Chemistry in Daily Life Questions and Answers

Length of Number of leaves Lamp power Percentage Number of clipping on clipping (watts) of light that oxygen reaches the bubbles plant formed in 10 minutes A 12 9 40 100% ? B 12 9 40 75% ? C 12 9 40 50% ? D 12 9 40 25% ? 7. Refer to the diagrams in Model 2 to complete the data table in model 3. 8. The column headings in Model 3 each describe a variable in the experiment. (a) What variable was purposefully changed in the experiment? (b) What variable changed as a result of changing the variable listed in part a? (c) What variable(s) in the Model 3 data table remained constant among all the trials?

Complete and balance each of the equations below. Refer to Figure A in the instruction of Part-A (the activity series table) to determine if a single displacement reaction will occur. If you determine that there will be no reaction, write "NR” next to the balanced equation. Note: For this experiment only, assume that copper and lead will form +2 cations. (b) Cl₂ + NaBr(aq) →

Which of the following are examples of water releasing energy? Check all that are true. (A) condensation on a bathroom mirror after a hot shower (B) a puddle evaporating (C) a lake's surface water freezing over (D) frost on a windowpane caused by deposition (E) ice cubes melting

A student attended an event at a traditional tea room that offered sugar cubes instead of sugar packets. She added two sugar cubes to a cup of hot tea. After she finished drinking the tea, she was surprised to see two small chunks of undissolved sugar at the bottom of her cup. All the sugar dissolves in tea of the same temperature when added from a packet. Which of the following BEST explains why sugar remains undissolved from cubes but not from packets? 1. Adding a cube decreases the likelihood of stirring the tea, whereas adding a packet reminds people to stir. 2. Unlike the packet, the cube is compacted so not all sugar molecule surface areas contact the tea. 3. Unlike a the tea cup with cubes, tea with packets is served in a bigger cup that allows for more tea. 4. The temperature of the tea with cubes was lower than the one with packets.

Which of the following variables would not affect the equilibrium state of the reversible reaction below? N₂ (g) + O₂(g) ⇋ 2 NO (g) Nitrogen, Oxygen, Nitrous oxide ○ Amount of Nitrous Oxide ○ Amount of Oxygen Gas ○ Pressure ○ Amount of Nitrogen Gas ○ Temperature O None of these

Thermal pollution is caused when_____water is released into waterways. This causes the amount of______in the water including oxygen, to________.

Choose the correct statement for the blank to complete the following sentence: In the radical chlorination of methane, _______________ is the rate-determining step. hv (1) Cl-Cl => 2Cl° (2) CH4 + Cl° => CH3° + HCL (3) CH3° + Cl-Cl => CH3Cl + Cl° (4) Cl° + CH3° => CH3Cl (5) CH3° + CH3° => CH3CH3 (6) Cl° + Cl° => Cl-Cl (a) step (1) (b) step (2) (c) step (3) (d) step (6)

Calculate the number of Liters present in 2.9x10²³ molecules of CO.

Use the reaction below to answer the question. PCI5 (g) ⥨ PCl3 (g) + Cl₂(g) (△H=67kJ/mol) If the reaction is at equilibrium, and a scientist adds more Cl₂ to the reaction, what will happen? The amount of reactants will increase and the amount of products will decrease. All of these answers are correct. The reaction will shift left More PCl5 will be produced There will be less PCl3

What is the mass, in grams, of 4 moles of CO₂?

Calculate the number of moles present in 8.7 x 10²⁴ molecules of H₂O. [Hint: use dimensional analysis to solve!]

The mass of 1 mole of H2X is 34 grams. X must represent which element? (A) S (B) Cl (C) O (D) Kr

What is the volume, in Liters, of 0.55 moles of CO₂? [Hint: use dimensional analysis to solve!)

Draw the Lewis structure for PCI3 and use your Lewis structure to answer the following: Number of electron groups around P: Electron domain geometry: Number of bonding groups around P: Number of lone pairs around P: Molecular geometry:

Use the reaction below to answer the following questions. Use the factor-label method shown in the notes. 2NaClO₃ --> 2NaCl + 3O₂ 1. If 12.0 grams of NaClO₃ are decomposed, how many grams of oxygen will form? 2. If 80.0 grams of oxygen (O₂) are produced, how many grams of NaCl must also have been produced?

