Michelle and Justin are carrying out an investigation into the reactivity of different metals with dilute acids. They place a small piece of each metal into a test tube of acid and observe the reaction.
1) How can they tell reaction has taken place?
2) How can you tell which metal is more active?​

Answers

Answer 1

Michelle and Justin are conducting an investigation into the reactivity of different metals with dilute acids. The two of them put a small piece of each metal into a test tube of acid and observe the reaction.

Below are the answers to the following questions:

The following are the indications that reaction has taken place: Bubbles are formed during the reaction. The formation of a solid could be observed in the test tube. The color of the acid changes.

The following are the indications that can tell which metal is more active:In the test tube of the most active metal, the reaction will be more vigorous and will produce bubbles faster. The most reactive metal will dissolve more easily in the acid than the less reactive metal. The most active metal has a higher displacement potential than the other metals.

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Related Questions

Yo I rly need help plzzz

Yo I rly need help plzzz

Answers

Ethanoic acid has the lowest vapour

The mechanical advantage of a screw can be increased by __________.

arranging the threads further apart
making it longer
arranging the threads closer together
turning it faster

Answers

The resistance and the effort force are used to calculate the mechanical advantage. Arranging the threads of the screw closer together will increase the mechanical advantage. Thus, option C is correct.

What is the mechanical advantage?

Mechanical advantage is the ratio of the output force to the input force. It allows easier task performance by obeying the conservation of mass.

The closer threads of the screws make the distance covered to be more, and the force applied will be multiplied which will be a mechanical advantage over threads placed far apart.

Therefore, option C. threads located closer have more mechanical advantages.

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A red rubber dodge ball sits in a 20.0ºC basement, filled with 3.50L of compressed air. Eager to begin practice for the impending dodge ball season, Vince reclaims the ball and takes it outside. After a few hours of practice, the well sealed ball has a volume of 3.00L. What’s the temperature outside in Celsius?

Answers

V1 / T1 = V2 / T2
3.5 / 20 = 3 / T2
T2 = 17.1 C

The temperature outside red rubber dodge ball filled with compressed air is -21.86⁰C.

New temperature of the compressed air

The new temperature of the compressed air is determined from Charles's law as shown below;

V1/T1 = V2/T2

T2 = (T1V2)/V1

where;

T1 = 20 + 273 = 293K

T2 = (293 x 3)/3.5

T2 = 251.14K = -21.86⁰C

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suppose this lab allowed you to mix two of the solutions. what type of solution would you expect to result from mixing the drain cleaner with the battery acid?

Answers

Answer:

calcium chloride because that is the answer

propanal reacts rapidly with ethylmagnesium bromide in anhydrous ether to give a (c5h12o). treatment of a with aqueous chromic acid gives b (c5h10o). draw the structure of b.

Answers

The structure of B is pentan-2-one (C5H10O).

The reaction of propanal (C3H6O) with ethylmagnesium bromide (C2H5MgBr) in anhydrous ether results in the addition of the ethyl group from the Grignard reagent to the carbonyl carbon of propanal, forming a tertiary alcohol with the molecular formula C5H12O.

Treatment of the resulting product with aqueous chromic acid (H2CrO4) leads to oxidation of the alcohol group to a carbonyl group, forming a ketone with the molecular formula C5H10O. The ketone formed is pentan-2-one, which has the structural formula CH3CH2CH2COCH3.

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A pressure saucepan reduces cooking time by:
1. increasing atmospheric pressure.
2. decreasing atmospheric pressure.
3. increasing vapor pressure.
4. decreasing vapor pressure.
5. ionizing the added salt.

Answers

A pressure saucepan, also known as a pressure cooker, reduces cooking time by increasing atmospheric pressure inside the cooking vessel. This is achieved by sealing the pot tightly and trapping steam generated from boiling liquids and food. The increased pressure raises the boiling point of water, allowing food to cook at higher temperatures than normal. Options 1 and 3 are correct.

Option 1: Increasing atmospheric pressure is correct because the sealed pressure cooker traps steam, which increases the pressure inside the pot. The increased pressure raises the boiling point of water, resulting in faster cooking times.

