Chemistry Chapter 1 Assignment Questions
Classify each of the samples of matter according to type as indicated
A - Compound (Blue and red) B - Element (Blue only)
Different forms of the same element (such as O2 and O3) are called _____. These forms differ in the way the atoms are bonded together.
Allotropes
A ______ it's a type of chemical equation that shows the electrons either lost or gained by the reactants.
Half-reaction
Half reaction the conservation of mass is reflected by balancing the ______ in both sides of the equation, while the conservation of charge is reflected by adding ___ to the appropriate side of the reaction.
Number of atoms; electrons
Mixture
Physical combination of two or more species
Which of the following elements will form a cation? Select all that apply.
Rb ; Ca
An electrical current is a net movement of _____.
electrons
Match each element with its most common oxidation number (assuming it is involved in a polar/ionic bond).
-2 : O, in compounds other than peroxides +1 : H when bonded to other non metals -1 : F +2 : Mg
Match each element to its most common oxidation number (assuming it is involved in a polar/ionic bond).
-2 : O, in compounds other than peroxides +1 : H when bonded to other nonmetals -1 : F +2 : Mg
Which of the following options correctly interpret the information given? Select all that apply. Molar mass of No2 = 46.0g/mol; molar mass of nitrogen =14.0g/mol; molar mass of oxygen = 16.0g/mol.
1) 2) 3)
Which of the following options correctly describes elements and compounds? Select all the apply.
1) A compound contains two or more different elements 2) Elements and compounds are both pure substances 3) There are many more known compounds than elements
Rank the following elements correctly according to its number of protons, stating with the element that has the least number of protons at the top of the list.
1- He 2- Al 3- Zn 4- Rn
Scientific notation expresses a quantity with a single digit before the decimal point and followed by _____ raised to the appropriate power.
10
1 ppm is _____ times smaller than 1%.
10,000
The atom of chlorine (Cl) has a mass number of 36. The atom has ___ protons and ____ neutrons in its necleus.
17;19
How many significant figures should the answer to the following calculation contain? 2.3x5.46=___.
2
Which of the following ion combinations will result in an ionic compound that has a balanced number of positive and negative charges? Select all that apply.
2 Li^+ and S^2- ; Na^+ and Br^- ; Ca^2+ and 2F^-
An ore is ____.
A rock containing a significant concentration of desirable metal.
Group 1 Group 2 Group 17 Group 18
Alkali metals Alkaline earth metals Halogens Noble gasses
Which of the following formulas for ionic compounds are correct? Select all that apply.
CaO ; Ca3N2
In a given chemical compound, the component ——— are present in ——— proportions by mass, regardless of the source of the compound.
Elements, fixed
Copper occurs in a variety of compounds in ores. Chalcocite is a mineral composed of Cu2 S. In order to extract would Cu Metal from this ore, the Cu^+ ions must ____ electrons and the S^2- ions must ____ electrons.
Gain; lose
Match each solid with the correct description.
Glass : random array of silicon and oxygen linkage throughout the solid Quartz : pure crystallized SiO2 with a highly ordered arrangement at the atomic level
Match each solid to the correct description.
Glass: random array of silicon and oxygen linkage throughout the solid Quartz: pure crystallized SiO2 with a highly ordered arrangement at the atomic level
Which metals could be recovered from electronic devices? Select all that apply.
Gold ; silver
The composition of a mixture may be expressed as a percentage. Percent means part per ____.
Hundred
Silicon is a key component in my Tronic devices. This element is an _____, a type of element also called a ____.
Metalloid ; semiconductor
Solid compounds of metal found in rock and soil called
Minerals
Air Oxygen (O2)
Mixture Pure Substance
Chemist use the ______ as a unit of amount of substance
Mole
10 mm (millimeters) are equivalent to 1 cm (centimeter). To covert 15 cm to mm, you would _____.
Multiply by 10
If a compound is composed of nitrogen and hydrogen atoms in a respective 1-to-3 ratio what is the correct chemical formula for this compound
NH3
Match each element to its correct oxidation number
O in O2 - 0 Na in NaCl - +1 O in H2O - 0 Fe in FeCl3 - +1
Match each element to its correct oxidation number
O in O2 : 0 Na in NaCl : +2 O in H2O : -2 Fe in FeCl3 : +3
Which of the following are allotropes of oxygen?
O3, O2
The chemical formula CCl4 indicates that there is/are ____ carbon atom(s) for every ___\. Chlorine atoms.
