Molecules of Life Week 2 Flashcards
Which of these factors influence the chemical behavior of atoms? Choose all that apply.
Number and arrangements of neutrons.
Number and arrangements of electrons.
The size of the nucleus
The number of protons
Number and arrangements of electrons.
Which of the following about hydrogen is True?
Hydrogen can form only polar covalent bonds.
Hydrogen has no neutron
Hydrogen is an anion when carrying a charge.
Hydrogen has two elements
Hydrogen has no neutron
Which of the following statements about electrons is NOT true?
Electrons determine the chemical behavior of atoms.
Electrons are most likely to be found in orbitals.
Electrons may move from one energy level to another.
Electrons are most likely to be found in shells.
Electrons are most likely to be found in shells.
Water molecules cause ionic or polar substances to dissociate in water by ______________.
acting as an excellent temperature buffer
breaking and reforming hydrogen bonds
forming spheres of hydration around the ions
forming strong hydrogen bonds between the water molecules
forming spheres of hydration around the ions
Which of the following statements about the lower density of ice compared to liquid water is true?
It results in evaporative cooling when animals sweat.
It allows aquatic organisms to survive during winters.
It stabilizes the temperature of the environment.
It prevents any part of a lake from freezing.
It allows aquatic organisms to survive during winters.
Which of these chemical bonds is the strongest?
Ionic bond
Covalent bond
Hydrogen bond
Van dar waals forces
Covalent bond
Water molecules attract one another through __________.
Van dar Waals forces
Ionic bonds
Hydrogen bonds
Covalent bonds
hydrogen bonds
The total number of protons in the nucleus of an atom is known as its _________________.
Proton number
Neutron number
Mass number
Atomic number
Atomic number
A newly discovered element, Az, exists in only one form naturally or artificially. If it carries no charge, and has 118 electrons and 118 protons. What will be its neutron number?
118
236
Cannot be determined
Zero
118
When atoms gain electrons in chemical reactions they are described as having been _______________.
Gained
Reduced
Excited
Oxidized
reduced
Which of these bonds are formed due to the transfer of electrons?
hydrogen bonds
covalent bonds
ionic bonds
Van dar Waals forces
ionic bonds
Which of the following statements correctly identifies and describes the type of bond found between hydrogen and oxygen atoms in water molecules?
Non-Polar covalent bonds because hydrogen is more electronegative than oxygen.
Polar covalent bonds because oxygen is more electronegative than hydrogen.
Non-Polar covalent bonds because oxygen is more electronegative than hydrogen.
Polar covalent bonds because hydrogen is more electronegative than oxygen.
Polar covalent bonds because oxygen is more electronegative than hydrogen.
An isotope of calcium has a mass number of 42. How many neutrons does it have?
19
21
22
20
22
Water molecules cause ionic or polar substances to dissociate in water by ______________.
forming spheres of hydration around the ions
forming strong hydrogen bonds between the water molecules
acting as an excellent temperature buffer
breaking and reforming hydrogen bonds
forming spheres of hydration around the ions
Isotopes with unstable nuclei (plural for nucleus) are ______________.
Ionic isotopes
Nuclear isotopes
Radioisotopes
Atomic isotopes
Radioisotopes
The concept that electrons have discrete energy levels was proposed by _______________.
Einstein
Rutherford
Bohr
Pasteur
Bohr
Which of the following statements of the three isotopes, 39K, 40K, and 41K, is False?
Potassium-39, 40 and 41 have the same number of electrons.
Potassium-39, 40 and 41 have the same atomic number.
Potassium-39, 40 and 41 have the same neutron number.
Potassium-39, 40 and 41 have the same number of shells.
Potassium-39, 40 and 41 have the same neutron number
What is the net electrical charge of water?
Positive 1
Zero
Negative 2
Negative 1
Zero
The end products of the dissociation of water molecules is/are ________________
hydrogen ions
hydrogen and hydroxide ions
liquid water and solid water
liquid water and water vapor
hydrogen and hydroxide ions
If an atom with 3 energy shells around the nucleus, where will the electrons with the highest potential energy be found.
Electrons at the K-level
Electrons at the L-level
Cannot be determined
Electrons in the M-level
Electrons in the M-level
The energy used in redox reactions in living organisms are stored in __________________.
electrons
protons
both protons and neutrons
neutrons
electrons
The space around the nucleus of an atom where it is most likely an electron can be found is the ______________.
L - shell
M - shell
K - shell
Orbital
Orbital
Insects are able to walk on the surface of water due to which property of water?
Adhesiveness
Low ice density
High specific heat capacity
Cohesiveness
Cohesiveness
Non-polar covalent bond results when ________________.
one atom is heavier than the other.
one atom is more electronegative than the other.
all atoms in the bond have the same electronegativity.
all atoms fill their outermost shell.
one atom is more electronegative than the other.
Which of these bonds is/are formed from the attraction between opposite charges?
non-polar covalent bonds
ionic and non-polar covalent bonds
ionic bonds
polar covalent bonds
ionic bonds
What type of chemical bond stabilizes crystals of table salt?
Van der Waals forces
Hydrogen bonds
Ionic bonds
Covalent bonds
Ionic bonds