Option 2: Decreasing atmospheric pressure is incorrect because pressure cookers work by increasing pressure, not decreasing it.

Option 3: Increasing vapor pressure is correct because as the pressure inside the pressure cooker increases, the vapor pressure of water also increases. This higher vapor pressure enables the food to cook more rapidly.

Option 4: Decreasing vapor pressure is incorrect because the pressure cooker actually increases the vapor pressure by raising the overall pressure inside the pot.

Option 5: Ionizing the added salt is unrelated to the operation of a pressure cooker and does not contribute to the reduction in cooking time.

Hence, a pressure saucepan reduces cooking time by increasing the atmospheric pressure and vapor pressure inside the pot.

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If your cannot keep your balance, what bodily structure might be responsible?
A. Ossicles
B. Semicircular canal
C. Hippocampus
D. Occipital lobe

Answers

Answer:

d

Explanation:

If you traveled 25 meters in 100 seconds, what is your speed?

Answers

25m/100 seconds = 0.25m/sec

.25 meters per second

25/100

.25

100/100

1

Suppose cobalt-60 undergoes a type of radioactive decay that does not
change the identity of the isotope. which type of decay did the isotope
undergo?
a. delta
b. gamma
c. alpha
d. beta

Answers

i think it maybe could possibly be beta

arrange the following gases in order of increasing rate of effusion: c2h6, ar, hcl, ph3

Answers

The order of increasing rate of effusion is: C₂H₆ < PH₃ < HCl < Ar.

The rate of effusion for a gas depends on its molar mass and the temperature. According to Graham's law of effusion, the rate of effusion is inversely proportional to the square root of the molar mass. Therefore, gases with lower molar masses will effuse faster than those with higher molar masses at the same temperature.

To arrange the gases in order of increasing rate of effusion, we need to compare their molar masses:

Ar (argon): Molar mass = 39.95 g/mol

HCl (hydrogen chloride): Molar mass = 36.46 g/mol

PH₃ (phosphine): Molar mass = 33.99 g/mol

C₂H₆ (ethane): Molar mass = 30.07 g/mol

Now, we can compare the molar masses and determine the order of increasing rate of effusion:

C₂H₆ (ethane): It has the lowest molar mass among the given gases, so it will have the highest rate of effusion.

PH₃ (phosphine): It has a higher molar mass than ethane but lower than hydrogen chloride and argon. Therefore, it will have a higher rate of effusion compared to hydrogen chloride and argon but lower than ethane.

HCl (hydrogen chloride): It has a higher molar mass than both ethane and phosphine. Hence, it will have a lower rate of effusion than ethane and phosphine.

Ar (argon): It has the highest molar mass among the given gases, so it will have the lowest rate of effusion.

Therefore, the order of increasing rate of effusion is:

C₂H₆ < PH₃ < HCl < Ar

In summary, ethane (C₂H₆) will have the highest rate of effusion, followed by phosphine (PH₃), hydrogen chloride (HCl), and finally, argon (Ar), which will have the lowest rate of effusion.

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6. A sealed flask filled with an ideal gas is moved from an ice bath into a hot water bath. The initial temperature is 273K and
the final temperature is 350 K. The initial pressure is 100kPa. The volume does not change. What is the final pressure of the flask? Name the gas law.

Answers

Answer:

Explanation:

Since the volume of the gas does not change, we can use the Gay-Lussac's law (also known as Pressure-Temperature law), which states that the pressure of an ideal gas is directly proportional to its absolute temperature when the volume is kept constant. Mathematically, this can be expressed as:

P1/T1 = P2/T2

where P1 and T1 are the initial pressure and temperature, respectively, and P2 and T2 are the final pressure and temperature, respectively.

Substituting the given values in the above equation, we get:

P2 = (P1/T1) × T2

   = (100 kPa/273 K) × 350 K

   = 128.83 kPa (approx.)

Therefore, the final pressure of the flask is approximately 128.83 kPa.

if 4.50 kj of heat is supplied to a 0.560 mol sample of solid copper at 25.0°c, what will the copper’s final temperature be in °c? the specific heat of solid copper is 0.385 j/g • k.

