Fall FINAL test questions
Which element has both metallic and nonmetallic properties?
Si
Which of these reactions is possible?
Sn + H₂SO₄ ==> SnSO₄ + H₂
What is the balanced equation for: ___ SnO₂ + ___ H₂ -------> ___ Sn + ___ H₂O?
SnO₂ + 2 H₂--> Sn + 2H₂O
What determines the order of placement of the elements on the modern Periodic Table?
atomic number
What is the temperature of absolute zero measured in C?
-273C
A compound differs from a mixture in that a compound always has a
homogeneous composition
The chemical name of FeCl2 is:
iron (II) chloride
In a chemical reaction, the mass of the products ____.
is equal to the mass of the reactants
Which two products are formed when magnesium reacts with hydrochloric acid?
magnesium chloride and hydrogen
The chemical name of Mg₃(PO₄)₂ is:
magnesium phosphate
In every chemical reaction, ____.
mass and atoms are conserved
An atom of carbon-12 and an atom of carbon-14 differ in
mass number
What is the metric system prefix for the quantity 0.000 001?
micro-
Which gas is monatomic at standard room conditions?
neon (When an energy shell is completely filled,It is inert or nonreactive)
An atom is electrically neutral because the
number of protons equals the number of electrons.
In a combustion reaction, one of the reactants is:
oxygen
Which elements belong in the same family or group?
sodium and potassium
The alkali metals lithium, potassium and sodium all react with cold water to produce agas and an alkaline solution. What is their order of increasing reactivity?
sodium, potassium , lithium
When a precipitation reaction occurs, the ions that do not form the precipitate
stay dissolved in solution.
Chlorine boils at 239 K. What is the boiling point of chlorine expressed in degrees Celsius?
-34C
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)
0.20 mol
How many moles of aluminum are needed to react completely with 1.2 mol of FeO? 2Al(s) + 3FeO(s) → 3Fe(s) + Al₂O₃(s)
0.8 mol
What is the net charge on an ion that has 9 protons, 11 neutrons, and 10 electrons?
1-
What is the volume of 80.0 g of ether if the density of ether is 0.70 g/mL?
1.1 X 10^2
What is the charge on the cadmium ion in this compound?: Cd(MnO₄)₂
2+
What is the volume of a salt crystal measuring 2.44 X 10 (^-2) m by 1.4 X 10 (^-3) m by 8.4 X 10(^-3) m?
2.9 X 10 (^-7) m (^3)
What is the percent composition of chromium in BaCrO₄?
20.5%
What is the total number of atoms represented in the formula CuSO4 . 5H2O?
21
Hydrogen gas can be produced by reacting aluminum with sulfuric acid. How many moles of sulfuric acid are needed to completely react with 15.0 mol of aluminum?2Al(s) + 3H₂SO₄(aq) → Al₄(SO₄)₃(aq) + 3H₂(g)
22.5 mol
What is the temperature -34C expressed in kelvins?
239 K
A 100.00-gram sample of naturally occurring boron contains 19.78 grams of boron-10 (atomic mass = 10.01 atomic mass units) and 80.22 grams of boron-11 (atomic mass = 11.01 atomic mass units). Which numerical setup can be used to determine the atomic mass of naturally occurring boron?
(0.1978)(10.01) + (0.8022)(11.01)
Element X has two isotopes. If 72.0% of the element has an isotopic mass of 84.9 atomic mass units, and 28.0% of the element has an isotopic mass of 87.0 atomic mass units, the average atomic mass of element X is numerically equal to
(72.0 × 84.9)/100 + (28.0 × 87.0)/100
What is the total charge of the nucleus of a carbon atom?
+6
How many moles of glucose, C₆H₁₂O₂, can be "burned" biologically when 10.0 mol of oxygen is available?C₆H₁₂O₂(s) + 6O₂(g) → 6CO₂(g) + 6H₂O(l)
1.67 mol
When iron rusts in air, iron(III) oxide is produced. How many moles of oxygen react with 2.4 mol of iron in the rusting reaction?4Fe(s) + 3O₂(g) → 2Fe2O₃(s)
1.8 mol
If the temperature changes by 100 K, by how much does it change in Celcius?
100C
Express the product of 2.2 mm and 5.00 mm using the correct number of significant digits.
11 mm^2
What is the measurement 111.009 mm rounded off to four significant digits?
111.0 mm
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?
127 g
How many grams of beryllium are needed to produce 36.0 g of hydrogen?
162 g
In the reaction 2CO(g) + O₂(g) → 2CO₂(g), what is the ratio of moles of oxygen used to moles of CO₂ produced?
1:2
What is the total number of carbon atoms in ethanoic (acetic) acid, (also known as vinegar), with a molecular formula CH₃COOH?
2
Which expression represents the percent by mass of nitrogen in NH₄NO₃?
28 g N/80 g NH₄NO₃ 100%
In the measurement 0.503 L, which digit is the estimated digit?
3
Express the product of 4.0 10(-^2)m and 8.1 10(^2)m using the correct number of significant digits.