One ; four
A rock that contains a significant concentration of one or more desirable metals us called a ____.
Ore
To track the transfer of electrons in both ionic and molecular substances we assign an ____ number to each element involved. This number reflects the charge the element would have if all bonds were ionic.
Oxidation
A process in which a species loses electrons is known as______, where is the process in which a species gains electrons is known as _____.
Oxidation ; reduction
Match each process to the correct description.
Oxidation: loss of electrons Reduction: gain of electrons
Many medals occur as minerals and reconcile. A mineral in which a metal is bonded to oxygen is called a ______, where as a mineral containing oxygen and silicon together is called a ____.
Oxide; silicate
A ____ figure is a digit that represents the accuracy with which an experimental quantity is known
Significant
A "cradle-to-cradle" approach to analysis of the life cycle of an item includes the idea that _____.
The end of the life cycle of one item leads naturally into the beginning of the life cycle of another.
Electric current is ____.
The movement of charged particles such as electrons or ions
When a electronic device is recycled, the metals are recovered by ____.
Treatment with strong acid
In the compound MgO, the Mg ion has a charge of _____, while the O ion has a charge of ___.
+2;-2
If a mixture of quartz and bauxite contains 78% quartz, this means that ____.
- 150 g of this mixture contains 117g of quartz - there are 78g of quartz in 100 g of the mixture - there are 78g of quartz for every 22g of bauxite
In most modern touch screens _____.
- A conductive object touching the screen distorts the electric field - layers of conductive wires are sandwiched between insulating surfaces
Which of the flowing options correctly describe the characteristics behavior of the elements in a particular group on the periodic table? Select all that apply.
- Alkali metals and alkaline earth metals make soil and water alkaline. - Noble gases are generally unreactive
Which of the following elements are correctly added to sand when making glass, to improve its thermal properties? Select all that apply
- Aluminum - Boron - Potassium
Which of the following options correctly describe the chemical symbols for elements? Select all that apply.
- Chemical symbols are also called atomic symbols - Chemical symbols are abbreviations for elements named for properties, planets, places, and people.
In the compound CrCl3 _____. Select all that apply.
- Cl has a -1 charge - Cr has a +3 charge
Which of the following statements correctly describes how conversion factors are used in calculations? Select all that apply.
- Conversion factors are relationships used to express the same quality in different units - all unit should cancel except for those required for the answer when multiplying by a conversion factor - The conversion factor should be selected so that the units in the original quantity cancel with one of the units in the factor
Hematite is an iron ore containing Fe2 O3. To obtain solid Fe metal from this ore ____. Select all that apply.
- O2- ions will be oxidized - the balances half-reaction is Fe^3+ + 3e^- —> Fe - Fe^3+ ions must be reduced
Which of the following statements correctly describe the rules for assigning oxidation numbers (abbreviated as O. N.)? Select all that apply.
- The O. N. For a monatomic ion is the same as its charge. - the sum of the oxidation numbers for the he atoms in a neutral compound is zero.
Which of the following statements correctly describe the atomic number of an element? Select all that apply.
- The atomic number is equal to the number of protons in the nucleus - each element has its own unique atomic number
Which of the following form the focus of the "cradle-to-grave" approach to consumer goods? Select all that apply.
- The energy consumed to produce the goods - The role materials from which the goods are made - The waste products created when the goods are made
Which of the following options correctly describe the mass number of an element? Select all that apply.
- The mass number of a particular element may vary - The mass number is given by the sum of the protons and neutrons in the nucleus
Select the options that correctly reflect the mass ratio and mass percentages of the elements in SO3
- The mass percentage of O is 60.0% - The mass ratio of S is 0.400
Which of the following options correctly describe a half reaction? Select all that apply.
- The overall process occurring in the redox reaction include both the oxidation and reduction reaction. The two parts are each known as half reactions. - A half-reaction shows the electrons gained by the reactants in the redox reaction. - A half-reaction shows the electrons lost by the reactants in a redox reaction.
I high of the following options correctly describe mixtures? Select all that apply.
- the proportions of the components can vary. - the components can be separated by physical means.
In the compound MgO, the Mg ion has a charge _____, while the O ion has a charge of ___.
+2;-2
What are the environmental challenges to extracting metals from recycled electronic devices? Select all that apply.
- Contaminated groundwater could contribute to an increase of cancers in surrounding communities - Groundwater could be contaminated with heavy metals - The solvents used to remove the plastic are not generally environmentally friendly.