Answers

The final temperature of copper will be approximately 28.92°C.

To find the final temperature of copper, we can use the equation:

q = m × C × ΔT

Where:

q = heat absorbed or released

m = mass of the sample

C = specific heat capacity of the substance

ΔT = change in temperature

First, let's calculate the heat absorbed by the copper using the given information:

q = 4.50 kJ = 4.50 × 10^3 J (converting kilojoules to joules)

m = 0.560 mol × molar mass of copper (Cu) = 0.560 mol × 63.55 g/mol = 35.648 g (converting moles to grams)

C = 0.385 J/g·K

Now we can rearrange the equation to solve for ΔT:

ΔT = q / (m × C)

ΔT = (4.50 × 10^3 J) / (35.648 g × 0.385 J/g·K)

ΔT ≈ 3.92 K

Finally, we can calculate the final temperature by adding the change in temperature to the initial temperature:

Final temperature = 25.0°C + 3.92 K

Final temperature ≈ 28.92°C

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Which characteristic most likely describes the water in Lake Taal?
Select the correct answer.
o The water will appear slightly red.
O The water will have a slippery feel.
The water will taste bitter.
The water will taste sour.​

Answers

Answer: The water will taste sour.

Explanation:

Answer: D. The water will taste sour (Edmentum)

Explanation:

What are the criteria of high-quality scientific research?
Provide at least three examples and explain them in detail.

Answers

High-quality scientific research is characterized by several key criteria. Three examples of such criteria include: rigorous experimental design and methodology, reliable data analysis and interpretation, and clear and transparent reporting of results.

These criteria ensure that research is conducted in a systematic and reliable manner, leading to trustworthy and valid findings.

Rigorous Experimental Design and Methodology: High-quality scientific research requires a well-designed experimental approach. This involves careful planning, proper control groups, randomization, and replication. A rigorous methodology ensures that experiments are conducted under controlled conditions, minimizing bias and confounding variables, and allowing for accurate and reliable data collection.

Reliable Data Analysis and Interpretation: After data collection, high-quality research involves thorough and appropriate analysis of the data. This includes using appropriate statistical methods to evaluate the significance of the results and drawing valid conclusions. Proper data analysis helps researchers identify patterns, trends, and relationships, supporting or refuting their hypotheses in an objective and reliable manner.

Clear and Transparent Reporting of Results: High-quality research demands transparent reporting of the methods, procedures, and findings. This includes providing detailed descriptions of the experimental setup, data collection processes, and statistical analyses used. Clear reporting allows other researchers to replicate the study and verify its results. Additionally, complete reporting ensures that readers can understand the research methodology and draw their own conclusions based on the evidence presented.

By adhering to these criteria, high-quality scientific research maintains integrity, credibility, and reproducibility. It fosters trust among the scientific community and facilitates the advancement of knowledge by building upon reliable foundations.

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According to reference Table M, what is the color of the indicator bromthymol blue in a solution that has a pH of 8?

(1) Yellow (2) Orange (3) Blue (4) Pink

Answers

Answer: Yellow

Explanation:

See attached table.

According to reference Table M, what is the color of the indicator bromthymol blue in a solution that

give two example for desert plants and animals?




please mark as brainliest​

Answers

Answer:

Plants : Cactus, tumbleweed

Animals : camel, fennec fox

Answer:

Desert plant - Cactus & Tumbleweed

Desert animal - Camel & Scorpion


For hydrogen sulfide at 188 K, H = 2380 J/mol, and S =12.6 J/mol K. Calculate the change in
Gibbs energy. Will the change be spontaneous?

Answers

the change in Gibbs energy is 5.2 J/mol, and the reaction is non-spontaneous under these conditions.

To calculate the change in Gibbs energy, we can use the equation:

ΔG = ΔH - TΔS

ΔH - change in enthalpy,

ΔS - change in entropy,

T - temperature in Kelvin.

at 188 K, ΔH = 2380 J/mol and ΔS = 12.6 J/mol K

ΔG = (2380 J/mol) - (188 K)(12.6 J/mol K)

ΔG = 2380 J/mol - 2374.8 J/mol

ΔG = 5.2 J/mol

The positive value of ΔG indicates that the reactants are more stable than the products and that energy must be added to the system to drive the reaction forward.

