Chemistry Final

The oxidation state of chlorine is ClO- is

+1

Express the number 0.0810 in scientific notation

8.10 x 10^-2

When solutions of carbonic acid and copper (II) hydroxide react, which of the following are spectator ions?

None

Which of the following salts is insoluble in water?

None

Balanced chemical equations imply which of the following?

Number of atoms are conserved in chemical change

We generally report a measurement by recording all of the certain digits plus ____ uncertain digit(s).

One

Which best represents a gaseous compound?

Option C

Which best represents a heterogenous mixture of two elements?

Option D

A component of the solution in minority is known as the

Solute

The oxidation state of iodine is IO3- is

+5

The average mass of a carbon atom is 12.011. Assuming you were only able to pick up one carbon unit, the chances you would randomly get one with a mass of 12.011 is

0%

A scientist obtains the number 0.045006700 on a calculator. If this number actually has four (4) significant figures, how should it be written?

0.04501

You measure water in two containers: a 10-mL graduated cylinder with marks at every mL, and a 1-mL pipet marked at every 0.1 mL. If you have some water in each of the containers and add them together, to what decimal place could you report the total volume of water?

0.1 mL

Manganese makes up 1.3x10^-4 percent by mass of the elements found in a normal healthy body. How many grams of manganese would be found in the body of a person weighing 206lb?

0.12g

Which of the following metric relationships is incorrect?

1 gram = 10^3 kilograms

_PCl5 + _H2O ---> _POCl3 + _HCl

1, 1, 1, 2

Convert 0.0494ft^3 to L. (2.54cm = 1in, 1L = 1 dm^3)

1.40 L

Suppose that you purchased a water bed with the dimensions 2.55m x 2.53dm x 235 cm. What mass of water does this bed contain?

1.52 x 10^6 g

A monolayer containing 3.23x10^-6 of oleic acid has an area of 20.ocm^2. The density of oleic acid is 0.895g/mL. What is the thickness of the monolayer?

1.80x10^-7

What is the best answer to report for (3.478gx1.164g/2.00mL) - 0.169 g/mL

1.85 g/mL

A 230 mL sample of 0.275 M solution is left on a hot plate overnight; the following morning the solution is 1.29 M. What volume of the solvent has evaporated from the 0.275M solution?

181.0 mL

What volume of 18 M sulfuric acid must be used to prepare 2.30 L of 0.145M H2SO4?

19 mL

The number of protons, neutrons and electrons in K+ are

19 p, 20n, 18e

A given sample of xenon fluoride compound contains molecules of a single type XeFn, where n is some whole number. Given that 8.06x10^20 molecules of XeFn weighs 0.227g, find n.

2

An unknown diprotic acid requires 44.39 mL of 0.111 M NaOH to completely neutralize a 0.580-g sample. Calculate the approximate molar mass of the acid.

235 g/mol

Which of the following is incorrectly named?

NO3-, nitrite ion

Which best represents a homogenous mixture of an element and a compound

Option E

A component of a solution in majority is known as the

Solvent

The reactant which, when used up completely, can produce the least amount of product, is the limiting reactant

True

All of the following are in aqueous solution. Which is incorrectly named?

HBr, bromic acid

Which of the following is a strong acid?

HClO4

The combined average atomic masses of one mole of a compound is known as the molar mass of that substance

True

The reactant with the highest molar mass is always the limiting reactant.

True

the agreement of a particular value with the true value

accuracy

Rutherford's experiment was important because it showed that

an atom is mostly empty space

The amount of uncertainty in a measured quantity is determined by

both the skill of the observer and the limitations of the measuring instrument

As part of the calibration of a new laboratory balance, a 1.000-g mass is weighed with the following results: Trial Mass 1 1.201+-0.001 2 1.202+-0.001 3 1.200+-0.001 The Balance is: a. Accurate but imprecise b. Both inaccurate and imprecise c. Precise but inaccurate d. Accuracy and precision are impossible to determine with available information e. Both accurate and precise

c. precise but inaccurate

The limiting react in a reaction

is the reaction for which you have the fewest number of moles

The chemical counting in the SI is known as the

mole

Which of the following is not a strong base?

NH3

A hypothetical element consists of two isotopes of masses 69.95amu and 71.95amu with abundances of 25.7% and 74.3% respectively. What is the average atomic mass of the element?

71.4 amu

Given the equation 3A + B --> C + D, you react 2 moles of A with one mole of B. Which of the following is true?

