2016 Chemistry Sol

Front 1

A student measures the mass of 1.00 g aluminum rod as 0.99 g. The best estimate of the percent error associated with this measurement is:

Back 1

1%

Front 2

The most efficient way to determine whether a reaction is an exothermic chemical reaction is to use:

Back 2

A temperature probe

Front 3

2Al(C2H3O2)3+3BaSO4→Al2(SO4)3+3Ba(C2H3O2)2Which type of chemical reaction does this equation represent?

Back 3

Double replacement

Front 4

What is the oxidation number of an oxide ion?

Back 4

-2 or 2-*

Front 5

What is the molarity of a solution with 0.2 moles of potassium permanganate (KMnO4) dissolved in enough water to make a 500.0 mL solution?

Back 5

0.4 M

Front 6

When 92.0 g of ethanol (C2H5OH) are vaporized at its boiling point of 78.3°C, it requires 78.6 kJ of energy. What is the approximate molar heat of vaporization of ethanol in kJ/mol?

Back 6

39.3

Front 7

What is the density of an aqueous solution that has a mass of 10.081 g and 12.5 mL?

Back 7

0.806 or .806*

Front 8

Which element has 16 neutrons, 15 protons, and 15 electrons?

Back 8

Phosphorus (P)

Front 9

Al(s)+3AgNO3(aq)→Al(NO3)3(aq)+3Ag(s)This equation represents which type of chemical reaction?

Back 9

Single-replacement

Front 10

In the formula for barium chloride, (BaCl2), barium (Ba) is written first because it is:

Back 10

The positive ion

Front 11

Which of these laboratory techniques is best to separate a solid from a liquid to recover the liquid?

Back 11

Filtering

Front 12

Which of these is NOT required to ensure that stock solutions are free of contamination?

Back 12

Store all solutions in brown bottles

Front 13

Which of these values is most responsible for changing the boiling and freezing points of a solvent?

Back 13

Number of the solute particles

Front 14

What is the name of the compound with the formula NH4NO3?

Back 14

Ammonium nitrate

Front 15

Calculate the number of moles of Li3PO4 in 2.2L of a 0.60 M Li3PO4 solution.

Back 15

1.3

Front 16

N2(g)+3F2(g)⇄2NF3(g)Equilibrium has been reached for the reaction shown. Which conclusion is correct?

Back 16

The particle pressures of N2, F2, and NF3 will stay constant

Front 17

If 89.6 joules of heat are needed to heat 20.0 grams of iron from 30.0°C to 40.0°C, what is the specific heat of the iron in J/g.°C?

Back 17

0.448

Front 18

Which of the four substances on this pH scale is slightly basic?

Back 18

Human blood

Front 19

Which element will most likely form covalent bonds with fluorine?

Back 19

Carbon

Front 20

The physical process of evaporation involves:

Back 20

Overcoming intermolecular forces

Front 21

__C2H4+ ? O2→__CO2+__H2OHow many moles of O2 are in the chemical equation when balanced using the lowest whole numbers?

Back 21

3

Front 22

While English physicist J.J. Thompson was carrying out experiments on cathode rays, he was able to determine that the rays consisted of particles he called “corpuscles.” These particles were later named:

Back 22

Electrons

Front 23

In the Haber process, nitrogen (N2) and hydrogen (H2) are directly combined to form ammonia (NH3). Which illustration contains the stoichiometric quantities of the reactants for this reaction?

Back 23

Front 24

A beaker of water is placed in a large sealed jar that is attached to a vacuum pump. As air is pumped out of the jar, the water begins to boil because:

Back 24

The air pressure in the jar has been lowered until it is equal to the vapor pressure of the water

Front 25

According to the periodic table of elements, which elements belong to the same period?

Back 25

Germanium, Arsenic, Gallium

Front 26

How many moles are in 2.04x1024 molecules of H2O?

Back 26

3.39 mol

Front 27

What is the name for FeCl3, using the IUPAC nomenclature rules?

Back 27

Iron (III) Chloride

Front 28

An expandable container of oxygen gas has a volume of 125 mL at a temperature of 25.0°C. What volume will the gas occupy at 55.0°C?

Back 28

138 mL

Front 29

Which of these correctly describes how organic catalysts operate in biological reactions?

Back 29

They lower the activation energy of the reactions

Front 30

What volume will 35.9 g of hydrogen gas (H2) occupy at STP?

Back 30

399 L

Front 31

__Ca(NO3)2+ ? H3PO4→__Ca3(PO4)2+__HNO3When this equation is balanced, the coefficient in front of H3PO4 is:

Back 31

2

Front 32

Increasing the volume of a sealed container will cause the gas particles within the container to:

Back 32

Exhibit lower pressure

Front 33

Each of four groups of students determined and recorded the melting point of a solid compound. If the actual melting point is 113°C, which group had the best precision?

Back 33

Group 4

Front 34

Consider any set of three adjacent elements in the same period on the periodic table. For which characteristic is the average for the three elements always equal to the value of the middle element?

Back 34

Atomic number

Front 35

A substance has a molecular formula of C8H10N4O2. The empirical formula is:

Back 35

C4H5N2O

Front 36

Create the formula for diboron trioxide using the symbols provided.

Back 36

B2O3

Front 37

What is the name for the compound AlI3?

Back 37

Aluminum iodide

Front 38

2C4H10+13O2→8CO2+10H2OHow many moles of carbon dioxide (CO2) are produced when reacting 6.00 moles of butane (C4H10) in excess oxygen (O2)?

Back 38

24.0 mol

Front 39

Which structure represents a nonpolar molecule?

Back 39

Front 40

Using only one trial to collect data in an experiment:

Back 40

Causes the conclusion to be less reliable

Front 41

A common product of acid-base neutralization reactions is:

Back 41

Water

Front 42

Based on the information provided, which solution is a base and a weak electrolyte?

Back 42

CH3NH2

Front 43

What is the half-life of Americium-242?

Back 43

16 hours

Front 44

Two electrons are shared equally in Bromine (Br2). What type of bond is represented between the bromine atoms in the Lewis structure?

Back 44

Nonpolar covalent bond

Front 45

A student is studying the effects of several solutions on the prevention of the browning of apples. The student used solutions having different pH values and immersed three apple slices in equal volumes of each of the solutions. Which of these is the independent variable in this investigation?

Back 45

pH of a solution

Front 46

An experiment produced 0.10 g CO2 with a volume of 0.056 L at STP. If the accepted density of CO2 at STP is 1.96 g/L, what is the approximate percent error?

Back 46

8.2%