Mass, moles and the use by firefighters are not sufficient to determine the identity of a substance. To identify a substance, more information such as chemical and physical properties, chemical reactions, and spectral data are typically required.
What is mass and mole?Mass is a scalar quantity that measures the amount of matter in an object. It is typically measured in units of grams (g) or kilograms (kg). The mass of an object does not change with location, unlike weight which does change with the gravitational force acting upon it.Moles (mol) is the unit of measurement for amount of substance. It is defined as the amount of a substance that contains the same number of entities (such as atoms, molecules, or ions) as there are in 12 grams of pure carbon-12. Moles can be used to express the concentration of a solution, the number of atoms in a sample, or the amount of material in a reaction.The number of moles can be calculated by dividing the mass of a substance by its molar mass (the mass of one mole of the substance).To learn more about mass and mole refer:
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Question 1
Recall all the models you described in task 1. (Rutherford, Dalton,and Bohr) Think about the results each model would predict for Thomson's experiment. Which atomic models does Thomson's experimental evidence support? Exp why these models are compatible with the experimental results.
Thomson's experimental evidence supports Rutherford's atomic model, as it aligns with the observed behavior of the cathode rays in the cathode ray tube experiment
Thomson's experiment, known as the cathode ray tube experiment, involved passing an electric current through a partially evacuated tube and observing the behavior of the cathode rays. Thomson discovered that the cathode rays were negatively charged particles, which later came to be known as electrons. Based on Thomson's experimental evidence, it is compatible with Rutherford's model, which proposed a dense positively charged nucleus and negatively charged electrons. Thomson's experiment indicated the presence of negatively charged particles (electrons) and their deflection towards the positively charged plate, supporting the idea of a small, dense, positively charged nucleus within the atom. In summary, Thomson's experimental evidence supports Rutherford's atomic model, as it aligns with the observed behavior of the cathode rays in the cathode ray tube experiment. The experiment provided strong evidence for the existence of negatively charged electrons within atoms and the presence of a small, dense, positively charged nucleus.
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What information about a representative element can you get from just knowing its group number?
the number of electrons it has in the highest occupied energy level
the total number of electrons it has
the number of filled energy levels it has
the number of protons and neutrons it has in the nucleus
You can determine the number of electrons it has in the highest occupied energy level. Option A
Representative elements are found in Groups 1, 2, and 13-18 of the periodic table. The group number corresponds to the number of valence electrons, which are the electrons in the outermost energy level.
For example, elements in Group 1 have one valence electron, while elements in Group 18 have eight valence electrons (except helium, which has two). Knowing the group number helps predict the element's chemical properties, as valence electrons play a significant role in chemical reactions and bonding.
Information regarding the total number of electrons (B), the number of filled energy levels (C), and the number of protons and neutrons in the nucleus (D) cannot be determined from just the group number.
However, you can use the element's atomic number and electron configuration to find this information. The atomic number represents the total number of protons and electrons in an atom, while electron configuration illustrates the distribution of electrons in energy levels. Option A
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Hydroxides (oh-) are insoluble except for
Answer:
LiOH is soluble. Na2CO3 is soluble. Cu(OH)2 is insoluble.
Explanation:
LiOH is soluble. Na2CO3 is soluble. Cu(OH)2 is insoluble.
I need help calculating the error % in molar mass
What changes occur in the sky over the period of 24 hours? Why do these changes occur?
Answer:
Orientation
Explanation:
An error during which cellular process would create a gene mutation?
An error during DNA replication would create a gene mutation.
During DNA replication, the genetic information in a cell is copied to make new DNA molecules. However, mistakes can occur during this process, leading to changes in the DNA sequence, which can result in a mutation. Mutations can also be caused by exposure to environmental factors, such as radiation or chemicals, which can damage the DNA molecule directly or affect the cellular processes involved in DNA replication.
Mutations can have a variety of effects on the organism, ranging from no effect to causing serious health problems or even death. Gene mutations can also be inherited from a parent, which can result in genetic disorders or predisposition to certain diseases. Therefore, it is important to understand the mechanisms of gene mutations and their potential impacts on organisms.