3.2 10(^1)
What is the balanced equation for: __ KOH + __ H₃PO₄ --> __ K₃PO₄ + __ H₂O
3KOH + H₃PO₄ --->K₃PO₄ + 3 H₂O
The expression of 5008 km in scientific notation is ____.
5.008 10^3 km
When the number 602,000,000,000,000,000,000,000 is written in scientific notation, it is
6.02 E23
What is the maximum number of grams of PH₃ that can be formed when 6.2 g of phosphorus reacts with 4.0 g of hydrogen to form PH₃?
6.8 g
What is the mass number of an atom which contains 28 protons, 28 electrons, and 34 neutrons?
62
What is the percent by mass of carbon in acetone, C₃H₆O?
62.1%
If 60.2 grams of Hg combines completely with 24.0 grams of Br to form a compound, what is the percent composition of Hg in the compound?
71.5%
Lead nitrate can be decomposed by heating. What is the percent yield of the decomposition reaction if 9.9 g Pb(N₃O)₂ are heated to give 5.5 g of PbO?
82%
What is the percent composition of carbon, in heptane, C₇H₁₆?
84%
In 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?
88.2%
The nucleus of 20 X element has 11
9 neutrons
A displacement reaction can be described as:
A more reactive metal replacing a less reactive metal in its compound.
What was concluded about the structure of the atom as the result of the gold foil experiment?
A positively charged nucleus is surrounded by mostly empty space.
how do you read a buret?
Burets need to be read from the top down.
What is the formula for carbon tetrachloride?
CCl₄
What is the formula for carbon dioxide?
CO2
Plaster of Paris, drywall, and the mineral gypsum are all calcium sulfate. What is the formula of calcium sulfate?
CaSO₄
What is the formula for chromium (III) phosphate?
CrPO₄
Which of the following is NOT an empirical formula?
C₂N₂H₈
Which of the following compounds have the same empirical formula?
C₇H₁₄ and C₁₀H₂₀
In naming acids, what is the first question you should ask yourself?
Does the anion have oxygen?
Which of these is NOT a reason reactions go forward and create more product?
Formation of a liquid.
Which of the following net ionic equations best represents the reaction that takes place in aqueous solution, when sulfuric acid and sodium hydroxide solutions are mixed?
H+ + OH- --> H2O
Why doesn't gold tarnish in air?
It is relatively unreactive.
What is the formula of nitrogen triiodide?:
NI3
It is important to be able to recognize the ions in an ionic compound. The name of the ionic compound gives you this information. What are the ions in sodium chloride?
Na+, Cl-
The correct formula for sodium chloride (table salt) is:
NaCl
According to the solubility rules, which one of the following is soluble in water?
Na₂S
The formula for dinitrogen pentaoxide is:
N₂O₅
Which symbols represent atoms that are isotopes?
O-16 and O-18, Isotopes are atoms of the same element (same atomic number) but with a different number of neutrons (different atomic mass)
Which atom contains exactly 15 protons?
P-32
Which of the following is NOT true about "yield"?
The actual yield may be different from the theoretical yield because insufficient limiting reagent was used.
Which of the following is NOT true about empirical and molecular formulas?
The empirical formula of a compound can be triple its molecular formula.
What is the information on the activity series used for?
To determine whether or not a single-replacement reaction will occur.
Matter that is composed of two or more different elements chemically combined in a fixed proprotion is classified as
a compound
Which is an example of a chemical change?
a nail rusting
The closeness of a measurement to its true value is a measure of its ____.
accuracy
Which of the following substances can be decomposed (broken down) by chemical means?
ammonia, NH3
Which compound is soluble: magnesium hydroxide or ammonium hydroxide?
ammonium hydroxide
Which compound is soluble?
ammonium phosphate
Which of these rules NEVER apply in naming acids without oxygen?
an 'ous' ending (All acids without oxygen are easily named. They all start with the prefix 'hydro' and end with 'ic" and have the root of the anion in between. Examples are:HF = hydrofluoric acidH2S = hydrosulfuric acidThese types of acid never end in 'ous')
A proton has a charge that is opposite the charge of
an electron
how do you read a graduated cylinder?
bottom to top
The chemical name of Cd(MnO₄)₂:
cadmium permanganate
Which of the following is NOT a reason why actual yield is less than theoretical yield?
conservation of mass
P₂O₅ is named:
diphosphorus pentaoxide
The lowest whole-number ratio of the elements in a compound is called the ____.
empirical formula
How many significant figures are in the measurement 811.40 grams?
five
What information is needed to calculate the percent composition of a compound?
the formula of the compound and the atomic mass of its elements
A balanced chemical equation has
the same number of each kind of atom on both sides of the equation.
When an equation is used to calculate the amount of product that will form during a reaction, then the value obtained is called the ____.
theoretical yield
How many significant figures are in the measurement 40,500 mg?
three
Which products always are created in a combustion reaction?
water and carbon dioxide
The atomic mass of titanium is 47.88 atomic mass units. This atomic mass represents the
weighted average mass of all the naturally occurring isotopes of Ti
Which compound is insoluble: potassium carbonate or zinc carbonate?
zinc carbonate