Chemistry in Daily Life Questions and Answers

This question is based on the following paragraph. The back yard was covered in late afternoon sunlight. The leaves danced in the trees, delighted that spring had finally arrived. The tulips were bright slashes of color like a child's crayon drawing. In the garden, the first green shoots were pushing out of the soil to greet the warmth of the sun. Sitting on the porch swing, I drank in the beauty of nature, a delicious treat. Which phrase from the paragraph is an example of a metaphor? A. Greet the warmth of the sun B. In late afternoon sunlight C. Delighted that spring had finally ved D. The beauty of nature, a delicious treat

Enthalpy change is the Select one: a. pressure change of a system at constant temperature. b. entropy change of a system at constant pressure. c. temperature change of a system at constant pressure. d. amount of energy absorbed or lost by a system as heat during a process at constant pressure.

Identify each category of substance as soluble or insoluble in water. Salts of Group 1 elements Choose... Most nitrate salts Choose... Most carbonate and phosphate salts Choose... Most halide (Br, Cl, and I) salts Choose... Most silver salts Choose...

An aqueous solution at 25 °C has a pOH of 12.62. Calculate the pH. Be sure your answer has the correct number of significant digits.

In the story of Icarus, the Exposition (establishing the setting and the conflict of the story) is A. the explanation that Icarus and his father are prisoners and want to escape. B. the detail of Icarus falling into the sea. C. the details of how Icarus' father made the special wings.

What is the mass of potassium sulfate in 500 mL of a 1.25 M potassium sulfate solution? We know the volume (500 mL or 0.5 L) and we know the moles per liter, 1.25 M, but we need mass. Solution: • First, determine how many moles we have in solution: 125 x 0.500 L = 0.625 mol • Then, convert that amount to grams. To do this you must get the molar mass of K,SO, from the periodic table 174,3 g/mol. Use the number of moles you calculated above to find grams of potassium sulfate W 0.625 mol x 1743 g K, SO, mal K, 50, = 109 g K₂ SO4 Therefore, the mass of the K₂SO, that dissolves in 500 mL of H₂O to make this solution is 109 g. Solve this problem on paper, then submit your answer to see the solution: How many grams of Ca (OH), are needed to make 100.0 mL of 0.250 M solution?

All BUT one action would increase the rate at which solid metal will react with an acid solution. That is Select one: a. decrease the molarity of the acid. b. break the metal into smaller pieces. c. increase the temperature of the solution. d. increase the concentration of the acid solution.

A sample of a substance burns more rapidly in pure oxygen than in air. Which factor is most responsible for this high rate of reaction? Select one: a. concentration of the substance b. the properties of the reactants c. temperature d. surface area exposed to air Clear my choice

In a chemical reaction, when particle size is reduced, the rate of reaction increases because of increased surface area of the reactants. Why would increased surface area increase reaction rate? Select one: a. It decreases the activation energy. b. It increases the number of collisions among particles. c. It decreases the temperature. d. It increases the concentration.

Some dry chemicals can be used to put out forest fires. One of these chemicals is NaHCO3. When NaHCO3(s) is heated, one of the products is CO₂(g), as shown in the unbalanced equation below. NaHCO3(s) + heat → Na₂CO3(s) + H₂O(g) + CO₂(g) A. Balance the above equation using smallest whole number coefficients. B. Identify the type of chemical reaction represented by the above equation. C. Draw a potential energy diagram to show that the above reaction is endothermic.

What is entropy a measure of? A. The maximum potential energy of a system B. The change in energy of a reaction C. The disorder of a system D. The energy available to do work

Through what process is heat transferred between the warm air in front of a fireplace and the cooler air on the other side of the room? A. Radiation B. Convection C. Conduction D. Absorption

Be sure to answer all parts. Carry out the following conversion. Report answers to appropriate number of significant figures. a. 354 kcal to kJ b. 11.7 kcal to J kJ J

What is the change in enthalpy of the first reaction below, given the enthalpies of the other two reactions? 2NO₂(g) →2NO(g) + O₂(g) N₂(g)+0₂(g) → NO(g) N₂(g) +O₂(g) → NO₂(g) ΔH°-90 kJ/mol ΔH-34 kJ/mol A. -112 kJ B. 112 kJ C. 248 kJ D. -56 kJ

Which statement explains why a strip of sulfur is a better electrical insulator than a strip of silicon? A. Sulfur atoms have more protons than silicon atoms. B. Sulfur atoms allow fewer electrons to move between atoms than silicon atoms do. C. Sulfur atoms allow more electrons to move between atoms than silicon atoms do. D. Sulfur atoms have fewer protons than silicon atoms.