Therefore, the change in Gibbs energy is 5.2 J/mol, and the reaction is non-spontaneous under these conditions.

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Matter is a substance that has ________.

Answers

Answer:

matter is substance that has mass.

Answer: Mass and Volume?

Explanation:

The Sn2 reaction of 2,2 - dimethyl-1-bromopropane is significantly lower than bromoethane, even though both are primary alkyl halides. Why?

Answers

The lower reactivity of 2,2-dimethyl-1-bromopropane in the Sn2 reaction compared to bromoethane can be attributed to steric hindrance. The two methyl groups on the carbon adjacent to the bromine in 2,2-dimethyl-1-bromopropane create a bulky structure that hinders the approach of the nucleophile during the Sn2 reaction.

This hindrance slows down the reaction and makes it less favorable compared to bromoethane, which has a simpler structure with no such hindrance.

Therefore, even though both are primary alkyl halides, the presence of the bulky methyl groups makes the Sn2 reaction of 2,2-dimethyl-1-bromopropane significantly lower than bromoethane.
The Sn2 reaction of 2,2-dimethyl-1-bromopropane is significantly lower than bromoethane because of the steric hindrance in the former compound.

Both are primary alkyl halides, but 2,2-dimethyl-1-bromopropane has two methyl groups attached to the carbon bearing the bromine atom, making it more sterically hindered. This steric hindrance reduces the accessibility of the nucleophile to the reaction site, resulting in a lower Sn2 reaction rate compared to bromoethane, which has a less hindered structure.

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a. An apparatus consists of a 2 L flask containing nitrogen gas at 28◦C and 706 kPa and is joined by a valve to a 6 L flask. The valve is opened, and the gas is allowed to occupy both sides of the apparatus. What is the pressure of the gas once it reaches equilibrium in both sides?

Answers

Nitrogen gas has a pressure of 706 kPa in a 2 L flask and a pressure of 177 kPa when a 6 L flask is added, both at 28 °C.

Nitrogen gas at 28 °C and 706 kPa (P₁) occupies a 2 L flask (V₁). When a valve is opened, the gas can also occupy a 6 L flask. The total volume occupied by the gas (V₂) will be:

\(V_2 = 2 L + 6 L = 8 L\)

Assuming constant temperature and ideal behavior, we can calculate the final pressure (P₂) of the gas using Boyle's law.

\(P_1 \times V_1 = P_2 \times V_2\\\\P_2 = \frac{P_1 \times V_1 }{V_2} = \frac{706 kPa \times 2L }{8L} = 177kPa\)

Nitrogen gas has a pressure of 706 kPa in a 2 L flask and a pressure of 177 kPa when a 6 L flask is added, both at 28 °C.

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Which process in the atmosphere is responsible for moving heat from warm equatorial regions to higher latitudes

Answers

Answer:

Heat transfer in the atmosphere from the equatorial regions to higher latitudes occurs through the process of Convection

Explanation:

The equatorial regions of the earth's surface receive the most heat from the sun than any other region of the earth. This is because the are most directly in line with the direct heat from the sun.

Due to this heat from the sun, atmospheric air around the equatorial regions are hot and less dense than air in regions of higher latitudes, and thus, rises above the equator. The rising air at the equator is replaced by colder and denser air from higher latitudes north and south of the equator. As the rising air of the equatorial regions are being replaced by colder and denser air from higher latitudes, the hot and humid air moves away from the equator, toward regions of higher latitude, north and south thereby setting up a convection current of heat flow.

A scientist conducts experiments to test what temperature causes the fastest growth rate in sunflower plantsafter multiple trials the results show that sunflower plants grow the fastest at 75 FIs this experement an example of replication or repetition?

Answers

Answer:

Repetition

Explanation:

In the world of science, experiments are regularly conducted to test out hypotheses. These experiments are however, not conducted by scientist once to derive a result. They are rather conducted multiple times (repeated) to ascertain the accuracy i.e not as a result of random occurrence. The experiments that undergo multiple trials are said to undergo REPETITION.