Which of the following options correctly describe silica? select all that apply.
- Silica is a naturally occurring substance. - Quartz is a form of silica. - silica has a well-ordered structure of repeating linkage between Si and O.
Which of the following options correctly describe silica? Select all that apply.
- Silica is a naturally occurring substance. - Silica has a well-ordered structure composed of repeating linkages between Si and O. - Quartz is a form of silica.
Which of the following examples has the oxidation number (O.N.) of the given element been assigned correctly? Select all that apply.
- The O.N. for S in SO2 is +4 - The O.N. for Iron in FeO is +2
Which of the following options correctly describe the mass number of an element? Select all that apply.
- The mass number of a particular element may vary. - The mass number is given by the sum of the protons and neutrons in the nucleus.
Which of the following options correctly describe the mass number of an element? It's like all that apply.
- The mass number of a particular element may very - The mass number is given by the sum of the protons and neutrons in the nucleus
Select the options that correctly reflect the mass ratio of the mass percentages of the elements in SO3
- The mass percentage of O is 60% - The mass ratio of S is 0.400
A material will conduct electricity more readily if ____.
- The material is made of metal - it's electrons are mobile
Which of the following options describes the correct format used when writing a chemical formula of a substance? Select all that apply.
- The number of atoms of a particular element is indicated by the subscript - A chemical formula is symbolic way to represent the composition of a substance
Which of the following statements correctly describe molar mass? Select all that apply.
- The periodic table can be used to calculate the molar mass of any substance - The molar mass of oxygen is 16.00 g/mol. This means that one mole of oxygen atoms has a mass of 16.00g. - The molar mass of a molecular structure is the mass per mole of its molecules
Which of the following options correctly describe atoms?
- compounds contains two or more different types of atoms - atom are extremely small - an atom is the smallest unit of an element that can exist as a stable independent entity
Synthetic sapphire _____. Select all that apply.
- denser than glass - is produced by heating aluminum oxide powder to a very high temperature
Synthetic sapphire _____. Select all that apply.
- is produced by heating aluminum oxide powder to very high temperatures - is denser than glass
The oxidation state of an element ______.
- reflects the way electrons are transferred during a reaction - reflects its charge if it is in present as an ion - is determined by the way it is bonded
Which of the following reflects the correct procedure to calculate the molar mass of CH2Cl2?
12.0 + 2(1.0)+2(35.5)=85.0 g/mol
The molar mass of CH2 Cl2 is 85.0 g/mol, well the molar mass of carbon is 12.0 g/mol. The percent of carbon in this compound is correctly expressed as ____.
12.0 g C / 85.0g CH2Cl2 x 100%
Which of the following reflects the correct procedure to calculate the molar mass of CH2CL2Cl2?
12.0+2(1.0)+2(35.5)=85.0g/mol
Which option shows the correct set up to convert from 20 nm to M given that, 1 nm = 1×10 to the -9th M?
20 nm x 1 x10 to the -9 m / 1mn
Express 2.6 x 10^4 in decimal notation.
26,000
The correct answer to the mathematical expression 10^16 x10^14 is 10——. The correct answer to the mathematical expression 10^16 / 10^14 is 10——.
30;2
The smallest unit of an element that can exist as a stable independent entity is a ____.
Atom
A molecule is an independent structure composed of two or more ________ chemically bonded together.
Atoms
Match each compound correctly to its molecular mass.
CCl4 - 154.0 g/mol PF3 - 88.0 g/mol SO2 - 64.1 g/mol
Which of the following ion combinations will result in an ionic compound that has a balance number of positive and negative charges? Select all that apply.
Ca^2+ and 2 F ; Na^+ and Br^- ; 2 Li^+ and S^2-
The periodic table is organized such that elements with similar_____ properties fall into vertical columns called____.
Chemical; groups
Match each element to the appropriate charge for its ionic form
Cl - -1 Sr - +2 S - -2 Al - +3
Most elements occur in nature as ___.
Compounds
Classify each material according to its ability to enable the flow of electricity.
Conductor: - silver - copper - silver Semiconductor: - Si - GaAs - CdS Insulator: - plastic - concrete
Match each type of material to the correct description.
Conductor: enables the flow of electricity Insulator: does not allow the flow of electricity
Element Compound
Contains only one type of atom Consists of two or more elements, chemically bound
And approach to analyzing do you lifecycle of an item beginning with them raw materials from which it is made to its ultimate disposal is called the ____ approach.
