreactive.
Halogens: very reactive
What does Isoelectronic mean?
two elements can have the same number of protons but different numbers of electrons due to their charge
ex. Mg- and Al