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how do stars produce and release energy?
Answer:As hydrogen atoms collide to create helium, enormous quantities of energy are released, heating the gas. This process, known as nuclear fusion, is what causes stars to shine. The pull of gravity inward is resisted by the heated gas as it pushes outward.
Explanation:
Does 7period element experience inert pair effect? And why
Yes, elements in the 7th period of the periodic table can experience the inert pair effect. The inert pair effect is observed when the valence s-electrons of heavier elements (particularly in Groups 13-15) are less likely to participate in chemical bonding compared to their p-electrons.
This effect becomes more pronounced as you move down the periodic table.In the 7th period, elements such as polonium (Po), astatine (At), and tennessine (Ts) exhibit the inert pair effect. This is due to the increasing size of the atoms and the relativistic effects that come into play at higher atomic numbers.
The increased size and relativistic effects cause the s-electrons to be more strongly influenced by the attractive force of the positively charged nucleus, making them less available for bonding.
As a result, elements experiencing the inert pair effect tend to exhibit oxidation states lower than what might be expected based on their position in the periodic table. This effect has significant implications for the chemical behavior and reactivity of these elements.
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The unique properties of water are due to the water's
Question 32 options:
A. density
B. ionic bonds
C. polar nature
D. high heat capacity
Answer:
C. polar nature
Explanation:
The polarity of water and its ability to hydrogen bonding contributes to it's unique properties
Please help solve these chemistry questions!!!
Practice with percent composition.
1. What is the percent composition of Fe if 111.7 g of Fe is recovered from a 159.7 g sample of Fe2O3?
2. What is the percent composition of O if 12 g of O is recovered from a 38 g sample of Cr2O3?
3. Calculate the percent composition of KCl.
4. Calculate the percent composition of N2O5.
Practice with empirical formulas
5. What is the empirical formula for a compound that contains 0.0260 mol C, 0.0325 mol H, and 0.0065 mol O.
Practice with Molecular Formulas
6. Determine the molecular formula for a compound that has an empirical formula of NO2 and a molar mass of 138.015 g/mol.
7. Nicotine is 74.1% C, 8.6% H, and 17.3% N by mass. It’s molar mass is about 160 g/mol.
a. What is it’s empirical formula?
b. What is it’s molecular formula?
A student placed 6.0 grams of baking soda into a small balloon. The mass of the
balloon and soda was measured at 7.0 grams. Next, the student poured a measure of
vinegar into a Florence flask that had an empty mass of 100 grams. After the balloon
was stretched across the top of the flask, the student dumped the soda into the vinegar.
A gas was formed by a chemical reaction that filled the balloon. After the reaction
stopped, the student placed the flask with the filled balloon on a balance scale and it
measured 125 grams.
What was the mass of the vinegar the student put in the flask at the start?
The mass of the vinegar the student put in the flask at first is 18 grams.
How do we solve for the mass of the vinegar?To find the mass of the vinegar, you have to consider the law of conservation of mass.
Ths law says that the total mass of the reactants before a chemical reaction is equal to the total mass of the products after the reaction.
Therefore
Mass of vinegar = Total mass after reaction - (mass of flask + mass of balloon with baking soda)
= 125 grams - (100 grams + 7 grams)
= 18 grams
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Type the correct answer in the box. The density is 1.26grams/ centimeters. How many pounds/foot is this? Use the conversion rates of 454 grams/1 pound and 28,317 centimeters/1 ft.. Express your answer to the correct number of significant figures.
Answer: 78.59 lb/ft
Explanation:
use stoichiometry to solve
1.26g/cm x ( 1pound/ 454 grams) X (28317 Cm/1 ft) = 78.59 pounds/ft
If a solution has a [H+] concentration of 4.5 x 10-7 M, is this an acidic or basic solution?
Solve and Explain.
Considering the definition of pH, the pH is 6.35 and the solution is acidic.
Definition of pHpH is the Hydrogen Potential and it is a measure of acidity or alkalinity. pH indicates the amount of hydrogen ions present in a solution or substance.
