Ch. 3 Chemistry test

T/F? Alkali metals are shiny, ductile, good conductors of heat and not very reactive.

False

T/F? All gases exist as diatomic molecules.

False

T/F? Bromine is a solid at room temperature.

False

T/F? Groups or families are arranged in rows in the periodic table. These elements have similar chemical properties.

False

T/F? In nature most matter exists as pure substances.

False

T/F? The elements are distributed uniformly in nature.

False

T/F? The names of all elements are derived from ancient Greek and Latin.

False

T/F? Water is a chemical element.

False

T/F? An ion is an electrically charged atom or group of atoms.

True

T/F? In nature, hydrogen exists as a diatomic molecule.

True

T/F? In the periodic table, metalloids are located between metals and nonmetals.

True

T/F? The elements in Groups 1B-8B are known as the transition elements.

True

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? a. 10 b. 1 c. 4 d. 40

a. 10

One unit of potassium oxide contains 2 atoms of potassium for every atom of oxygen. What is the chemical formula for potassium oxide? a. K20 b. KO2 c. P2O d. K2O2

a. K2O

K is a member of the a. alkali metals b. alkaline earth metals c. transition metals d. metalloids

a. alkali metals

Which cannot be broken down by chemical or physical means a. aluminum foil b. salt solution c. alcohol d. water

a. aluminum foil

The smallest particle of an element that can exist is called a(n)... a. atom b. ferrule c. neutron d. electron

a. atom

Which element of the following is most similar to bromine a. chlorine b. radium c. cesium d. zinc

a. chlorine

What is the name of the element with an atomic number of 24? a. chromium b. carbon c. cerium d. californium

a. chromium

The law of definite composition pertains to... a. compounds composed of elements b. mixtures composed of compounds c. compounds composed of mixtures d. mixtures composed of elements

a. compounds composed of elements

Which of the following cannot be broken down by chemical or physical means a. element b. compound c. heterogeneous mixture d. homogeneous mixture

a. element

Which element has the following general properties: low melting point/ density, and poor conductor of heat and electricity? a. nitrogen b. sodium c. aluminium d. copper

a. nitrogen

Which of the following is an alkali metal? a. sodium b. neon c. magnesium d. chlorine

a. sodium

What is the atomic number of potassium a. 15 b. 19 c. 46 d. 50

b. 19

How many different elements are present in the compound CoCl2 a. 1 b. 2 c. 3 d. 4

b. 2

How many metal atoms are present in the compound represented as Al2O3 a. 1 b. 2 c. 3 d.5

b. 2

Which chemical symbol is properly written a. CA b. Cu c. CO d. CL

b. Cu

What is the symbol of the element that is classified as an alkali metal and is in period 4? a. Ca b. K c. Br d. Na

b. K

What is the symbol of the element that is a noble gas and is in period 4? a. Br b. Kr c. K d. Ca

b. Kr

The elements on the current periodic table are placed in order of increasing... a. density b. atomic number c. boiling point d. atomic mass

b. atomic number

Which of the following is best classified as a semiconductor a. carbon b. boron c. lead d. sodium chloride

b. boron

Which is the abundant element in the universe a. oxygen b. hydrogen c. water d. silicon

b. hydrogen

Which element can be used as a semiconductor in electronic devices a. carbon b. silicon c. aluminum d. phosphorus

b. silicon

One of the properties of metals is their ductility. This means that... a. they can be heated to very high temperatures b. they can be drawn into wires c. they are good conductors of electricity d. they can be melted

b. they can be drawn into wires

Based on the chemical formula Mg3(AsO4)2, choose the alternative that lists the number of atoms and the names of each of the elements present in the compound. a. 3 atoms of magnesium, 1 atom of astatine, 8 atoms of oxygen b. 3 atoms of magnesium, 2 atoms of antimony, 8 atoms of oxygen c. 3 atoms of magnesium, 2 atoms of arsenic, 8 atoms of oxygen d. 6 atoms of magnesium, 2 atoms of arsenic, 8 atoms of oxygen

c. 3 atoms of magnesium, 2 atoms of arsenic, 8 atoms of oxygen

How many hydrogen atoms are in the molecule C3H5(OH)3 a. 3 b. 5 c. 8 d. 15

c. 8

What is the total number of atoms present in the compound represented as Mg(NO3)2 a. 3 b. 5 c. 9 d. 10

c. 9

Which element is malleable, ductile, and a good conductor of electricity a. S b. B c. Au d. C

c. Au

What is the symbol of the element that is an alkaline earth metal and is in period 2? a. F b. Li c. Be d. Mg

c. Be

the law of multiple proportions states that... a. atoms of one element may combine in different rations to form more than one compound b. atoms of one element may combine in diff. rations to form the same compound c. atoms of two or more elements may combine in different ratios to form more than one compound d. atoms of two or more elements may combine in diff. rations to produce the same compound

c. atoms of two or more elements may combine in diff. rations to form more than one compound

Which element is a liquid at room temperature? a. fluorine b. chlorine c. bromine d. iodine

c. bromine

Which of the following does not exist as a diatomic gas? a. fluorine b. nitrogen c. iodine d. chlorine

c. iodine

Which element is not reactive? a. hydrogen b. oxygen c. neon d. lithium

c. neon

K is the symbol for the element... a. kalium b. kadmium c. potassium d. krypton

c. potassium

All matter is composed of elements. Approximately how many elements are there? a. 4 b. 0 c. 68 d. 100

d. 100

How many non-metallic atoms are present in the compound represented as Al(HSO4)3 a. 6 b. 9 c. 12 d. 18

d. 18

The halogens are in group... a. 1A b. 2A c. 3A d. 7A

d. 7A

How many atoms of oxygen are indicated in the formula Fe(NO3)3 a. 1 b. 3 c. 6 d. 9

d. 9

Which of the following alternatives does not represent a molecule? a. O2 b. NO c. H20 d. Ga

d. Ga

Which pair of formulas illustrates the law of multiple proportion? a. CH3Cl and CH3OH b. H20 and HOH c. CuCl2 and CuBr d. H2O and H2O2

d. H2O and H2Os

What is the symbol of the element that is classified as a metalloid and is in Group 6A and period 3 a. C b. Ge c. Ti d. Si

d. Si

The law of definite composition states... a. a compound always contains one element physically combined in variable proportions by mass b. a compound always contains one element chemically combined in a definite proportion by mass c. a compound always contains two or more elements physically combined in variable proportions by mass d. a compound always contains two or more elements chemically combined in a definite proportion by mass

d. a compound always contains two or more elements chemically combined in a definite proportion by mass

Which of the following is a noble gas a. oxygen b. iron c. nitrogen d. argon

d. argon

Which element forms diatomic molecules? a. sulfur b. neon c. calcium d. chlorine

d. chlorine

A distinct substance composed of two or more elements combined chemically in a definite proportion by mass is a... a. homogeneous mixture b. heterogeneous mixture c. solution d. compound

d. compound

Which cannot be broken down chemically or physically into a simpler substance a. sugar b. salt c. seawater d. copper

d. copper

Element with the atomic number 24 can be described as a. a poor conductor of heat b. a poor conductor of electricity c. highly reactive d. ductile

d. ductile

Which type of element has the following general properties: solid at room temperature, high luster, good conductor of heat and electricity, malleable and ductile? a. metalloid b. noble gas c. nonmetal d. metal

d. metal

The most abundant element in the earth's crust, oceans, and atmosphere is... a. water b. hydrogen c. iron d. oxygen

d. oxygen

Which element of the following is most similar to calcium a. silicon b. potassium c. scandium d. strontium

d. strontium