Answers FPS Conceptual Science BLab: Measuring pH

Cumulative Exam Answers

2 verified answers

Free Preview

Which compound contains both sigma and pi bonds?

HCCl3

H2CO

H2S

HBr

Free Preview

A beam of light passes though a liquid in a test tube without scattering. Which type of mixture is most likely in the test tube?

colloid

emulsion

solution

suspension

According to the collision theory, which is required for a high number of effective collisions?

a very low amount of force from colliding molecules

a very low amount of kinetic energy from colliding molecules

molecular collisions that have very specific orientations

molecular collisions with energy to overcome activation energy

Which diagram shows electrons violating the Pauli exclusion principle?

A box contains an up arrow.

A box contains an up and a down arrow.

A box contains an up and a down arrow.

A box contains an up and a down arrow.

When a drawing of a circle made in the center of a piece of paper with a black marker gets wet, the marker bleeds, and as the water moves through the paper the ink separates into several colors. What method of separation does this describe?

evaporation

distillation

filtration

chromatography

What is a common use of bases?

as a component of vinegar

as a component of car batteries

to make foods tart

to reduce indigestion

The table below gives the numbers of protons, electrons, and neutrons in four atoms.AtomNumber of protonsNumber of electronsNumber of neutrons1393952240405033939544404051Based on the information that is given, which atom in the table has the highest mass?

The reaction of a Lewis acid with a Lewis base would most likely be accompanied by an increase in which item?

covalent bonds

hydronium ions

electron pairs

hydroxide ions

Which of the following shows a Bronsted-Lowry acid reacting?

CO + NO2 CO2 + NO

NH3 + H+ NH4+

+ H+ HCO3–

HCl + H2O H3O+ + Cl–

Ca(OH)2 is added to a large beaker of water. How is the solution different from the original water?

The solution turns blue litmus to red.

The solution turns phenolphthalein pink.

The solution has more hydrogen ions.

The solution has fewer hydroxide ions.

Two cups of coffee, one that is at 10°C and one that is at 20°C, are mixed. Which statement about the temperature of the mixture is correct?

There is no kinetic energy transfer so the temperature of the coffee in the warmer cup is the final temperature.

The kinetic theory dictates that the temperature of the coffee in the cooler cup is the final temperature.

Energy is transferred from faster moving molecules to slower moving molecules, and the result is the average of 15°C.

Energy transfer occurs as the molecules collide, and the result is additive; the final temperature is 30°C.

Which best describes the function of a centrifuge?

to separate the solute from the solvent

to separate the dissolved part of a solution into layers

to separate a mixture by heating it for a long period of time

to separate the undissolved particles of a mixture into layers

In an experiment, a student wants to increase the rate of a reaction that involves gases. Which change to the reactants would accomplish this?

Increase the volume to decrease pressure and to increase concentration.

Increase the volume to increase pressure and to decrease concentration.

Decrease the volume to decrease pressure and to increase concentration.

Decrease the volume to increase pressure and to increase concentration.

An element has five valence electrons available for bonding. This element is most likely which of the following?

boron

phosphorus

tin

tellurium

Which best describes a compound such as magnesium oxide?

an impure substance that is made up of two elements

a mixture of two uncommon substances

a mixture of two common elements

a pure substance that is made up of different elements

In which orbitals would the valence electrons for carbon (C) be placed?

s orbital and d orbitals

s orbital only

p orbitals only

s orbital and p orbitals

A single atom of an element has 21 neutrons, 20 electrons, and 20 protons. Which element is it?

Pure water at 25°C

ionizes in the presence of acid to form an equilibrium in which

self-ionizes to form an equilibrium in which

Which statement is true about crystal lattice energy?

It increases as the size of the ions increases.

It increases as the charge on the ions decreases.

It is the energy that ions absorb when they form a crystal.

It is a measure of the strength of the bonds between ions.

Consider the following intermediate chemical equations.What is the enthalpy of the overall chemical reaction ?

-999 kJ

-250. kJ

250. kJ

999 kJ

The pOH of a solution is 6.0. Which statement is correct?Use and .

The pH of the solution is 20.0.