Mathematically, pH is calculated as the negative base 10 logarithm of the activity of hydrogen ions:
pH= - log [H⁺]
The numerical scale that measures the pH of substances includes the numbers from 0 to 14. The pH value 7 corresponds to neutral substances. Acidic substances are those with a pH lower than 7, while basic substances have a pH higher than 7.
Acidic or basic solution in this caseIn this case, being [H⁺]=4.5×10⁻⁷ M, you can replace this value in the definition of pH:
pH= -log (4.5×10⁻⁷ M)
Solving:
pH= 6.35
Finally, the pH is lower than 7, the solution is acidic.
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When the suns radiant energy for the Earth oceans, it causes water to change state by that rating which form of energy does water vapor have
Water vapor has latent heat energy, which is absorbed or released during the process of changing states from liquid to gas or gas to liquid.When the sun's radiant energy hits the Earth's oceans, it causes the water molecules to absorb this energy and become more energized.
This leads to the water molecules breaking apart and transforming into water vapor, which is a gaseous state of water. Water vapor has a specific form of energy known as latent heat. This is the energy required to change the physical state of water from a liquid to a gas or from a gas to a liquid. The process of converting water into water vapor requires energy, and this energy is stored in the water vapor in the form of latent heat.
The amount of latent heat absorbed or released by water vapor is dependent on the temperature and pressure conditions. When the water vapor condenses back into liquid form, this latent heat is released into the atmosphere. This process plays a critical role in weather and climate patterns as it drives the movement of heat and moisture throughout the Earth's atmosphere.
In summary, water vapor has latent heat energy, which is absorbed or released during the process of changing states from liquid to gas or gas to liquid. This energy plays a vital role in the Earth's weather patterns and is a critical component of the Earth's energy balance.
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Coal provides the energy for most of the electricity that people use today.
Who benefits from the use of coal?
a everyone, either directly or indirectly
b only the people who purchase electricity
c only the people who use the electricity from coal
d only people who work in companies that mine or sell coal
Coal supplies the energy for the majority of the power that people use today, and everyone benefits, either directly or indirectly, from the usage of coal. Option A is correct.
Coal is a significant source of energy for electricity generation, and electricity is a fundamental component of modern society. The electricity produced by coal benefits everyone, either directly or indirectly. It powers homes, businesses, and industries and provides the power necessary for transportation, communication, and other essential services.
However, the use of coal can also have negative impacts on the environment and human health, including air and water pollution, greenhouse gas emissions, and coal mining accidents. It is crucial to balance the benefits and drawbacks of coal use and consider alternative sources of energy to meet the increasing energy demands sustainably. Option A is correct.
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what complex do copper sulfate and sodium hydroxide form
Answer: copper hydroxide
Explanation:
Copper(II) hydroxide is the hydroxide of copper with the chemical formula of Cu(OH)2. It is a pale greenish-blue or bluish-green solid. Some forms of copper(II) hydroxide are sold as "stabilized" copper(II) hydroxide, although they likely consist of a mixture of copper(II) carbonate and hydroxide.
Example:
2NaOH+CuSO4→Na2SO4+Cu(OH)2
What is an activated complex?
Answer:
What is meant by activated complex?
The state of the particles that is in between the reactants and products is called the activated complex. An activated complex is an unstable arrangement of atoms that exists momentarily at the peak of the activation energy barrier.
source:Gogle
Will y’all find this answer real quick for me !!
The mass (in grams) of sodium carbonate, Na₂CO₃ required to produce 85 grams of barium carbonate, BaCO₃ is 45.7 grams
How do i determine the mass of sodium carbonate, Na₂CO₃ required?The mass of sodium carbonate, Na₂CO₃ required to produce 85 grams of barium carbonate, BaCO₃ can be obtained as follow:
Na₂CO₃ + BaSO₄ -> BaCO₃ + Na₂SO₄
Molar mass of BaCO₃ = 197 g/molMass of BaCO₃ from the balanced equation = 1 × 197 = 197 g Molar mass of Na₂CO₃ = 106 g/molMass of Na₂CO₃ from the balanced equation = 1 × 106 = 106 gFrom the balanced equation above,
197 g of BaCO₃ were obtained from 106 g of Na₂CO₃
Therefore,
85 g of BaCO₃ will be obtain from = (85 × 106) / 197 = 45.7 g of Na₂CO₃
Thus, we can conclude that the mass of sodium carbonate, Na₂CO₃ required is 45.7 grams
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If matter is left in the same environment ( no heat added), will it change states? explain.
