Chemistry regents exam practice questions
which equation represents a single replacement reaction
2Al(s) + 6HCl(aq) ----> 2AlCl3(aq) + 3H2(g)
which equation represents conservation of charge
2I- ----> I2 + 2e-
which element requires the least amount of energy to remove the most loosely held electron from a gaseous atom in the ground state
Na
what occurs during this reaction: H + H ----> H2
a bond is formed and energy is released
which emission causes the atomic number of a nuclide to decrease by 2 and its mass number to decrease by 4
an alpha particle
which statement describes the earliest model of the atom
an atom is an indivisible hard sphere
when comparing voltaic cells to electrolytic cells, oxidation occurs at the
anode in both type of cells
for a chemical system at equilibrium, the concentrations of both the reactants and the products must
be constant
which term represents the fixed proportion of elements in a compound
chemical formula
which statement describes the energy and bonding changes as two atoms of fluorine become a molecule of fluorine
energy is released as a bond is formed
which radioactive emission has the greatest penetrating power, but the least ionizing power
gamma ray
based on table n, uranium-238 and uranium-235 have different
half-lives
which term identifies a type of intermolecular force
hydrogen bonding
the mass of an electron is
less than the mass of a neutron
systems in nature tend to undergo changes toward
lower energy and greater randomness
the element in group 14, period 3, of the periodic table is classified as a
metalloid
what statement describes the reactions in an electrochemical cell
oxidation occurs at the anode, and reduction occurs at the cathode
which symbol represents a particle that has a mass approximately equal to the mass of a neutron
p
which particles are found in the nucleus of an argon atom
protons and neutrons
which terms represent two types of organic reactions
saponification and fermentation
according to the kinetic molecular theory, which statement describes the particles in a sample of an ideal gas
the particles are considered to have negligible volume
which statement describes a reaction at equilibrium
the rate of formation of the products must equal the rate of formation of the reactants
which statement describes the particles of an ideal gas, based on kinetic molecular theory
the volume of the gas particles is negligible compared with the total volume of the gas
according to the acid-base theory, a base in an
H+ acceptor
which radioisotope requires long-term storage as a method of disposal, to protect living things from radiation exposure over time
Pu-239