The concentration of OH– ions is .

The pH of the solution is 8.0.

Which is the first step in the dissolving process?

The solute becomes like the solvent.

The solute molecules are carried into the solution.

The solvent molecules surround the solute particles.

The solvent molecules are attracted to particles at the surface of the solute.

Which of the following best describes a pair of elements that will form an ionic bond?

C and H: Hydrogen easily loses electrons, and carbon gains them.

Li and O: Oxygen easily loses electrons, and lithium gains them.

P and Cl: Phosphorus easily loses electrons, and chlorine gains them.

Ca and Br: Calcium easily loses electrons, and bromine gains them.

Water is dissolved into n-butanol (a polar liquid). Which is the second step at the molecular level as water dissolves into n-butanol?

n-Butanol mixes with water.

Water molecules are carried into n-butanol.

n-Butanol molecules surround water molecules.

n-Butanol molecules are attracted to the surface of the water molecules.

Which is true of transition metals when moving from left to right on the periodic table?

The d sublevels are not filled across the period.

The cation radii become larger across the period.

Atomic radii increase slightly and then start to decrease.

Atomic radii decrease slightly and then start to increase.

A solar panel combines multiple photovoltaic cells. Which type of energy is used to power a solar panel?

kinetic energy

thermal energy

electromagnetic energy

gravitational potential energy

The properties of two elements are listed below.ElementAtomic radius(pm)Ionic radius(pm)First ionization energy(kJ/mol)Electron affinity(kJ/mol)ElectronegativityBr1141951140–3253.0K243152.2418.8–48.40.82Which prediction is supported by the information in the table?

K will give up an electron more easily than Br.

Both K and Br will have the same pull on electrons.

K will have a smaller size in comparison to Br.

Both K and Br will produce ions of the same size.

The main component of smog is . Smog is a product that is formed through the following series of intermediate chemical reactions.What is the overall chemical equation for smog after the above intermediate reactions are combined?

Upper N subscript 2 (g) plus 3 upper O subscript 2 (g) plus 2 upper O subscript 3 (g) plus 2 upper O (g) right arrow 8 upper N upper O (g) plus 4 upper N upper 0 subscript 2 (g) plus 2 upper O subscript 3 (g).

Upper N subscript 2 (g) plus 3 upper O subscript 2 (g) plus upper O subscript 3 (g) plus upper O (g) right arrow 9 upper N upper O (g) plus 3 upper N upper 0 subscript 2 (g) plus 2 upper O subscript 3 (g).

Upper N subscript 2 (g) plus 3 upper O subscript 2 (g) right arrow 3 upper N upper O subscript 2 (g).

Upper N subscript 2 (g) plus 2 upper O subscript 2 (g) right arrow 2 upper N upper O subscript 2 (g).

A sample of propane (C3H8) has a mass of 0.47 g. The sample is burned in a bomb calorimeter that has a mass of 1.350 kg and a specific heat of 5.82 J/(g • °C). How much energy is released by the reaction if the temperature of the calorimeter rises by 2.87°C?Use .

7.85 kJ

10.6 kJ

22.5 kJ

47.9 kJ

The enthalpy of formation of water is –285.8 kJ/mol. What can be inferred from this statement?

The enthalpy of the products is equal to the enthalpy of the reactants.

Heat is absorbed during the process.

Heat is released during the process.

The enthalpy of the products is more than the enthalpy of the reactants.

How does heat differ from temperature?

Temperature is the measure of heat.

Temperature and heat are the same thing.

Temperature measures thermal energy, and heat is the flow of thermal energy.

Temperature measures the loss of energy, and heat measures the gain of energy.

A sample of an unknown substance has a mass of 0.158 kg. If 2,510.0 J of heat is required to heat the substance from 32.0°C to 61.0°C, what is the specific heat of the substance?Use .