Cradle-to-grave
Match each type of solid with correct description
Crystal : highly ordered arrangement of constituted particles Amorphous : disordered/random arrangement of constituted particles
The conversion factor is ratio of _______ quantity is used to express in quality in different units of measurement. Multiplying by a conversion factor is the same as multiplying a quantity by___ because the numerator in denominator are equivalent.
Equivalent; 1
True or false: when mathematically manipulating pieces of data the quantity with the most significant figures determines the accuracy of the calculation.
False
Which of the following equations are represents a oxidation half-reaction?
Fe^2+ —> Fe^3+ + e^-
Pure Substance
For of matter with a definite composition
A chemical ——— represents the elementary composition of any pure substance
Formula
Metal Nonmetal Metalloid
Good conductor of heat and electricity Poor conductor of heat and electricity Has Properties between those of metals and nonmetals
Silica glass is made by ____.
Heating sand to a temperature high enough to melt it and then cooling the liquid until it hardens.
A ____ mixture is uniform throughout, whereas a ____ is not uniform and different components can be distinguished.
Homogeneous; heterogeneous
In a glass of flat coca-cola, the cola is considered a _____ mixture because its composition is ______.
Homogeneous; uniform
Homogeneous: and Heterogeneous
Homogenous: - Salt water - Air Heterogeneous - pasta salad - Bean soup - soil mixed with rocks
I need typical periodic table the rear earth metals are found _____.
In the first row below the main body of the table
The accuracy of a calculation is limited to the quantity that has the _____ number of significant figures.
Least
Each element is given compound comprises a fixed percent by —— of the compound.
Mass
To balance a half reaction the number and type of each element present is balanced to reflect the conservation of_____ in the reaction. Electrons are added to the appropriate side of the equation to reflect the conservation of ____.
Mass ; charge
The ____ number of an atom is equal to the total number of protons and _____ in the nucleus of the atom.
Mass ; neutrons
Match each element in the compound NH3 toits correct mass ratio and mass percentage
Mass ratio of N - 0.824 Mass percentage of N - 82.4 Mass ratio of H - 0.176 Mass percentage of H - 17.6
Molecular compound: and Ionic compound:
Molecular compound: - composed of molecules - formed when nonmetals combine Ionic compound - formed when metals combine with nonmetals - contains no molecules
Which of the following elements commonly occur as a diatomic molecules? Select all that apply
Nitrogen; oxygen; hydrogen; fluorine
Match each group on the periodic table with the characteristic behavior of the elements belonging to it.
Noble Gases: generally unreactive Alkali Metals: make soul and water alkaline Alkaline Earth Metals: result in hard water
S Ca Si
Nonmetal Metal Metalloids
Match each component of the atom with the correct description
Nucleus - small region that contains almost all the mass of an atom. Electron - negatively charged particle Proton - positively charged particle found within the center of the atom Neutron - uncharged dense particle located in the center of the atom
Classify each element correctly according to type
O3 - element H2O - compound Air - mixture
The chemical formula CCl4 indicates that there are—— carbon atoms for every—— chlorine atoms
One, Four
Each element has a unique number of ______, which is called the atomic number. For a neutral atom this number is also equivalent to the number of ____ present.
Protons; electrons
Pure Substance: Mixtures:
Pure Substance: - Hydrogen Gas - A pure Silver coin - H2O Mixtures: - gold plated errings - salt water
Na N S Si Ag
Sodium Nitrogen Sulfur Silicon Silver
Managing human consumption of natural resources so that these resources are not exhausted is called _____.
Sustainablity
Extracting Metals by recycling electronic devices _____.
Taps into a source that is far more concentrated than metal ores mined from the ground
Which statement correctly describes the procedure used to predict the ion formed by group 1 and group 2 elements?
The metal loses enough electrons to attain the same number as the nearest noble gas.
Chemistry is the study of matter, which is commonly defined as anything that has ____ and occupies _____.
mass and space
We often use the units of ppm, ppb, ppt to Express very low concentrations. Match each unit to the correct definition.
ppm : parts per 10^6 parts ppb : parts per 10^9 parts ppt : parts per 10^12 parts
Classify each compound correctly as either a covalent or ionic compound.
Covalent: - CO2 - N2O5 - PCL3 Ionic - NiO - NaBr - FeCl3