chemistry test one
what is the correct answer for the calculation of a volume (in mL) with measured numbers 28.58/16x8.02
0.22 ml
which of the following measurements has 3 significant figures?
0.510 m
how many electrons do the alkali metals possess?
1
what is the conversion factor for the relationship between milliliters and centimeters?
10mm/1cm
how many protons are in the isotope of sodium with a masss number of 25?
11
Consider an isotope of sodium with a mass number of 25. The number of neutrons in this isotope of sodium is
14
which of the following numbers contains the designated correct number of significant figures?
156 000 3 significant figures
the max number of electrons that may occupy the third electron energy level is
18
what is the metric relationship between grams and micrograms?
1g=100 000 000 ug
what is the electron arrangement for aluminum
2,8,3
what is the electron arrangement for potassium (atomic number 19)?
2,8,8,1
what is the. correct. electron arrangement for lithium atom?
2.1
which of the following examples illustrates a number that is correctly rounded to three significant figures?
20.0332 g to 20.0 g
which of the answers for the following conversions contain the correct number of significant figures?
24.95 min x 1hr/60 min = 0.4158 hr
which of the following conversion factors is a measured number?
25 miles/gallon
how many significant figures are in the number 0.00208?
3
how many valence electrons are in the electron dot symbols for the elements in group 3A (13)?
3
how many valence electrons does an atom of Al possess?
3
the number of electron energy levels in a magnesium atom is
3
the number of electrons in the outer energy level of a neutral atom of boron (atomic number 5) is
3
Consider a neutral atom with 30 protons and 34 neutrons. The atomic number of the element is
30
12 is what percent of 36?
33%
what is the mass number of an atom of potassium that has 20 neutrons?
39
The correct symbol for the isotope of potassium with 22 neutrons is a. 41/19K b. 19/41K c. 37/15K d. 15/37K e. 22/19K
41/19 K
A calculator answer of 423.6059 must be rounded off to three significant figures. What answer is reported?
424
which of the following gives the correct numbers of protons, neutrons, and electrons in a neutral atom of 118/50 Sn?
50 protons, 68 neutrons, 50 electrons
Consider a neutral atom with 30 protons and 34 neutrons. The mass number of the element is
64
how many valence electrons do the halogens possess?
7
Which is a noble gas?
Argon
Which element would have physical and chemical properties similar to chlorine?
Br
what is the symbol of the element in group 4a (14) and period 2?
C
what is the element with electron arrangement 2,8,7?
Cl
place the following elements in order of increasing atomic radius. P Ba Cl
Cl < P < Ba
place the following in order of decreasing IE1 (ionization energy for the first electron) Cs Mg Ar
Cs > Mg > Ar
Identify the noble gas in the following list
Helium
place the following in order of increasing radius Br- Na+ Rb+
Na+ < Rb+ < Br
place the following in order of increasing atomic radius. As O Br
O < Br < As
which reaction represents the first ionization of O?
O(g) ---> O+(g) + e
what element has the electron arrangement 2,8,4?
Silicon
which reaction represents. the second ionization of Sr?
Sr+(g) ---> Sr2+(g)+e-
which of the following is not true for the atoms 13N, 14N, 15N?
They all have the same mass number
which of the following descriptions of a subatomic particle is correct?
a proton has a positive charge and a mass of amu 1
One way to enhance your learning in chemistry is to
all of the above
in an atom, the nucleus contains
all the protons and neutrons
The elements lithium, sodium, and potassium
are in the same group
The elements sodium, magnesium, and silicon
are in the same period of elements
one example of a chemical used in toothpaste is
calcium carbonate
Water (H20) is an example of a(n)
chemical
identify the yellow-green gas that is used as a disinfecting agent
chlorine
the atomic size of atoms
decreases going across a period
the metallic character of elements
decreases going across a period
the ionization of atoms
decreases going down within a group
the primary substances of which all other things are composed are
elements
The number of dots in the electron dot symbol of nitrogen is a. one. b. two. c. three. d. four. e. five.
five
the number of significant figures in the measurement of 45.030 mm is
five
The number of dots in the electron dot symbol of carbon is a. one. b. two. c. three. d. four. e. five.
four
idenitfy the metalloid in the following list
germanium
Au is the symbol for
gold
In the number 12.345, the 4 is in the ________ place.
hundreths
When filling degenerate orbitals, electrons fill them singly first, with parallel spins is known as
hunds rule
there is more traffic between 8 and 9 in the morning because most people start work at 9. this would be a
hypothesis
valence electrons are electrons located
in the outermost energy level of an atom
the atomic size of atoms
increases going down within a group
the metallic character of elements
increases going down within a group
the number of valence electrons found in an atom of a group A element is equal to
its group number
which of the following is a measurement of mass in the metric system?
kilogram
which of the following is the largest unit?
kilometer
a value of 345 mm is a measurement of
length
which of the following is not a chemical?
light
which of the following is the basic unit of volume in its metric system?
liter
what is characteristic of nonmetals?
low melting points
titanium dioxide is a chemical in toothpaste used to
make toothpaste white
number of neutrons in an atom
mass number - atomic number
which of the following is the smallest unit?
microgram
cubic centimeter (cm3 or cc) has the same volume as
milliliter
which is not a characteristic of the group1A (1) elements *(alkali metals)?
most of them are liquids at room temp
which of the elements in a non metal?
nitrogen
the mass number of an atom can be calculated from
number of protons plus neutrons
you notice that there is more traffic between 8 and 9 in the morning. this would be a
observation
The production of smog from NO gas requires ________.
oxygen
When a part of the body is injured, substances called ________ are released.
prostaglandins
The atomic number of an atom is equal to the number of
protons
In this list, which substance can be classified as a chemical? a. salt b. sleep c. cold d. heat e. temperature
salt
what element is a metalloid?
silicon
Sodium fluorophosphate is a chemical used in toothpaste to ________.
strengthen tooth enamel
The element in this list with chemical properties similar to magnesium is a. sodium. b. boron. c. carbon. d. strontium. e. chlorine.
strontium
which element is a metal?
strontium
which of the following is a chemical?
sugar
In the number 12.345, the 1 is in the _____ place. a. tens b. ones c. tenths d. hundredths e. thousandths
tens
In the number 12.345, the 3 is in the ________ place.
tenths
which is a characteristics of the modern periodic table?
the elements in each group should have similar chemical properties
ionization energy
the energy required to remove an the least tightly bound electron
the atomic mass of an element is equal to
the mass of an average atom
The electron arrangement of any particular atom shows
the number of electrons in each energy level
Isotopes are atoms of the same element that have different
the same atomic number but different numbers of neutrons
in an electron dot symbol of an element, the dots are used to represent
the valence electrons
Group 8A (18) elements are:
unreactive and rarely found in combination elements with other elements
A value of 36 mL is a measure of
volume
The amount of space occupied by a substance is its
volume
The measurement of the gravitational pull on an object is its
weight