During a test trial, the control and test group are both given a pill. To account for the effect patients may think the drug being tested is having just because they believe they're being treated, the control group is given a "sugar pill," which is called what? A. screening tool B. placebo C. drug D. medicine

A young scientist wants to focus on drug creation. What is one of the first things he should do? A. Test a composite material in the lab to see how it can be improved. B. Look into trends of various diseases and their effects on society. C. Research available drugs for treating illnesses such as cancer and heart disease, as well as the side effects of these drugs. D. Make a plan for how to conquer a disease with drugs.

Why are no unauthorized experiments permitted in the lab? A. The student lacks experience in the lab B. Most professors love to sée only their selected experiments performed C. The stockroom may not have the reagents that you need D. It may take more time to perform than expected

Some vitamins and dietary supplements are stored in opaque, darkened bottles to protect them from UV light because UV light would cause a reaction. Which word could be used to describe UV light in this situation? A. Reactant B. Catalyst C. Solvent D. Enzyme

You ask a classmate to measure the mass of a large beaker, and they record a mass of 22.5 ounces. However, you wish to know the mass in kilograms. Convert this mass to kilograms (kg) and report below to the correct number of significant figures. You can show your work here or on a separate sheet of paper to receive partial credit for your answer.

A chemist dissolves 197. mg of pure nitric acid in enough water to make up 260. mL of solution. Calculate the pH of the solution. Be sure your answer has the correct number of significant digits.

A chemist makes 790. mL of zinc nitrate (Zn(NO3)₂) working solution by adding distilled water to 70.0 mL of a 0.521 M stock solution of zinc nitrate in water. Calculate the concentration of the chemist's working solution. Be sure your answer has the correct number of significant digits.

Each row of the table below describes an aqueous solution at about 25 °C. Complete the table. That is, fill in any missing entries in the second and third columns. Be sure each entry you write includes the correct number of significant digits.

Describe the procedure for smelling a chemical. A. Stick your nose close to the vessel and breath deeply B. Point vessel away from face while gently fanning vapors toward nose C. Never smell a chemical D. Smell chemical as you would anything else

Calculate the volume in milliliters of a 0.679M barium chloride solution that contains 75.0 mmol of barium chloride (BaCl₂). Be sure your answer has the correct number of significant digits.

Each sketch below shows three objects with an electric charge. In each case, decide whether there is a net force acting on the object outlined in green. If there is a net force, decide whether it pushes the green-ring object to the left or right. Then select the appropriate button under the sketch. For example, if there is a net force pushing the green-ring object in the first sketch to the left, select the left button under the first sketch. If there is no net force on the green-ring object in the second sketch, select the middle button under the second sketch. And so on.

Volatile solvents can cause irritation of the respiratory tract, intoxication, central nervous system depression, drowsiness, or nausea. How can you prevent accidental vapor inhalation? 1. work with volatile solvent in your student hood 2. cover containers of them if you have to carry them through the lab 3. both

A chemist dissolves 374. mg of pure hydroiodic acid in enough water to make up 250. mL of solution. Calculate the pH of the solution. Be sure your answer has the correct number of significant digits.

A chemist prepares a solution of iron (II) bromide (FeBr₂) by measuring out 3.00 g of FeBr₂ into a 300. mL volumetric flask and filling to the mark with distilled water. Calculate the molarity of Br anions in the chemist's solution. Be sure your answer is rounded to the correct number of significant digits.

A chemist prepares a solution of vanadium(III) bromide (VBr3) by measuring out 3.00 g of VBr3 into a 300. mL volumetric flask and filling to the mark with distilled water. Calculate the molarity of Br anions in the chemist's solution. Be sure your answer is rounded to the correct number of significant digits.

Suppose a student starts with 2.3816 g of a sand mixture and separates the components, recovering 1.3012 g of NaC1, 0.5809 g of SiO2, and 0.4503 g of CaCO3. What is the percent recovery of the mixture?

10 An aqueous solution at 25 °C has a OH concentration of 1.7 x 107 M. Calculate the H₂O concentration. Be sure your answer has the correct number of significant digits.

