Chemistry in Daily Life Questions and Answers

A spray can is used until it is empty except for the propellant gas, which has a pressure of 1200 torr at 25 °C. If the can is thrown into a fire (T= 525 °C), what will be the pressure in the hot can? [use Gay-Lussac's law] 57.1 torr 3200 torr 25,200 torr 448 torr

Define Dalton's Law of Partial Pressures states that a mixture gases will have a total pressure equal to the sum of the partial pressures of each gas. If air is 80% nitrogen and 20% oxygen, with a total pressure of 1 atm, which of these is true? the partial pressure of nitrogen is 80 atm the partial pressure of nitrogen is 0.8 atm the partial pressure of oxygen is 0.8 atm the partial pressure of oxygen is 20 atm

If the surface area of reactants is larger, Select one: a. the reaction rate is generally lower. b. the rate-determining step is eliminated. c. the reaction rate is not affected. d. the reaction rate is generally higher.

A classic chemistry class demonstration is the burning of magnesium ribbon with a Bunsen bumer. In this demonstration, two chemical reactions are occurring. Of the two reactions, what is the only limiting reactant? Methane gas from the gas supply. Oxygen that combines with the burning magnesium. Oxygen consumed by the combustion in the Bunsen burner. Magnesium ribbon that is burned.

Social stratification is about inequality among ranked groups. What do such groups have or possess unequally that are also referred to as the dimensions of social stratification? means of production; land, and ownership over people shares in companies; homes; and custom-made automobiles economic wealth; home ownership; and shares in companies economic wealth; prestige; and power

Curious Carl and his lab partner need 680.96 mL of a 0.6148 M CUSO4 solution for lab. Unfortunately, all they have is 1 liter of a 1.7971 M CuSO4 stock solution. Cheryl, his lab partner, knows what to do. She begins diluting the stock solution with distilled water. How much 1.7971 M stock solution is required to make 680.96 mL of a 0.6148 M solution? a. 1990 b. 233.0 c. 616.3 d. 0.2330

A wax candle is lit and then placed into a small, closed container. After a few minutes, the candle goes out. What is the limiting reactant of the reaction described here? wax carbon dioxide oxygen closed container

Water can act as either an acid or a base, depending on its surroundings. This means water is... amphoteric. always neutral. triprotic an indicator

For this assignment, you are to attend any live musical performance of your choice (vocal or instrumental). In no less than 600 words, describe the following using at least three (3) vocabulary terms: 1) The overall description of the performance environment 2) Description of behavior (audience and performers) 3) Description of sound (musical characteristics, soundscape) 4) Reason for choosing this performance 5) Description of highlight of performance 6) Overall summary

Which of the following best illustrates the theory of delegate representation? I always vote with my my fellow party members. "I vote for what's best, even if I think the people I represent my not agree." "My job is to represent the people who elected me regardless of my point of view." Whether I vote the way my constituents prefer or the way I think is best depends on the issue.

Consider the following reaction: 4 FeS2 + 11 O2 → 2 Fe2O3 + 8 SO2 When 26.62 moles of FeS2 reacts with 5.44 moles of O2, how many moles of SO2 are formed? What is the limiting reactant? For the reactant in excess, how many moles are left over at the end of the reaction

What is stoichiometry used for? A. To determine the amount of a substance B. To determine the atoms in a formula C. To determine the shape of a molecule D. To determine the molar mass of a molecule

1.98 g of calcium chloride and 3.75 g of sodium oxide are combined. Theoretically, what mass of solid product could be formed from these amounts of reactants? What is the limiting reactant?

Pipes can get clogged due to formation of precipitates that build up in the pipes. Examples of precipitate deposits that can cause clogged pipes include magnesium and calcium oxides that result from hard water formation. Assume that calcium chloride and sodium oxide are the starting substances (reactants) in the reaction: a. Write a balanced chemical equation describing the formation of the "hard water" precipitation process, using the information in the case study. b. State the names of the products that are produced from the reaction that you wrote in part (a). c. What type of reaction(s) is/are being represented by the chemical reaction you wrote in part (a)?

