Chemistry 9th grade final review
1 Cheese + 2 Bread --> 1 Grilled cheeseHow many grilled cheeses can you make with 26 slices of bread and 14 pieces of cheese?
13
What is the atomic mass of "F"
19
Which electron configuration belongs to Chlorine (Cl)?
1s2 2s2 2p6 3s2 3p5
What electron configuration matches an oxygen atom?
1s22s22p4
How many electrons can the s sublevel hold?
2
Mg + ___ HCl → MgCl2 + H2
2
2H2 + O2 → 2H2OHow many moles of oxygen are consumed if 8 moles H2 are used?
4
How many atoms of aluminum are on each side of the following equation: 4Al + 3O2 --> 2Al2 O3
4
The Formula to make S'mores is:2C + 1M + G2 → C2MG2. If you have 5 Marshmallows (M), 9 Chocolate Pieces (C), and 9 Graham Cracker Halves (G), how many S'mores can you make?
4
CH4 + 2 O2 → CO2 + 2 H2OHow many moles of carbon dioxide are produced from the combustion of 110 g of CH4?
6.85 mol
Cl: How many valence electrons in this structure?
7
How many atoms are there TOTAL in:H2SO4
7
What is the number of protons that the element in this image contain?
7
SiO2 + 3C → SiC + 2COI need to add 8 moles of Carbon to the reaction. How many grams of Carbon should I weigh?
96 g
Generally, the number of neutrons ____ the number of protons in an atom.
=
The element with the lowest electronegativity in Period 3 is -
Ar
Atoms joined together by SHARING electrons are?
Covalent bonds
List the following in order of weakest to strongest ionization energy.P, Cs, Co, Sr
Cs, Sr, Co, P
2Pb(NO3)2 --> 2PbO + 4NO2 + O2
Decomposition
One reactant into several products.
Decomposition
What type of chemical reaction is this?Al(OH)3 → Al2O3 + H2O
Decomposition
Define a liquid.
Definite volume, indefinite shape
When a gas changes directly to a solid, the process is known as what?
Deposition
Ions in two compounds switch.
Double Replacement
The following is what type of reaction:PbCl2 + AgNO3 → Pb(NO3)2 + AgCl
Double Replacement
3KOH + H3PO4 --> K3PO4 + 3H2O
Double displacement
What does the Law of Conservation of Mass state?
Matter cannot be gained or lost in a chemical reaction.
Who developed the Periodic Table?
Mendeleev, who was a chemist and teacher
Which type of bond creates a "pool" of electrons between atoms?
Metallic Bonds
What is the limiting reactant if 10 moles of NH3 react with 30.0 moles of NO?4 NH3+6 NO --> 5 N2 + 6 H2O
NH3
Covalent compounds
Share electrons
As you move down the periodic table atoms get bigger. This is because ____________.
The atoms have more energy levels
Calculate the number of moles of Al2O3 that are produced when 0.60 mol of Fe is produced in the following reaction.2Al(s)+3FeO(s)->3Fe(s)+Al2O3(s)a. 0.20b. 0.40c. 0.60d. 0.90
a. 0.20 mol 0.60molFe*1molAl2O3/3molFe=0.20 mol Al2O3
How are covalent bonds explained?
When the atom shares an electron with an another atom
When does a chemical reaction stop?
When the limiting reactant is used up.