If matter is left in the same environment and no heat is added, it will not change states.
Matter in chemistry, is defined as any kind of substance that has mass and occupies space that means it has volume .Matter is composed up of atoms which may or not be of same type.
Atoms are further made up of sub atomic particles which are the protons ,neutrons and the electrons .The matter can exist in various states such as solids, liquids and gases depending on the conditions of temperature and pressure.
The states of matter are inter convertible into each other by changing the parameters of temperature and pressure.
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Unit: Acids, Bases, and Solutions
"Properties of Acids and Bases" - WS #3
Five properties that make acids different from bases include their pH, conductivity, taste, texture, and reactivity.
The names of the given acids and bases are:
1. Hydrogen fluoride
2. Potassium hydroxide
3. Hydrogen sulfate
4. Calcium hydroxide
5. Barium hydroxide
6. Hydrogen nitroxide
7. Barium hydroxide
8. Hydrogen sulfide
9. Aluminum hydroxide
10. Dihydrogen phosphate
How to differentiate acids from basesAcids can be differentiated from bases by their taste, pH, texture, reactivity, etc. Acids typically have a sour taste while bases have a bitter taste. Acids also have a pH less than 7while bases have a pH greater than 7.
Acids and bases also differ in their texture. Acids have a sticky texture while bases have a slippery texture. The conductivity of acids is also greater than those of bases.
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Which scientist wrote the Book of Optics?
O A. Warren Washington
O B. In al-Haytham
O C. Christian Doppler
O D. Galileo Galilei
The scientist who wrote the Book of Optics is In al-Haytham.
option B.
Which scientist wrote the Book of Optics?The Book of Optics presented experimentally founded arguments against the widely held extramission theory of vision (as held by Euclid in his Optica), and proposed the modern intromission theory, the now accepted model that vision takes place by light entering the eye.
The Book of Optics is a seven-volume treatise on optics and other fields of study composed by the medieval Arab scholar Ibn al-Haytham, known in the West as Alhazen or Alhacen.
Thus, the scientist who wrote the Book of Optics is In al-Haytham.
Other options such as Warren Washington, Christian Doppler and Galileo Galilei are not correct.
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Mescaline a hallucinogenic amine obtained from the peyote cactus has been synthesized in two steps from 3 4 5 trimethoxybenzyl bromide The first step is nucleophile substitution by sodium cyanide. The second step is a lithium aluminum anhydride reduction. Indicate the reactions and give the structure of mescaline
Mescaline produces a wide range of psychoactive effects when ingested, including altered perception of reality, hallucinations, and euphoria. It is a powerful psychedelic drug that has been used for centuries by Native American tribes in spiritual ceremonies
Mescaline is a hallucinogenic alkaloid that is derived from the Peyote cactus. Mescaline is a complex organic molecule that can be synthesized in the laboratory from 3,4,5-trimethoxybenzyl bromide in two steps.The first step involves nucleophilic substitution using sodium cyanide, and the second step is a reduction using lithium aluminum hydride (LAH).Here's how mescaline can be synthesized from 3,4,5-trimethoxybenzyl bromide:Step 1: Nucleophilic substitution using sodium cyanideThe reaction of 3,4,5-trimethoxybenzyl bromide with sodium cyanide results in the formation of the nitrile derivative. NaCN serves as the nucleophile in this reaction, and it replaces the bromide ion.The mechanism for this reaction involves the following steps: A nucleophilic attack by the cyanide ion on the benzyl bromide. The carbon-bromine bond breaks, and the benzyl cation is formed. A second nucleophilic attack by the cyanide ion occurs on the benzyl cation, resulting in the formation of the nitrile derivative.Here's the reaction equation for this step:Step 2: Reduction using lithium aluminum hydrideThe next step is the reduction of the nitrile derivative using LAH. LAH serves as a strong reducing agent in this reaction and reduces the nitrile derivative to the amine. The mechanism for this reaction involves the following steps: A nucleophilic attack by LAH on the nitrile derivative. This results in the formation of an imine intermediate. The imine intermediate reacts with another LAH molecule, resulting in the formation of the amine.Here's the reaction equation for this step:Mescaline structure: Mescaline is a psychoactive compound that belongs to the phenethylamine class of alkaloids. The structure of mescaline is as follows: The molecule has three methoxy groups attached to the benzene ring, and it has an amine functional group. The molecule is a white crystalline powder that is soluble in water and alcohol.