K3N(s) + 2 H₂(g) KNH₂(s) + 2 KH(s) AH = -192 kJ/mol Which of the following is the most likely reason that the reaction occurs at a significant rate only if the temperature of the reaction mixture is greater than 200°C? A) The reaction is exothermic. B) ΔS for the reaction is negative. C) The reaction has a high activation energy. D) ΔG is negative at temperatures less than 200°C.

Predict and justify the sign of ΔS° for the reaction: HgO(s) ⇒ Hg(l) + ¹/2 O₂(g) ΔG = 128 kJ/mol A) ΔS is positive because AG is positive B) ΔS is negative because AG is positive C) ΔS is positive because the products have more moles of gas than the reactants D) ΔS is negative because the products have more moles of gas than the reactants

When the hydrate CaSO4 . 2 H₂O(s) is heated the reaction below occurs. CaSO4 . 2 H₂O(s) CaSO4(s) + 2 H₂O(g) a) Using the data in the table below, calculate the value of AG, in kJ/mol, for the reaction at 298 K. Substance ΔGt (kJ/mol) CaSO4 . 2 H₂O(s) -1775 CaSO4(g) -1310 H₂O(g) -221 b) Using the value you calculated for AG, would this reaction be thermodynamically favorable? Given that the value of AH° for the reaction at 298 K is +105 kJ/mol, calculate the value of ΔS° for the reaction at 298 K. Include units with your answer.

The most common source of copper (Cu) is the mineral chalcopyrite (CuFeS₂). How many kilograms of chalcopyrite must be mined to obtain 480. g of pure Cu? Express your answer numerically in kilograms.

Isotope ?-35 has an atomic mass of 35. 75% of all atoms of element? are of this form. Isotope ?-37 has an atomic mass of 37. 25% of all atoms of element ? are of this form. What is the relative atomic mass of the element?

Hydrogen sulfide is an impurity in natural gas that must be removed. One common removal method is called the Claus process, which relies on the reaction: 8H₂S(g) + 402(g)→S8 (1) +8H₂O(g) Under optimal conditions the Claus process gives 98% yield of Sg from H₂S. Part A If you started with 45.0 grams of H₂S and 40.0 grams of O₂, how many grams of Sg would be produced, assuming 98 % yield?

Automotive air bags inflate when sodium azide, NaN3, rapidly decomposes to its component elements: 2NaN3 (s)-2Na(s) + 3N2 (g) How many moles of N₂ are produced by the decomposition of 1.30 mol of NaN3?

Mark all of the items below that can be considered electrolytes ionic compounds molecular compounds weak acids strong bases

What is true about Stative Verbs? Check all true answers below. A) They express actions happening right now. B) They express states or conditions C) They can express feelings, senses, desires, or mental states D) They are usually used in a Progressive tense E) They are usually used in a Simple tense (not progressive)

What is chronological order? Arranging events in the order of time Arranging events in the order of importance Arranging events in the order of their arrangement

How many protons, neutrons and electrons are there in a neutral atom of the isotope with the nuclear symbol: 59 Fe 26

(1) Write the electron configuration for the beryllium atom. (2) Write the electron configuration for the sulfur atom.

The ideal gas law is known as PV = nRT Where P, V, n, and T refer to pressure, volume, moles and temperature respectively (these values can all change), and R has a value of 0.0821. If an experiment was run in a 0.50 L flask at a pressure of 1.058 atm in a room that was 308.76 K, how many moles were involved in the experiment? Report your answer to 3 decimal places.

A general chemistry student found a chunk of metal in the basement of a friend's house. To figure out what it was, he used the ideas just developed in class about density. First he measured the mass of the metal to be 299.5 grams. Then he dropped the metal into a measuring cup and found that it displaced 15.3 mL of water. Calculate the density of the metal. Density= g/mL Use the table below to decide the identity of the metal. This metal is most likely

Which of the following apply to the electron ? Choose all that apply. mass= 1 amu charge=-1 mass = 0 amu charge = +1 charge-0

Take powers and roots as needed on your calculator to complete the following: a = 0.556³ b5 = 112 c = 3.00^3.94 d¹.39= 2.14

Insulin is a protein that is used by the body to regulate both carbohydrate and fat metabolism. A bottle contains 325 mL of insulin at a concentration of 30.0 mg/mL. What is the total mass of insulin in the bottle?

a. When 45.045 and 47.195 are added, the answer should be based on Enter the answer with the correct number of digits. b. When 45.045 + 47.195 = 87.11 is divided by 22.54, the answer should be based on

Calculate the mass of bromobenzene in 2.04 qt of bromobenzene. The density of bromobenzene is 1.49 g/cm³.