How many moles of H3PO are produced when 71g P4O10 reacts completely to form H3PO4?a. 0.635 molb. 1.00 molc. 4.00 mold. 16.0 mol
b. 1 mol
Which of the following statements is true about the following reaction? 3NaHCO3(aq) + C6H8O7(aq) --> 3CO2(g) + 3H2O(s) +Na3C6H5O7(aq)a. 22.7 L of CO2 (g) are produced for every liter of C6H8O7 (aq) reactedb. 1 mole of water is produced for every mole of carbon dioxide producedc. 6.02 x 10^23 molecules of Na3C6H5O7 (aq) are produced for every NaHCO3 (aq) usedd. 54 g of water are produced for every mole of NaHCO3 (aq) produced
b. 1 mole of water is produced for every mole of carbon dioxide produced
Metallic copper is formed when aluminum reacts with copper(II) sulfate. How many grams of metallic copper can be obtained when 54.0 g of Al react with 319 g of CuSO4 ? Al + 3CuSO4--> Al2 (SO4 )3+ 3Cu
b. 127 g
How many liters of NH3, at STP, will react with 5.3g of 02 to form NO2 and water.?
b. 2.12 liters of NH3
What atom matches this electron configuration?1s22s22p63s23p64s23d10
Zinc
Choose the correct shortcut configuration for iodine.
[Kr]5s24d105p5
How many liters of NH3 are needed to react completely with 30.0 L of NO (at STP)? 4HN3(g) + 6NO(g) ----> 5H2(g) +6H2O(g)a. 5.0 Lb. 20.0 Lc. 7.5 Ld. 120.0 L
b. 20.0 L
Iron(III) oxide is formed when iron combines with oxygen in the air. How many grams of Fe2O3 are formed when 16.7 g of Fe reacts completely with oxygen? 4Fe(s) + 3O2(g) --> 2Fe2O3(s)a. 12.0 gb. 23.9 gc. 47.8 gd. 95.6 g
b. 23.9g
When balancing equations a ____ can be placed to the left of a formula of a substance to make the equations balanced
coefficient
The summary at the end of an experiment that explains the results.
conclusion
How many liters of hydrogen gas are needed to react with CS2 to produce 2.50 L of CH4 at STP?4H2(g)+CS2(l) = CH4(g) +2H2S(g)a. 2.50 Lb. 5.00 Lc. 7.50 Ld. 10.0
d. 10.0 L
Hydrogen gas is produced when zinc reacts with hydrochloric acid. If the actual yield of this reaction is 85%? how many grams of zinc are needed to produce 112 l of H2 at STP?
d. 380
How many grams of H3PO4 are produced when 10.0 moles of water react with an excess of P4O10 ? P4O10 (s) + 6H2O(l) --> 4H3PO4 (aq)a. 1.22 gb. 6.7 gc. 147 gd. 653 g
d. 653 g
When glucose is consumed, it reacts with oxygen in the body to produce carbon dioxide, water, and energy. How many grams of carbon dioxide would be produced if 45 g of C6H12O6 completely reactedwith oxygen?a. 1.5 gb. 1.8 gc. 11 gd. 66 g
d. 66 g
The tendency of an atom to attract electrons and acquire a negative charge
electronegativity
Valence electrons are the number of
electrons in the outside shell of the atom
The energies of electrons as they orbit the nucleus of an atom
energy levels
What happens when my glass of water is sitting in the sun and disappears into a gas?
evaporation
Testing a hypothesis often involves a(n):
experiment
Which atom has the largest atomic radius?
francium
______________________ takes place when a liquid changes to a solid.
freezing
Particles (molecules) in a ______________________ have more energy than the other states of matter.
gas
Electronegativity is...
how good an atom is at attracting electrons
Ionization energy is...
how much energy it takes to remove an electron from an atom
A testable explanation to a problem that has not yet been tested.
hypothesis
As you look from left to right across a period, electronegativity
increases
Electronegativity __________ from left to right within a period and __________ from top to bottom within a group.
increases, decreases
This variable in an experiment is the one being changed by the scientist.
independent variable
A bond that forms when electrons are transferred is called a/an
ionic bond
The minimum energy required to remove an electron from the ground state of an atom
ionization energy
The limiting reactant . . .
is used up first.