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What is the mass of a sample of NH3 containing 6.3 × 1024 molecules of NH3?
Answer:
i dont know sorry, hope you get the answer•
What are the concentration of aluminium and sulfate in a 3.0M solution of aluminum sulfate
The concentration of aluminum in the solution is 6.0M, and the concentration of sulfate is 9.0M.
In a 3.0M solution of aluminum sulfate (Al2(SO4)3), the concentration of aluminum and sulfate can be determined by considering the stoichiometry of the compound.
From the chemical formula, we can see that one molecule of aluminum sulfate contains two aluminum ions (Al3+) and three sulfate ions (SO4^2-).
The concentration of aluminum can be calculated by multiplying the molarity of the solution by the number of moles of aluminum ions in one molecule of aluminum sulfate. The concentration of aluminum would be:
Concentration of aluminum = 2 x 3.0M = 6.0M
Therefore, the concentration of aluminum in the 3.0M solution of aluminum sulfate is 6.0M.
Similarly, the concentration of sulfate can be calculated by multiplying the molarity of the solution by the number of moles of sulfate ions in one molecule of aluminum sulfate. The concentration of sulfate would be:
Concentration of sulfate = 3 x 3.0M = 9.0M
Therefore, the concentration of sulfate in the 3.0M solution of aluminum sulfate is 9.0M.
In summary, the concentration of aluminum in the solution is 6.0M, and the concentration of sulfate is 9.0M.
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Will y’all find this answer real quick for me !!
The mass (in grams) of sodium carbonate, Na₂CO₃ required to produce 85 grams of barium carbonate, BaCO₃ is 45.7 grams
How do i determine the mass of sodium carbonate, Na₂CO₃ required?First, we shall observe the balanced equation to obtain useful information. This is shown below:
Na₂CO₃ + BaSO₄ -> BaCO₃ + Na₂SO₄
Molar mass of BaCO₃ = 197 g/molMass of BaCO₃ from the balanced equation = 1 × 197 = 197 g Molar mass of Na₂CO₃ = 106 g/molMass of Na₂CO₃ from the balanced equation = 1 × 106 = 106 gFrom the balanced equation above,
197 g of BaCO₃ were obtained from 106 g of Na₂CO₃
With the above information, we can obtain the mass of sodium carbonate, Na₂CO₃ required to produce 85 grams of barium carbonate, BaCO₃. This is illustrated below:
From the balanced equation above,
197 g of BaCO₃ were obtained from 106 g of Na₂CO₃
Therefore,
85 g of BaCO₃ will be obtain from = (85 × 106) / 197 = 45.7 g of Na₂CO₃
Thus, we can conclude from the above calculation that the mass of sodium carbonate, Na₂CO₃ required is 45.7 grams
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11. The pH values of some solutions are given below pH 14.0 1.0 L 8.0 N 6.5 n P 7.0 Solution M Z (a) Identify the solution with the lowest concentration of hydrogen ion. Give reason for your (1mk) answer
Answer: 14.0
Explanation: 14.0 is a base. The more basic, the less hydrogen ion concentration.
Step 4: Compute the pH of the Solutions
The pH scale determines how acidic or basic water is. The range is 0 to 14, with 7 representing neutrality.
Thus, Acidity is indicated by pH values below 7, whereas baseness is shown by pH values above 7. In reality, pH is a measurement of the proportion of free hydrogen and hydroxyl ions in water.