The theory that no two electrons in the same atom can have the same four quantum numbers is described by the: a) Aufbau Principle b) Pauli Exclusion Principle c) None of these choices is correct d) Heisenberg's Uncertainty Principle

A copy of your chemistry textbook is found to have a length of 0.265 meters. Using unit analysis, show what the length of the copy of your chemistry textbook is in millimeters.

How many MOLES of carbon tetrafluoride are present in 1.04 grams of this compound? How many GRAMS of carbon tetrafluoride are present in 3.11 moles of this compound?

Over the years, the thermite reaction has been used for welding railroad rails, in incendiary bombs, and to ignite solid fuel rocket motors. The reaction is Fe₂O3(s) + 2Al(s) → 2Fe() + Al2O3(s) Click here to see the reaction. What mass of aluminum must be used to produce 93.81 g of iron?

What does it mean ti say that the cell is 33% effective in storing the energy from the complete metabloism of glucose?

What is the ppm of Ca²+ in a 15 mL of solution if it is found that there is 98 micro-grams of calcium in the sample? (1 gram = 1,000,000 micro-grams)? O 0.15 ppm O 98 ppm O 15 ppm O 6.5 ppm

On a piece of scratch paper draw structural formulas for all of the constitutional isomers that would be named as a dichloroethane. The number of compounds is

You have two beakers on your lab table. Beaker #1 contains 32.07 g of sulfur and Beaker #2 contains 74.92 g of arsenic (As). Which beaker contains the greatest number of atoms? Choose the best answer. Beaker #1 because one sulfur atom weighs less than one arsenic atom so you need more of the sulfur atoms to fill the beaker. Beaker #1 because it contains more moles of sulfur atoms than the number of moles of arsenic atoms in Beaker #2. Beaker #2 because arsenic has a greater mass than sulfur. Beaker #2 because it contains more moles of arsenic atoms than the number of moles of sulfur atoms in Beaker #1. Beakers #1 and #2 contain the same number of atoms because there is one mole in each.

Show all your work! 1. Calculate the specific heat for an object that absorbs 145 J of heat and has 35.6 g and changes from 58°C to 74°C.

Lemon juice can be used to remove the odor of fish on a person's hands after cleaning fish. The chemical explanation for this is that the pleasant odor of the lemon juice covers the fishy odor acid in the lemon juice reacts with the odor-causing amines to form an odorless ammonium compound lemon juice dilutes the odor-causing amines O lemon juice removes the bitter flavor often associated with nitrogen compounds

Arrange the fatty acids from highest melting point to lowest melting point. CH3(CH2)5CH=CH3(CH2)12COOH CH3(CH2)12COOH CH3(CH2)4(CH=CHCH2)4(CH2)2COOH CH3(CH2)16COOH

The rate constant for the reaction below was determined to be 3.241x10^-5 s^-1 at 800 K. The activation energy of the reaction is 235 kJ/mol. What would be the value of the rate constant at 9.10×10^2 K? N2O(g) --> N2(g) + O(g)

Calculate the moles in 644.0 mL of a 0.275 M solution.

Calculate the number of oxygen atoms in 2.00 moles of Mn2O7. Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer a 8.43x10^24 atoms b 1.20x10^24 atoms c 444 atoms d 14.0x10^24 atoms

Avogadro's number is unfathomably big. To give us some perspective, let's think of if it terms of time. Consider one mole of seconds. That's 6.02x10^24 seconds. How many trillions of years is that?

a. Is condensing water vapor an exothermic process or an endothermic process? exothermic endothermic b. Is burning gasoline an exothermic process or an endothermic process? exothermic endothermic c. Is freezing ice cream an exothermic process or an endothermic process? exothermic endothermic

9. Why is wood considered to be an insulator and metal is considered to be a conductor of energy? * A. Metals have freely moving electrons, and wood is bound together in molecules held in place. B. Metals have electrons bound in molecules and wood has open spaces where electrons can move freely. C. Metals have networks with a framework of ions, and wood forms interlocked layers of electrons. D. Metals do not conduct heat, and wood does.