Bonds that form between two metals are called ______________ bonds.
metallic
Which subatomic particle has a neutral or no charge?
neutron
Energy levels are denoted by:
numbers
You need 2 pieces of bread, 1 tablespoon of peanut butter and 2 tablespoons of jelly to make a sandwich. If you have 10 pieces of bread, 4 tablespoons of peanut butter and 20 tablespoons of jelly, what is the limiting reactant?
peanut butter
When electrons are shared unequally a/an ___________ bond is formed
polar covalent
Which subatomic particle has a positive charge?
proton
The atomic number of an elements is the total number of which particles in the nucleus?
protons
Which form of matter does not take the shape of its container?
solid
As you move across the periodic table atoms tend to get smaller because, ______________.
the atoms have more protons.
There are 4 different types of subshells (orbitals) s,p,d,f.
true
If an atom loses two electrons what charge will it have?
+ 2
If an atom gains one electron what charge will it have?
-1
Balance this equation._CF4 + _Br2 -- _CBr4 + _F2
1,2,1,2
Balance this equation._CH4 + _O2 --> _CO2 + _H2O
1,2,1,2
Balance this equation._SnO2 +_H2-->_Sn +_H2O
1,2,1,2
4 Al + 3 O2 -> 2 Al2O3 How much aluminum would be needed to completely react with 45 grams of O2?
1.875 moles
How many electrons can the d sublevel hold?
10
The electron configuration of an atom is 1s22s22p6. The number of electrons in the atom is
10
2 KClO3 → 2 KCl + 3 O2How many moles of oxygen are produced when 6.7 moles of KClO3 decompose completely?
10.1 mol
B2H6 + 3O2 -->2 HBO2 + 2 H2OWhat mass of O2 will be needed to burn 36.1 g of B2H6?
124 g O2
__ Al + __ FeO → Al2O2 + __ Fe
2, 2, 2
Balance this equation_Al +_HCl --> _H2 +_AlCl3
2, 6, 3, 2
Cl2 + 2 KBr → Br2 + 2 KClHow many grams of potassium chloride can be produced from 356 g of chlorine and 356 g of potassium bromide?
223 g
Which problem is balanced?
2Na + 2H2O --> 2NaOH + H2
which equation represents the reaction of sulfur with oxygen to form sulfur trioxide?
2S+3O2>2SO3
How many Valence electrons
3
For the Balanced Reaction: 3 Mg + 1 Fe2O3 → 3 MgO + 2 Fe; What is the Ratio of moles of MgO to moles Fe?
3 mol MgO / 2 mol Fe
PCl5 + ___ H2O → ___ HCl + H3PO4
4, 5
2Na + 2H2O → 2NaOH+ H2How many grams of hydrogen are produced if 120 g of Na are available?
5.2 g
2 NaClO3 (s) --> 2NaCl (s) +3 O2 (g)12.00 moles of NaClO3 will produce how many grams of O2?
576 g of O2
How many Valence electrons
6
How many atoms of carbon (C) are in C6H12O6?
6
What is the number of valence electrons for Oxygen?
6
an atom with atomic number 6 would have how many protons
6
Which periodic table family could have electrons filling orbitals in the s-block?
Alkaine Earth
Which of the following will have a lower ionization energy than Scandium (Sc)?
Calcium (Ca)
Which of the following will have a higher electronegativity than arsenic (As)?
Carbon (C)
Which of the following elements has the smallest atomic radius?
Chlorine
The electronegativity of Cl is the highest in Period 3. Why?
Cl is the smallest and has the greatest effective nuclear charge
Use the equation 2 Al + 3 Cl2 ---> 2 AlCl3. If 2 moles of aluminum and 2 moles of chlorine are reacted, identify the limiting reactant.
Cl2
Always starts with a Hydrocarbon that reacts with oxygen and produces carbon dioxide and water.
Combustion
C4H12 + O2 → CO2 + H2O
Combustion
Which subatomic particles contribute the least to the mass of an atom?
Electrons
What subatomic particle(s) would be found orbiting the nucleus?