This is the case of the scientist in this question, who is conducting an experiment to test what temperature causes the fastest growth rate in sunflower plants. He conducted the experiment multiple times, making it an example of REPETITION.

N.B: Replication is when the experiment is re-conducted by another scientist to see if same result is derived.

Which statements describe kinetic and potential energy? Check all that apply.

Answers

Answer:

Question does not show the problem in its entirety

Explanation:

An ion has 26 protons, 28 neutrons, and 24 electrons. Which element is this ion? a. Xe b. Ni c. Fe d. Mg e. Cr

Answers

The ion that has 26 protons, 28 neutrons, and 24 electrons is Iron (Fe) (option c).

An element can be determined by the number of protons in the nucleus of its atom. The number of protons present in an atom is referred to as the atomic number of the element.

This means that the number of protons in an atom is unique to a specific element.

Iron (Fe) has 26 protons in the nucleus of its atom.

Therefore, an ion with 26 protons is an ion of the element iron (Fe).

Magnesium (Mg) has 12 protons, Chromium (Cr) has 24 protons, Xenon (Xe) has 54 protons and Nickel (Ni) has 28 protons.

Thus, an ion which has 26 protons, 28 neutrons, and 24 electrons  is Fe (option c)

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Where is a mid-ocean ridge exposed above sea level?

Question 11 options:

Himalaya Mountains


Mariana Trench


The Big Island of Hawaii


Iceland

Answers

Answer:

ice land should be it

Explanation:

Answer:

Iceland is the answer.

Explanation:

Calculate the pH after 0.13 mol NaOH are added to 1.00 L of 0.50M HC2H3O2 and 0.80M NaC2H3O2 buffer solution, Ka= 1.3 x 10^-5. I really need help, I'm struggling with this topic.

Answers

Determine how many mL of solution A (acetic acid-indicator solution) must be added to solution B (sodium acetate-indicator solution) to obtain a buffer solution that is equimolar in acetate and acetic acid. Solution A: 10.0 mL 3.0e-4M bromescol green

hoped I helped

What does the oil on our bodies for and what does it help????

Answers

Answer:

keep your skin moisturized

Explanation:

but if your crowd produces excessive lubricate, it can cause blemishes. However, skilled is a bright side -- lubricate keeps skin smooth and wet, making it less inclined wrinkle

15. Why did Einstein develop the “cosmological constant”? ______________________________________________
___________________________________________________________________________________________
16. Which theory was the natural beginning of a Big Bang theory? _________________________________________
___________________________________________________________________________________________
17. Who showed that the universe was indeed expanding? ______________________________________________
18. According to the expansion law do the galaxies expand away from each other equally? Explain.
___________________________________________________________________________________________
___________________________________________________________________________________________

Answers

15. To counter the effects of gravity and allow the universe to remain static.

16. The Steady State Theory.

17. Edwin Hubble.

18. No, the galaxies expand away from each other at different rates depending on their distances.

15. Einstein created the cosmological constant in an effort to counteract the forces of gravity, preventing the cosmos from growing or contracting but keeping it static at the same size.

16. The Steady State Theory, which was put forth in the 1920s, claimed that the world is motionless and limitless, and that new stuff is constantly being produced as the universe expands.

17. American astronomer Edwin Hubble observed that galaxies were moving apart from one another, and that the farther they were from one another, the quicker they were travelling, which led him to conclude that the universe was expanding in 1929.

18. Depending on how far apart they are from one another, galaxies separate from one another at varying rates. The greater the distance between any two galaxies

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Why re-crystallization was carried out

Answers

Re-crystallization is carried out to purify solid compounds by dissolving and re-crystallizing them to remove impurities and obtain a higher-purity product.

Re-crystallization is a typical method in chemistry for removing impurities from solid substances. A solid substance is dissolved in a solvent at high temperatures, and then the solution is gradually cooled to allow the substance to re-crystallize. A higher quality product is produced as a result of this procedure, which frequently results in the exclusion of contaminants that were present in the original solid from the new crystals.

