the sac
All matter is composed of elements. Approximately how many elements are there?
100
What type of element has the following general properties: solid at room temperature, high luster, good conductor of heat and electricity, malleable and ductile?
metal
An ion is an electrically charged atom or group of atoms.
true
All gases exist as diatomic molecules
false
Water is a chemical element
false
More substances exist as compounds than as element
true
elements are the basic building blocks of all substances
true
The halogens are the only periodic group that contains all three phases of matter under normal conditions.
True
Bromine is a solid at room temperature.
False
Groups or families of elements are arranged in rows in the periodic table. These elements have similar chemical properties.
False
The elements in Groups 1B – 8B are known as the transition elements.
True
Alkali metals are shiny, ductile, good conductors of heat and not very reactive.
False
Which type of element has the following general properties: low melting point and density, lacks luster, poor conductor of heat and electricity, and brittle?
nonmetal
List the following in order of increasing number of oxygen atoms represented:
A) 12 CaCO3
B) 8 Ca(OH)2
C) 6 Ca3(PO4)2
D) Ca(NO3)2
D < B < A < C
On the periodic table vertical columns contain elements with similar properties. These vertical columns are called ___.
groups
The elements on the current periodic table are placed in order of increasing ___.
atomic number
The halogens are in group ___.
7A
The alkaline earth metals are in group ___.
2A
The alkali metals are in group ___.
1A
Which of the following is a member of noble gases?
neon
Which symbol represents a transition metal?
Tc
Which is a nonmetal?
S
The smallest particle of an element that can exist is called a(n) ___.
atom
Which is a metalloid?
B
Which element is not reactive?
Neon
Which element forms diatomic molecules?
Chlorine
Which element forms diatomic molecules?
Bromine
A distinct substance composed of two or more elements combined chemically in a definite proportion by mass is a
compound.
The charge of a cation is ___.
positive
The symbol for cobalt is ___.
Co
How many different elements are present in the compound CoCl2?
2
How many different elements are present in the compound Fe2(SO4)3?
3
How many atoms of oxygen are indicated in the formula Fe(NO3)3?
9
The smallest particle of an element that can enter into a chemical reaction is a(n) ___.
atom
How many atoms are indicated in the formula Ca3(PO4)2?
13
What is the total number of hydrogen atoms present in the compound CH3COOH?
4
What is the total number of atoms present in the compound represented as Mg(NO3)2?
9
How many atoms of hydrogen are present in the compound represented as Al(H2PO4)3?
6
Which of the following is a compound?
water
What is the total number of oxygen atoms present in Fe2(SO4)3?
12
Which is a characteristic of all nonmetals?
poor conductors of heat
The number of nonmetallic atoms in Al2(SO3)3 is ___.
12
If an element is a metal, one would expect it to be
ductile
Which would be used in semiconductors?
silicon
Most elements are rare. How many elements make up approximately 99% of the mass of the earth’s crust, oceans, and atmosphere?
10
K is the symbol for the element ___.
potassium
Which of the following represents an element?
N2
Which is not a characteristic of metals?
brittle
Which of the following formulas contains the fewest oxygen atoms?
Na2CO3
The formula C3H5(OH)3 contains
14 total atoms.
The symbol for one crystalline form of sulfur is S8. This symbol indicates
one molecule composed of eight atoms.
Which of the following is an anion?
Cl-
Which element is not a gas at normal temperature and pressure?
carbon
Which of the following is a cation?
Fe+3
The symbol P corresponds to the element ___.
phosphorus
The most abundant element in the earth’s crust, oceans, and atmosphere is ___.
oxygen
Which does not exist as diatomic gas?
bromine
Which of the following is a metalloid?
Si
Which of the following is the correct symbol for iron?
Fe
Which of the following cannot be broken down by chemical or physical means?
element
Which element is malleable, ductile, and a good conductor of electricity?
Au
Which element is brittle and a poor conductor of electricity?
S
The smallest uncharged individual unit of a compound is a(n) ___.
molecule
The ultimate particle of water is a(n) ___.
molecule
An ionic compound is held together by
attractive forces between ions of different charges.
How many atoms of calcium are indicated in the formula Ca(NO3)2?
1
Which element is a liquid at room temperature?
Bromine
The nitrate group is NO3–. How many nitrate groups are in the formula NaNO3?
1
The sulfate group is SO4–2. How many sulfate groups are in the formula Fe2(SO4)3?
3
Palladium is a member of the
transition metals.
How many hydrogen atoms are in the molecule C3H5(OH)3?
8
Which cannot be broken down chemically or physically into a simpler substance?
copper
Which is the most abundant element in the universe?
hydrogen
Which chemical symbol is properly written?
Cu
Which of the following is a noble gas?
argon
Which of the following is an alkali metal?
sodium
Which of the following is an alkaline earth metal?
magnesium
Which element is a liquid at room temperature?
mercury
Which of the following is a halogen?
chlorine
Which of the following is a transition element?
manganese
Which of the following elements is from a representative group?
S
Which element of the following is most similar to calcium?
strontium
Which element of the following is most similar to bromine?
chlorine
Which of the following is best classified as a semiconductor?
boron
Which of the following does not exist as a diatomic gas?
argon
What is the symbol of the element that is classified as a metalloid and is in Group IVA and period 3?
Si
Element with the atomic number 24 can be described as
ductile.
What is the atomic number of potassium?
19
The majority of the elements are ___.
metals
What is the name of the element with an atomic number of 24?
chromium
What is the symbol of the element that is classified as an alkali metal and is in period 4?
K
What is the name of the element with an atomic number of 80?
mercury
One of the properties of metals is their ductility. This means that
they can be drawn into wires.
Which of the following alternatives does not represent a molecule?
Ga
Consider the chemical formula for one molecule of methane, CH4. If instead of one molecule we had 10 molecules of methane, how many carbon atoms would be present?
10
Consider the chemical formula for one molecule of table sugar, C12H22O11. If instead of one molecule of sugar we had 5, how many oxygen atoms would be present?
55
Consider the chemical formula for one unit of aluminum sulfate, Al2(SO4)3. How many total atoms would be present in 22 units of aluminum sulfate?
374
One unit of potassium oxide contains 2 atoms of potassium for every atom of oxygen. What is the chemical formula for potassium oxide?
K2O
One unit of aluminum sulfide contains 2 atoms of aluminum for every three atoms of sulfur. What is the chemical formula for aluminum sulfide?
Al2S3