Electrons only
The element with the largest electronegativity in the halogens is -
F
All chemical bonds involve two atoms sharing electrons.
False
The chemical bond formed when two atoms share electrons is called a(an) IONIC bond.
False
Which is NOT a step in the scientific method?
Form a theory
How is a gas defined?
Indefinite shape, indefinite volume
Which type of bond has a transfer of an electron from on atom to another?
Ionic
Which side of a chemical equation os the product side?
Right (after the yields sign)
What term describes a liquid changing to a solid?
Freezing
The state of matter that has no definite size or shape is
Gas
Identify the limiting reagent when 6.00 moles HCl combines with 5.00 moles Mg to form MgCl2.1 Mg + 2 HCl --> 1 MgCl2 + 1 H2
HCl
what happens to the temperature between points D and E
It remains the same.
Which side of a chemical equation is the reactant side?
Left (before the yields sign)
What atom matches this electron configuration?1s22s22p63s2
Magnesium
Which of the following has a full valence shell?
Neon
Is the equation balanced?: 2H2O + O2 --> 4MgO + 3Fe
No
Which type of bond has an equal sharing of electrons?
Non Polar Covalent
1 P4 + 3 O2 --> 1 P4O6What is the limiting reactant if 12 moles of P4 react with 15 moles of O2?
O2
Identify the limiting reagent and the volume of CO2 formed when 11L CS2 reacts with 18 L O2 to produce CO2 gas and SO2 gas at STP.CS2(g) + 3O2(g) --> CO2(g) + 2SO2(g)
O2; 6.0 L CO2
When 12 moles of O2 reacts with 6 moles of C10H8, what is the limiting reactant?1 C10H8 + 12 O2 --> 10 CO2 + 4 H2O
Oxygen
Which type of bond has an unequal sharing of electrons?
Polar Covalent
Elements on the LEFT side of the periodic table will most likely form:
Positive ions
Which subatomic particles contribute the most to the mass of an atom?
Protons and Neutrons
The two sides of a chemical equation are called?
Reactants (left) and Products (right)
3Ca + 2AlCl3 --> 3CaCl2 + 2Al
Single Displacement
One element replaces another in a compound.
Single Replacement
What type a reaction is taking place in this picture?
Single Replacement
Molecules are closest together in a
Solid
Which state of matter has the lowest compressibility?
Solid
What term describes a solid changing to a gas?
Sublimation
What is the little number after an element in a chemical equation called.Example: H2
Subscript
4Si + S8 --> 2Si2S4
Synthesis
The following is what type of reaction:NH3 + HCl → NH4Cl
Synthesis
Two Reactants and One Product
Synthesis
Water can be a solid, liquid, and a gas.
True
Which conversion factor do you use first to calculate the number of grams of CO2 produced by the reaction of 50.6 g of CH4 with O2 ? The equation for the complete combustion of methane is: CH4 (g) + 2O2 (g) --> CO2 (g) + 2H2O(l)a. 1 mol CH4/16.0 g CH4b. 2 mol O2/ 1 mol CO2c. 16.0g CH4/1 mol CO4d. 44.0g CO2/ 2 mol CO2
a. 1 mol CH4/16.0 g CH4
How many grams of chromium are needed to react with an excess of CuSO4 to produce 27.0g Cu?2Cr(s) + 3CuSO4(aq)---->Cr2(SO4)3(aq) + 3Cu(s)
a. 14.7 grams
Methane and hydrogen sulfide form when hydrogen reacts with carbon disulfide identify the excess reagent and calculate how much remains after 36 l of h2 reacts with 12 l of cs2 4 h2 g cs2 g ch4 g 2 h2s g
a. 3 L CS2
Which of the following would be the limiting reagent in the reaction shown below? 2H2(g) + O2(g) --> 2H2O(g)
a. 50 molecules of H2
Which statement is true if 12 mol CO and 12 mol Fe2O3 are allowed to react? 3CO (g) + Fe2O3 (s) ---> 2Fe (s) + 3CO2(g)
a. limiting reagent is CO and 8.0 mol Fe will be formed.
