1) strontium-90 is a radioactive isotope which is particularly hazardous. which of the
following statements is true about an atom of strontium-90?
a.it contains 52 neutrons.
b.it contains 52 protons.
c.it contains 90 neutrons.
d.it contains 90 protons.
2) which of the following molecules is polar?
a.ch3-ch3
b.ch2cl-ch2cl
c.ch3-chcl2
d.none of these
3) which of the following is the stannic ion?
a.sn+
b.sn2+
c.sn3+
d.sn4+
4) for which of the following atoms do we not try to apply the octet rule?
a.oxygen
b.nickel
c.sodium
d.xenon
5) in which of the following cases is a polar covalent bond formed?
a.when an electron is transferred from one atom to another
b.when the electrons of a bond are shared equally by the two atoms
c.when the electrons of a bond are shared unequally by the two atoms
d.when a metallic element forms a bond with a non-metallic element
6) which of the following is true in general of all cations?
a.a cation has equal numbers of protons and electrons.
b.a cation has fewer protons than electrons.
c.a cation has more protons than electrons.
d.a cation has more protons than neutrons.
7) when filling a set of orbitals of equal energy which of the following is true?
a.there are no sets of orbitals of equal energy.
b.two electrons will occupy the same orbital rather than separate orbitals.
c.two electrons will occupy different orbitals and have opposing spins.
d.two electrons will occupy different orbitals and have like spins.
8) where does co2 bind to hemoglobin?
a.at the c-termini of the polypeptidesc.at the iron
b.at the n-termini of the polypeptidesd.at the nitrogens of the heme
9) how many orbitals are there in the 4p subshell?
a.1
b.2
c.3
d.4
10) which of the following columns of the periodic table contains no metallic elements?
a.4a
b.5a
c.6a
d.7a
11) which of the chemical elements has the highest ionization energy?
a.f
b.h
c.he
d.u
12) what is the correct name for k2hpo4?
a.dipotassium hydrogen phosphate
b.potassium hydrogen phosphoxide
c.potassium hydrogen phosphate
d.potassium dihydrogen phosphate
13) which greek letter is used in denoting the spatial distribution of charge in a polar
bond?
a.alpha,
b.beta,
c.gamma,
d.delta,