Identify each of the following equations as a synthesis, decomposition, single, or double displacement, or combustion reaction. Write a balanced chemical equation for each and include all states of matter. a) zinc + hydrogen chloride -->zinc chloride + hydrogen b) aluminum + iron (III) oxide -->aluminum oxide + iron c) iron + sulphur --> iron (III) sulfide d) sodium chloride + silver sulfate --> sodium sulfate + silver chloride

What are the coefficients FeS + O₂ →→ __Fe₂O3 + __SO2 cannot be done 1, 3, 1.4 2, 3, 2, 4 4. 7. 2,4

Using the Ideal Gas Law (PV = nRT), calculate the grams of O₂ produced in the reaction. (Hint: solve for n, and then convert moles to grams. Don't forget to convert your temperature from Celsius to Kelvin.) Show your work.

Atmospheric pressure depends on the altitude (or height) of your location. How should the air pressure change if you traveled from Los Angeles, California to Denver, Colorado, which is 1.5 kilometers (1 mile) above sea level?

Industrial deep-sea divers must breathe a mixture of helium and oxygen to prevent a disorienting condition known as nitrogen narcosis. If a diver's tank is filled with a helium-oxygen mixture to a pressure of 170 atmospheres and the partial pressure of helium is 110 atmospheres, the partial pressure of the oxygen is - 280 atm 140 atm 110 atm 60 atm

To remove the sand first and then the salt from a mixture of sand and salt water, a combination of techniques you could use would be to- filter then evaporate filter then condense evaporate and then condense evaporate then distill

According to Charles' law, the volume of a fixed amount of gas is directly proportional to- kelvin temperature isoelectric mixture barometric pressure vapor concentration

STP stands for standard temperature and pressure. Standard temperature is equal to 0 Kelvin 20.0°C O-273 °Celcius 273 Kelvin

What is the molarity of a bleach solution that contains 5.0 g of NaCIO per 500.0 mL of bleach?

What volume (in mL) of a 3.00 M iron (III) nitrate solution (Fe(NO3)3) would contain 1.75 moles of the compound? 5250 mL 583 mL 1710 mL 5.25 mL

A measure of the amount of a substance dissolved in a specific amount of solution is called the____of the solution. temperature dilution molar volume concentration

A sample of helium has a volume of 45 mL at 20.0°C and 203.0 kPa. If the pressure is constant, what is the volume of the sample at 10.0°C? 900 mL 47.5 mL 43.5 mL 22.5 mL

Kira dissolved different solutes in 100 mL of water. She recorded the amount of each solute that would dissolve at different temperatures. What information will this investigation confirm? The effect of the solvent on the temperature of the solution. The effect of temperature on the amount of solute dissolved. The temperature of the solution is dependent on the kind of solute used. The temperature of the solution is dependent on the amount of solute.

Soda water is a solution of carbon dioxide in water. The solution is composed of a liquid solute in a gaseous solvent gaseous solute in gaseous solvent gaseous solute in liquid solvent liquid solute in a liquid solvent

Sucrose (sugar) molecules dissolve easily in water because both sucrose molecules and water molecules are___molecules. covalent nonpolar polar tetrahedron

When a concentrated solution is diluted by the addition of more solvent, which of the following does NOT change? moles of dissolved substance mass of the solution volume of the solution molarity of the solution

Molly is trying to increase the boiling point of a solution of solid NaOH in water. Which of the following would help? heating the solution decreasing the pressure adding more NaOH adding more water

. At STP, which of the following would have the same number of molecules at 1 L of C₂H4 gas? Assume that each behaves as an ideal gas. 1 L of Ne gas 2 L of H₂O gas 0.5 L of H₂ gas 3 L of Cl₂ gas

An ice skating rink has tubes under its floor to freeze the water. Salt water is cooled well below the freezing point of water and pumped through the tubes to freeze the water in the rink. Why can the salt water be cooled so low without freezing? Salt has a very low freezing point. Adding salt to the water lowers its freezing point Movement of the water through the tubes keeps it in the liquid state. The salt water is constantly absorbing energy from its surroundings.

Upload a picture of your work and your answer. Round to the hundredths place, and use units. * H₂S + 2KOH → 2H₂O + K₂S Part 1: 42g of H₂S and 61g of KOH start a reaction. What is the limiting reagent?