0.171 J/(gi°C)

0.548 J/(gi°C)

15.9 J/(gi°C)

86.6 J/(gi°C)

During photosynthesis, sunlight shining on a plant is absorbed. Through several chemical reactions, the plant produces sugar, a high-energy compound, from simpler substances. What energy transformation occurs during this process?

thermal energy to chemical energy

electromagnetic energy to chemical energy

kinetic energy to potential energy

potential energy to chemical energy

What is the element Ar classified as in the periodic table?

a noble gas

a halogen

a metalloid

a metal

Ethyne (C2 H2 (g), Hf = 226.77 kJ/mol) undergoes complete combustion in the presence of oxygen to produce carbon dioxide (CO2 (g), Hf = –393.5 kJ/mol ) and water (H2 O(g), Hf = –241.82 kJ/mol) according to the equation below.What is the enthalpy of combustion (per mole) of C2 H2 (g)? Use .

–2511.2 kJ/mol

–1255.6 kJ/mol

–862.1 kJ/mol

–431.0 kJ/mol

Which element would most likely have chemical properties similar to that of fluorine (F)?

The diagram below shows that the periodic table is divided into different blocks.Elements that have complete valence electron shells are mostly found in the

s block.

d block.

p block.

f block.

Which refers to the amount of a solute that will dissolve in a given volume of solvent at a given temperature and pressure?

solubility

supersaturated

dissolution rate

concentrated

Which units express specific heat capacity?

J/°C, J/K, cal/°C, cal/K

J/(gi°C), J/(giK), cal/(gi°C), cal/(giK)

J, cal

°C, K

Sulfur reacts with oxygen to form sulfur dioxide (SO2(g), Hf = –296.8 kJ/mol) according to the equation below.What is the enthalpy change for the reaction? Use .

–593.6 kJ

–296.8 kJ

296.8 kJ

593.6 kJ

Two different gases are stored in separate closed containers. If both gases have a temperature of 50°C, which statement is true?

The thermal energies of gas molecules in the two containers are unrelated.

The gas molecules in both containers will absorb heat from the surroundings.

The molecules in one gas will transfer energy to the molecules in the other gas.

The gas molecules in both containers have the same average kinetic energy.

Which scientist established the law of octaves?

Antoine Lavoisier

Dmitri Mendeleev

Henry Moseley

John Newlands

What is the definition of a Lewis acid?

a substance that accepts electrons to form a covalent bond

a substance that donates electrons to form a covalent bond

a substance that accepts a proton

a substance that donates a proton

The table lists the lattice energies of some compounds.CompoundLattice Energy (kJ/mol)LiF –1,036LiCl –853NaF –923KF –821NaCl –786Which statement about crystal lattice energy is best supported by the information in the table?

The lattice energy increases as cations get smaller, as shown by LiF and KF.

The lattice energy increases as the cations get larger, as shown by LiF and LiCl.

The lattice energy decreases as cations get smaller, as shown by NaCl and NaF.

The lattice energy decreases as the cations get smaller, as shown by NaF and KF.

Selected properties of antimony (Sb) and iodine (I) are listed in the table below.ElementAtomic radius(pm)First ionization energy(kJ/mol)Electron affinity(kJ/mol)ElectronegativitySb145?–1032.05I1401008–295?Which predictions can most likely be made?

Sb has a lower ionization energy but a higher electronegativity than I.

Sb has a higher ionization energy but a lower electronegativity than I.

Sb has a lower ionization energy and a lower electronegativity than I.

Sb has a higher ionization energy and a higher electronegativity than I.

Which statement is true about ionic compounds?

They are made up of many large molecules that are bonded together.

They are made up of atoms of only one type of element.

They are made up of particles that are arranged in a repeating pattern.

They are made up of a random ratio of elements that are bonded together.

Which of the following can easily form an ionic bond with a cation?

NH4+

PO43–

How can the pH of a solution be calculated if the pOH is known?

by taking the negative logarithm of pOH

by adding the pOH to 14

by raising 10 to the power of –pOH

by subtracting the pOH from 14

Which element is classified as a noble gas?

Iron reacts with oxygen in a chemical hand-warmer. How should this reaction be categorized?

as an exothermic process because it releases heat

as an endothermic process because it releases heat

as an exothermic process because it absorbs heat

as an endothermic process because it absorbs heat

Did you find these answers helpful?

Cumulative Exam Answers

More from this Course

TRY EDGENUITY HACKS