chemistry homework questions and answers

In the following reaction, which element is the limiting reactant?

2Fe(s) + 3Cl2(g) -> 2FeCl3(s) 

• iron
• chlorine
• neither
• both
• Cannot be determined without the original starting mass of both reactants. 

Ammonia gas is synthesized according to the balanced equation:

N2 (g) + 3H2 (g) →2NH3

If 15.0 liters of nitrogen are reacted with an excess of hydrogen, how many liters of ammonia could be produced? All gases are at STP.

• 45.1 L
• 20.0 L
• 30.0 L
• 10.0 L

Use Boyle's Law to find the final volume with the given conditions:

P1=600 mmHg

V1=200 mL

P2=780 mmHg

• 275 mL
• 354 mL
• 212 mL
• 154 mL

What type of reaction is a neutralization reaction?

• Decomposition
• Double replacement
• Synthesis
• Single replacement

Use Avogadro's Law to solve this problem. A 6.0 L sample of gas is known to contain 0.965 moles. If the amount of gas is increased to 1.80 moles, what is the new volume?

• 22.1 L
• 11.2 L
• 20.8 L
• 13.5 L

Percent yield is the quantity of product actually produced compared with the quantity ____.

• that should be produced
• of the excess reactant
• of the limiting reactant
• of actual amount produced

When an equation is used to calculate the amount of product that will form during a reaction, the value obtained is called the ____?

• percent composition
• percent yield
• theoretical yield 
• actual yield

Energy in the amount of 420 J is added to a 35 g sample of water at a temperature of 10°C. What is the final temperature of the water?

• 23 °C
• 14 °C
• 13 °C
• 20 °C

Provide the formula for calculating density.

• Density = Area/Mass
• Density = Mass x Volume
• Density = Mass/Volume
• Density = Mass x 2 x Volume

Which phase change occurs when a gas changed into a solid?

• Deposition
• Vaporization
• Sublimation
• Condensation

What do the colligative properties depend upon?

• The number of particles dissolved in a given mass of solvent
• None of the answer choices
• The nature of the solvent
• The nature of the solute

What is the difference between Charles's Law and the Gay-Lussac Law?

• Charles made his observations using a rigid container
• Charles's Law is more accurate
• The equations are different for each law
• Gay-Lussac made his observations using a rigid container

Which term is described as the percent by mass of any element in a compound?

• molecular formula
• empirical formula
• hydrate
• percent composition

The pressure of a mixture of nitrogen, carbon dioxide, and oxygen is 150 kPa. What is the partial pressure of oxygen if the partial pressure of the nitrogen and carbon dioxide are 100 kPa and 24 kPa?

• 20 kPa
• 26 kPa
• 29 kPa
• 35 kPa

Which answer choice describes the transfer of heat from a system to the surroundings?

• Heterogeneous
• Homogeneous
• Endothermic
• Exothermic

Which of the following answer choices has the larger atomic radius?

• Calcium
• Lithium
• Oxygen
• Fluorine

 Which of the following terms describes the point in a titration where the indicator changes color?

• Titrant
• Stopcock
• pink point
• Equivalence point

Who was the first person in history credited with the idea of the atom?

• Albert Einstein
• Democritus
• John Dalton
• J.J. Thomson

What happens when a chlorine atoms gains an electron?

• The ion has a -1 charge
• The ion becomes an anion
• A chloride ion is formed
• All of the answer choices

A mass of 2.50 g of hydrated copper (II) sulfate is placed in a crucible and heated. On heating, 1.59 g of white anhydrous copper (II) sulfate is left behind. Determine the percentage of water in copper (II) sulfate.

• 36%
• 64%
• 14%
• 23%

Pure water is a neutral substance. What is the pH of pure water?

• Five
• Seven
• Six
• Four

Who arranged the periodic table according to atomic mass?

• Dmitri Mendeleev
• Henry Moseley
• John Dalton
• Ernest Rutherford

 How many electrons can fit on the third energy level?

• Thirty-two
• Eighteen
• Two
• Eight

As you squeeze a balloon the pressure inside of the balloon increases. What gas law explains the observation?

• Combined Gas Law
• Boyles Law
• Avogadro's Law
• Charles's Law

Which of the following is the correct electron configuration for fluorine?

• 1s22s22p3
• 1s22s22p5
• 1s22s23p5
• 1s22s22p7

Copper is one of a group of metals called the coinage metals. How many atoms of copper (Cu) are in a pure copper coin weighing 12.0 g?

• 1.13 x 1023 atoms
• 1.87 x 1024 atoms
• 1.10 x 1023 atoms
• 3.13 x 1025 atoms

Match the formula with the correct acid name.

H2SO4

H2SO3

H2SiO3

What is the standard unit of measurement for enthalpy in the International System of Units (SI)?

• Calorie
• Gram
• Joule
• Lumen

Convert 0.789 atm to mmHg

• 649.34 mmHg
• 700.16 mmHg
• 710.66 mmHg
• 599.64 mmHg

15.0 mL of 0.500 M NaOH is used to neutralize 25.0 mL of acetic acid, CH3COOH, solution of unknown concentration. What is the concentration of the acetic acid?

• 0.30 M CH3COOH
• 0.40 M CH3COOH
• 0.35 M CH3COOH
• 0.25 M CH3COOH

 Which of the following elements has the highest electronegativity value?

• F
• N
• Li
• Be

What element is used in nuclear power plants in the nuclear fission process?

• Uranium
• Sulfur
• Boron
• Hydrogen

What groups correlate to the s sub level?

• Groups one and three
• Groups two and four
• Groups three and four
• Groups one and two

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