While water with more free hydroxyl ions is basic, water with more free hydrogen ions is acidic. Since chemicals in the water can change pH, pH is a crucial sign that the chemical composition of the water is changing. "Logarithmic units" are used to report pH.
Each number corresponds to a 10-fold difference in the water's acidity or basicity. Ten times more acidic than water is water is water with a pH of five.
The pH scale determines how basic or acidic a substance is. We consume a variety of drinks with varying pH levels during our daily lives. A neutral material is water. The acidity of soda and coffee varies.
Thus, The pH scale determines how acidic or basic water is. The range is 0 to 14, with 7 representing neutrality.
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URGENT HELPPP PLEASE
Use the information to answer the following question.
Several groups of Chemistry students are tasked with producing aluminum chloride using solid aluminum as
reactant. The teacher provides the students with two forms of aluminum, powder and solid chunks.
Which type of aluminum should the students plan to use in order to increase the reaction rate?
A Powder, because the greater surface area will allow more collisions between reactants to occur
B Solid chunks, because the lower surface area will allow more collisions between reactants to occur
C Solid chunks, because the greater surface area will allow more collision between reactants to occur
D Powder, because the lower surface area will allow more collisions between reactants to occur
The type of aluminum the students should plan to use in order to increase the reaction rate is powder because the greater surface area will allow more collisions between reactants to occur.
The correct option is A.
How does the surface area of the reactants affect the rate of reaction?The nature of the surface area of the reactants will either decrease or increase the rate of reaction.
An increased surface area of the reactants will increase the rate of a reaction because the greater surface area will allow more collisions between reactants to occur.
A decrease in the surface area of the reactants will decrease the rate of a reaction because the greater surface area will not allow more collisions between reactants to occur.
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1. Show a correct numerical setup for calculating the molarity of the sodium hydroxide solution.
2. Determine both the total volume of HCl(aq) and the total volume of NaOH(aq) used in the titration.
To calculate the molarity of the sodium hydroxide (NaOH) solution, we need to perform a titration with a standardized solution of hydrochloric acid (HCl). Here is the numerical setup for calculating the molarity of the NaOH solution:
Measure the volume of the HCl solution used in the titration. Let's say you used 25.0 mL of 0.100 M HCl.
Calculate the number of moles of HCl used in the titration: moles of HCl = M x V = 0.100 mol/L x 0.0250 L = 0.00250 mol.
Use the balanced chemical equation for the reaction between HCl and NaOH to determine the number of moles of NaOH that reacted with the HCl. The balanced chemical equation is:
HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)
Since the stoichiometry of the reaction is 1:1 between HCl and NaOH, the number of moles of NaOH that reacted is also 0.00250 mol.
4. Determine the volume of NaOH used in the titration. Let's say you used 30.0 mL of NaOH solution.
Calculate the molarity of the NaOH solution: Molarity of NaOH = moles of NaOH / volume of NaOH solution (in L) = 0.00250 mol / 0.0300 L = 0.0833 mol/L.
To determine the total volume of HCl(aq) and NaOH(aq) used in the titration, simply add together the volumes of HCl and NaOH that were used. In this example, the total volume would be 25.0 mL + 30.0 mL = 55.0 mL.
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Which sample uses the substance(s) that Jacob and Natalie
should use to make a cold pack that will do the BEST job of
keeping food cool
The sample that uses the substance that Jacob and Natalie should use to make a cold pack that will do the best job of keeping food cool is sample 2, because it absorbs the most energy (option B).
What is endothermic process?Endothermic refers to a chemical reaction that absorbs heat energy from its surroundings. This ensures that the temperature of the surroundings is cool or has a lower temperature.
According to this question, Jacob and Natalie are asked by their science teacher to design a warming or cooling device. They make use of certain substances, however, sample 2 has the lowest final temperature of -4°C.
This shows that sample 2 absorbs the most energy, hence, would be the best for keeping the food cool.
The incomplete question is as follows:
Jacob and Natalie are asked by their science teacher to design a warming or cooling device. They decide to design a cold pack that can be used to help keep food cool. Jacob and Natalie read about different substances that can be used inside cold packs and learn that most cold packs use endothermic reactions to cool objects.
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