The removal of impurities from organic compounds, which frequently have a broad range of boiling points and can be challenging to purify using conventional techniques, is made possible via re-crystallization.

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differentiate between edible and non edible mushroom​

Answers

Edible mushrooms: Consuming edible mushrooms is safe and provides health advantages like fiber, vitamins, and minerals.

Examples: Button mushrooms.

Non-Edible mushrooms: Mushrooms that cannot be eaten could be harmful or have unappealing flavors and textures that could be harmful if consumed.

Examples: Death Cap.

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An internal conflict is the struggle that takes place in a characters mind while an external conflict is a struggle between a character and some outside force. Analyze how The Eclipse effectively depicts both internal and external conflicts. Write a well-organized response using specific evidence from the story to support your answer. What is the best explanation of the practice of storytelling? a. to help develop artistic and scientific talents in young people b. to pass on values and cultural norms to young people c. to change the history and values of the culture d. to help visitors understand a culture's future plans what is the first link in the adult out-of-hospital chain of survival? responses rapid defibrillation with an aed rapid defibrillation with an aed provide effective advanced life support provide effective advanced life support perform early high-quality cpr perform early high-quality cpr activation of the emergency response system How to get pH from OH- 4. In a 2-dimensional object we had 2 measures: perimeter, distance around the object, and area, the amount of space inside an object. In a 3-dimensional object we have 2 measures as well. The area on the outside of the object called and the space inside the object called The shorter leg of a triangle is 8cm shorter than the longer leg. The hypotenuse is 8cm longer than the longer leg. Your statement balance is $687.45. You have outstanding checks totaling $332.10 and an outstanding deposit for $124.21. What is your adjusted balance? Can you help me with this Spanish work plz plz plz plz Superior Micro Products uses the weighted-average method in its process costing system. Data for the Assembly Department for May appear below: Materials Labor Overhead Work in process, May 1 $ 28,300 $ 46,299 $ 225,522 Cost added during May $ 171,980 $ 30,866 $ 150,348 Equivalent units of production 2,400 2,300 2,200 Required: Compute the cost per equivalent unit for materials, labor, overhead, and in total. (Round your answers to 2 decimal places.) How many moles of tungsten atoms are there in 4. 8 x 10 atoms of tungsten? An adiabatic piston-cylinder compressor has an efficiency of 85%. If air is compressed from 101 kPa and 25 o C to 1200 kPa. Determine the actual work done and the actual final temperature. g the rules of a language that tell speakers which sounds to use and how to order them are called Jacqueline drove 72 km on 6 L of gasoline.Which of the following equations can be used to find how far she can travel on a full tank of 50 L?A. 6/72=x/50B. 72/6=50/xC. x/72=6/50D. 6/72=50/x why did many in europe and the united states feel the need to create a jewish state, israel, after world war ii? ________ produce a biological or psychological dependence in users so that withdrawal from them leads to a craving for the drugs that, in some cases, may be nearly irresistible. help I'm crying and I need this done Identify whether each of the following transactions, which are related to revenue or expense recognition, are accrual, deferral, or neither.-sold goods to customers on credit-collected cash from customer accounts-sold goods to customers for cash-collected cash in advance for goods to be delivered later-paid an expense for the current month-prepaid an expense for future months-made a payment to reduce accounts payable-incurred a current-month expense, to be paid next month a researcher decides to examine the records of the dept. of health to examine rates of hiv infection within different population groups. what type of research is this? Which objective should be in place when the microscope is put away. Sasha did an experiment to study the solubility of two substances. She poured 100 mL of water at 20 C into each of two beakers labeled A and B. She put 50 g of Substance A in the beaker labeled A and 50 g of Substance B in the beaker labeled B. The solution in both beakers was stirred for 1 minute. The amount of substance left undissolved in the beakers was weighed. The experiment was repeated for different temperatures of water and the observations were recorded as shown. Experimental Observations Substance Mass of Undissolved Substance at Different Temperatures (gram) 20 C 40 C 60 C 80 C A 12 11 9 8 B 45 40 34 31 Part 1: Which substance has a higher solubility? Part 2: Explain your answer for Part 1.