Each row on the periodic table represents:
an energy level
Particles of a liquid
are free to move around one another but still touch.
Where is the element's atomic MASS located?
at the bottom
all matter is made of what
atoms
How many liters of chlorine gas can be produced when 0.98 L of HCl react withexcess O2 at STP? 4HCl(g) + O2(g) -- >2Cl2 (g) + 2H2O(g)
b. 0.49 L
Aluminum reacts with sulfuric acid to produce aluminum sulfate and hydrogen gas. How many grams of aluminum sulfate would be formed if 250 g H2SO4 completely reacted with aluminum?2AL(s) + 3H2SO4 (aq) --> Al2 (SO4)3 (aq) + 3H2 (g)a. 0.85 gb. 290 gc. 450 gd. 870 g
b. 290 g
What is the maximum number of grams of PH3 that can be formed when 6.2 g ofphosphorus reacts with 4.0 g of hydrogen to form PH3 ? P4 (g) + 6H2(g) --> 4PH3 (g)
b. 6.8 g
Calcium oxide, or lime, is produced by the thermal decomposition of limestone in the reaction CaCO3 (s) --> CaO(s) + CO2(g). What mass of lime can be produced from 1.5 x 10^3 kg of limestone?a. 8.4 x 10^5 kgb. 8.4 x 10^2 kgc. 8.4 kgd. none of the above
b. 8.4 x10^2 kg
When two substances react to form products, the reactant used up is called what?a. determining reagentb. limiting reagentc. excess reagentd. catalytic reagent
b. limiting reagent
What is decomposition?
breaking substances apart
Mercury can be obtained by reacting mercury(II) sulfide with calcium oxide. How many grams of calcium oxide are needed to produce 36.0 g of Hg?4HgS(s) + 4CaO(s) -->4Hg(l) + 3CaS(s) + CaSO4a. 1.80 gb. 7.56 gc. 10.1 gd. 13.4 g
c. 10.1 g
How many grams of beryllium are needed to produce 36.0 g of hydrogen? (Assume anexcess of water.) Be(s) + 2H2O(l) --> Be(OH)2 (aq) + H2(g)
c. 162 g
n a particular reaction between copper metal and silver nitrate, 12.7 g Cu produced 38.1 g Ag. What is the percent yield of silver in this reaction?Cu + 2AgNO3--> Cu(NO3) 2 + 2Ag
c. 88.2%
Lead nitrate can be decomposed by heating. What is the percent yield of the decomposition reaction if 9.9 g Pb(NO3 )2 are heated to give 5.5 g of PbO?2Pb(NO3 )2(s) -->2PbO(s) + 4NO2(g) + O2 (g)
d. 82%
Glucose, C6H12O6, is a good source of food energy. When it reacts with oxygen, carbon dioxide and water are formed.How many liters of CO2 are produced when 126 grams of glucose completely react with oxygen? C6H12O6 (s) + 6 O2 --> 6 CO2 (g) + 6 H2O (l) = 673 kcala. 4.21 Lb. 5.33 Lc. 15.7 Ld. 94.1 L
d. 94.1 L
The name of the information that you get from your experiment (you organize it into charts and graphs).
data
Atomic radius generally increases as we move __________.
down a group and from right to left across a period
Which subatomic particle has a negative charge?
electron
What are the 3 subatomic particles of an atom?
protons, neutrons, electrons
A series of steps used by scientists to solve a problem or answer a question.
scientific method
Chemical bonds form when atoms
share or transfer electrons
Where is the element's atomic NUMBER located?
the top
An ionic bond forms when atoms ___________ electrons.
transfer
Which area on the periodic table represents the electrons in the "d" sublevel?
transition elements
Is this equation balanced?
yes
Which of the following is not a correct designation for a sublevel?
zz