List the common prefixes in order of increasing number of atoms. (Place the largest number of atoms on the bottom.) Place these in the proper order. Penta Hepta Nona Tri

Be sure to answer all parts. Give the symbol for each ion. cobalt(II):

Be sure to answer all parts. Write the formula for the ionic compound formed from each cation and anion. a. potassium and bisulfite b. barium and acetate

2 NO₂ (g) = N₂O₂(g) + 58.8 kJ What happens to the equilibrium if the temperature is increased? More NO2₂ will be formed. The equilibrium will remain the same A new product will form. More N₂04 will be formed.

In ionic compounds, metals form _ whereas nonmetals form _ For a main group element, the charge of its ion can be determined from the _ number.

Using the trends in the periodic table, rank the following atoms in order of increasing electronegativity. a. O, C, Be b. B. O, N

How much energy does a 10.0 g sample of water absorb as energy in the form of heat if its specific heat is 4.2 J/(g-°C) and it is heated from 10.0°C to 40.0°C? a.1.26 kJ b. 30°C c. 12.6 joules d. 300 joules e. some other answer

For the following reaction, 25.1 grams of carbon disulfide are allowed to react with 98.1 grams of chlorine gas. carbon disulfide(s) + chlorine(g) → carbon tetrachloride(1) + sulfur dichloride(s) What is the maximum amount of carbon tetrachloride that can be formed? What is the FORMULA for the limiting reagent? What amount of the excess reagent remains after the reaction is complete?

All of the following are characteristics of metals except: malleable. ductile. often lustrous. tend to gain electrons in chemical reactions. good conductors of heat.

The so-called Zoot Suit Riots in Los Angeles in 1943 were a result of Oracial tensions related to the huge influx of laborers from Mexico. the enforced rationing of consumer goods. opposition to policies requiring racial segregation of factory workers. the establishment of internment camps for resident aliens.

Aqueous hydrobromic acid (HBr) will react with solid sodium hydroxide (NaOH) to produce aqueous sodium bromide (NaBr) and liquid water (H₂O). Suppose 4.05 g of hydrobromic acid is mixed with 2.7 g of sodium hydroxide. Calculate the maximum mass of water that could be produced by the chemical reaction. Round your answer to 3 significant digits.

The Presence of Love by Samuel Taylor Coleridge And in Life's noisiest hour, There whispers still the ceaseless Love of Thee, The heart's Self-solace and soliloquy. You mould my Hopes, you fashion me within; And to the leading Love-throb in the Heart Thro' all my Being, thro' my pulse's beat; You lie in all my many Thoughts, like Light, Like the fair light of Dawn, or summer Eve On rippling Stream, or cloud-reflecting Lake. And looking to the Heaven, that bends above you, How oft! I bless the Lot that made me love. Friendship Relationships Love Revenge

195.0 liters of a gas in a flexible-walled container are prepared at 718.0 mmHg and 243.0 °C. The gas is placed into a tank under high pressure. When the tank cools to 19.0 °C, the pressure of the gas is 34.0 atm. What is the volume of the gas?

How do the authors use historical evidence to support their claim? Select two options. (a)They use a secondary source to show that the British secretary of war opposed involuntary servitude. (b)They use a primary source to show that a song was spreading the idea of equality across the Caribbean. (c)They use a secondary source to show that the idea of an enslaved people's revolt was groundbreaking. (d) They use a statistic to show that England had enough voters to end slavery and establish equality. (e)They use a primary source to show that some white people opposed the idea of freeing enslaved people.

A person opens a 2-liter bottle of cola at a picnic. If the cap is left off the bottle, the cola will become "flat" or lose its carbonation. Which statement below BEST summarizes why the cap must be kept tightly in place if the cola is to remain fresh? Select one: a. The cap keeps the atmospheric gases and liquid from mixing in the bottle. b. The cap keeps warm air from entering the two-liter bottle and raising the temperature of the cola solution. c. The cap keeps the pressure of the gas in the bottle at a high level preventing carbon dioxide from leavingthe solution. d. The cap prevents the liquid in the cola from evaporating.

A tire contains 1.16 moles of gas and has a volume of 5.99 L. A leak results in a deflated tire with a volume of 1.93 L. How many moles of gas remain in the tire? Assume the temperature and pressure remain constant.

After the Civil War ended, how was the North affected economically? (A)The agricultural economy suffered and declined. (B) Industry thrived and the economy soon recovered. (C)The rise in inflation bankrupted many businesses. (D)Economic uncertainty caused businesses to fail.

Spontaneous reactions are driven by; a. increasing enthalpy and increasing entropy. b. decreasing enthalpy and decreasing entropy. c. increasing enthalpy and decreasing entropy. d. decreasing enthalpy and increasing entropy.