A is the limiting reactant because you need three moles of A and have 2

You take an aspirin tablet (a compound solely consisting of C, H, and O) with a mass of 1.00g, burn it in the air, and 2.20g of CO2 and 0.400g H2O. The molar mass of aspirin is between 170 and 190 g/mol. The MF is ...

C9H8O4

A hydrocarbon is found to be 85.6% carbon by mass. What is the EF?

CH4

Which of the following ions is most likely to form an insoluble sulfate?

Ca2+

Which of the following aqueous solutions contains the greatest number of ions?

300.0mL of 0.10 M CaCl2

Bromine exists naturally as a mixture of bromine-79 and bromine-81 isotopes. An atom of bromine-79 contains

35 protons, 44 neutrons, 35 electrons

When 87.7 is added to 73.841, the result should be reported with ___ significant figures. And when 87.7 is divided by 73.841 the result should be reported with ___significant figures. a. 3,5 b. 4,4 c. 4,3 d. 3,3

4,3

What is the mass of 4 atom(s) of copper in grams?

4.22x10^-22

What mass of NaOH is required to react exactly with 25.0mL of 2.7 M H2SO4?

5.4g

How many grams of NaCl are contained in 350. mL of a 0.287 M solution of sodium chloride?

5.87 g

What is the numeric equivalent of one mole?

6.022x10^23

6.1 seconds contain this many picoseconds

6.1x10^12

A wavelength of red light is measured at 655nm. What is the measurement in cm?

6.55x10^-5

Hydrocortisone valerate is an ingredient in hydrocortisone cream, prescribed for skin problems. Its MF is C26H38O6. What percent by mass of carbon in hydrocortisone valerate?

69.9%

Which of the following statements from Dalton's atomic theory is no longer true, according to the modern atomic theory?

All of the statements are true

If the Thomson model of the atom had been correct, Rutherford would have observed:

Alpha particles going through the foil with little to no deflection

The sum total of the representative masses of the products between the masses of the most stable isotopes and the decimal equivalent of the relative abundance is known as:

Average atomic mass

A number equivalent to the number of atoms in 12 grams of carbon-12 is known as

Avogadro's number

Which of the following pairs is incorrect?

BaPO4, barium phosphate

An ion is formed

By either adding or subtracting electrons from the atom

In balancing an equation, we change the ____ to make the number of atoms on each side of the equation to balance

Coefficients

Aqueous solutions of sodium sulfide and copper (II) chloride are mixed together. Which statement is correct?

CuS will precipitate from solution

Which separation technique is based on differences in the volatility of the substances to be separated?

Distillation

In which of the following does nitrogen have an oxidation state of +4?

NO2

The smallest whole number ratio of moles of the elements compromising a compound is known as

Empirical Formula

A chemical that changes color at the endpoint of a reaction is called a colorimeter

False

An acid is a substance that produces OH- ions in water

False

One can always do a direct conversion from mass of a substance to particles as long as you express your answer to the correct number of sig figs

False

Oxidation is the gain of electrons

False

The concentration of salt water solution that sits in an open beaker decreases over time

False

When balancing a chemical equation, it is generally best to start with the least complicated molecules

False

Which of the following represent a set of isotopes? Atomic nuclei containing

I, IV and II, IV

When an integer is multiplied by the EF, its results in the total actual amount of the atoms in the substance. This is known as the

Molecular Formula

Which of the following pairs of compounds can be used to illustrate the law of multiple proportions?

NO and NO2

Many classic experiments have given us indirect evidence of the nature of the atom. Which of the experiments listed below did NOT give the results described? a. The Rutherford experiment proved the Thomson "plum-pudding" model of the atom to be essentially correct b. All of the above experiments gave the results described c. Millikan's oil-drop experiment showed that the charge on any particle was a simple multiple of the charge on the electron d. The electric discharge tube proved that electrons have a negative charge e. The Rutherford experiment was useful in determining the nuclear charge on the atom

The Rutherford experiment proved the Thomson "plum-pudding model" of the atom to be essentially correct

A reducing agent is an electron donor

True

Polar molecules always have an unequal distribution of charge within the molecule

True

The molecular formula always represents the total number of atoms of each element present in a compound

True

Suppose you are given the percent by mass of the elements in a compound and you wish to determine the EF. Which of the following is true?

You must convert percent by mass ro relative numbers of atoms

In the reaction Zn + H2SO4 --> ZnSO4 + H2, which, if any, element is oxidized?

Zinc

Order the four metric prefixes from smallest to largest

nano- < milli- < centi- < kilo-