What is the molarity of an aluminum acetate (Al(C₂H3O2)3) solution that has 0.333 moles dissolved in 0.250 liters? 0.00774 M 1.2 M 0.75 M 1.33 M

Sodium reacts violently with water in the forward direction according to the equation: 2 Na(s) + 2 H₂O(1) → 2 NaOH(aq) + H₂(g) What are the signs of ΔH and ΔS for this reaction? A) ΔH is negative and ΔS is negative. B) ΔH is negative and ΔS is positive. C) ΔH is positive and ΔS is negative. D) ΔH is positive and ΔS is positive. E) ΔH is positive or negative and ΔS is negative F) ΔH is positive or negative and ΔS is positive.

A reaction has AH-60.9 kJ/mol and AS-266.6 J/K. Is this reaction spontaneous or nonspontaneous? At what temperature (if any) can the spontaneity be reversed? A) nonspontaneous, can be made spontaneous at 228 K B) nonspontaneous, cannot be made spontaneous at any temperature C) spontaneous, can be made nonspontaneous at 228 K D) spontaneous, cannot be made nonspontaneous at any temperature

Draw each molecule from your lab showing its bonding orbitals. Label each orbital as an s, p, sp, sp2 or sp3 orbital. Show the Overlap of bonding orbitals. Put electron pairs where they belong in the orbitals. Label each bond as a s or p bond.

Which was reduced and which was oxidized? PH3 + NO₂ -> H3PO4 + N₂ H was reduced, P was oxidized N was reduced, P was oxidized P was reduced, N was oxidized N was reduced, H was oxidized

When hydrogen gas is passed over solid stannous oxide, the following reaction occurs. SnO₂ (s) + H₂ (g) = 2 H₂O (g) + Sn (s) If the system is stressed by adding additional Sn, the system will respond by If the system is stressed by adding additional H₂, the system will respond by

Determine whether of each of the following changes in reaction conditions will increase or decrease the rate of a reaction. Increasing the temperature will Using gaseous instead of solid reactants will

Assume solid Glucose (CHO) and Oxygen gas are the starting substances (reactants) in the reaction. a. Predict the products of the reaction above and write the balanced molecular equation for this reaction. b. What type of reaction (s) is/are being represented by the chemical reaction in part (a)? c. Is this reaction an oxidation-reduction (redox) reaction?

Which of the following equations represents an oxidation-reduction reaction? Ca(OH)₂ (s) + H₂SO4 (aq) → 2 H₂O(1) + CaSO4(s) CaO(s) + H₂O(l) → Ca(OH)₂ (s) Zn(s) + Cu(NO3)₂ (aq) → Zn(NO3)₂(aq) + Cu(s) AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq)

Identify the type of chemical reactions in the following processes: (i) Barium chloride solution is mixed with copper sulphate and a white precipitate is formed. (ii) On heating copper powder in a china dish, the surface of copper powder becomes black. (iii) On heating green ferrous sulphate crystals, reddish brown solid is left as residue and a gas having smell of burning sulphur is evolved. (iv) Iron nails when left dipped in blue copper sulphate solution become brownish in colour and blue colour of copper sulphate solution fades away. (v) Quicklime reacts vigorously with water releasing large amount of heat. (vi) Silver nitrate solution reacts with sodium chloride solution and a white precipitate is formed.

7. Assume solid Glucose (C4H12O6) and Oxygen gas are the starting substances (reactants) in the reaction. d. If this is a redox reaction, then identify the following: • What is undergoing oxidation (what is being oxidized)? Support your answer using oxidation numbers. What is undergoing reduction (what is being reduced)? Support your answer using oxidation numbers. • What is the reducing agent? • What is the oxidizing agent?

Many nations colonized were rich in natural resources. How did Social Darwinists view the mining of natural resources in these colonized lands? a. It was their right to take what they wanted b.It was a necessity for their countries to survive c. It was a way to preserve traditional economies d. It was a away to protect Africans from the Industrial Revolution

A balloon contains 146 mL of gas confined at a pressure of 1.30 atm and a temperature of 5 C. If the pressure doubles and the temperature decreases to 2 C, what will be the volume of gas in the balloon. 89 mL 54 mL 61 mL 72 mL

Given the following equation: Cu + 2 AgNO3 + Cu(NO3)2 + 2 Ag How many grams of Cu would have to react to produce 89.5 grams of Ag? g Your answer should be rounded to three significant figures. Do not include units in your answer.

How does increasing the temperature of a system affect the rate of chemical reactions? The activation energy increases so the reaction rate increases The activation energy increases so the reaction rate decreases The kinetic energy of the reactants increases, so the frequency of effective collision decreases The kinetic energy of the reactant increases, so the frequency of effective collision increases. Reaction rate is not affected by temperature