Here are some potential questions and hypotheses for a stem fair project on cell phone radiation:
Question: Does the distance between a cell phone and a person's head affect the level of radiation exposure?
Hypothesis: If a cell phone is held closer to a person's head, then the level of radiation exposure will be higher.
Question: Do different types of cell phone cases affect the level of radiation exposure?
Hypothesis: If a cell phone is covered by a case made of a certain material, then the level of radiation exposure will be lower.
Question: How does the amount of time a person spends on their cell phone affect their level of radiation exposure?
Hypothesis: If a person spends more time on their cell phone, then their level of radiation exposure will be higher.
It's important to note that these are just a few potential ideas, and you may want to come up with your own question and hypothesis based on your interests and the resources available to you. It's also important to conduct thorough research and use reliable sources to support your conclusions.
What are the values of ΔS for the water, the surroundings, and the universe for the evaporation of water from an open pan at 25°C?
positive, negative, positive
negative, negative, negative
positive, negative, zero
positive, negative, negative
The values of ΔS for water, the surroundings and the universe for the evaporation of water from an open pan at 25°C are positive, negative and positive respectively.
The process involves conversion of water in the liquid state to water in the gaseous state.
H₂O(l)→H₂O (g)
The entropy of a gas is more than that of the entropy of a liquid. Therefore ΔS of water is positive.
In this process, energy from the surroundings needs to be suppiled in order for the conversion of liquid to gas. So, entropy of surroundings decreases. i.e ΔS of surroundings is negative.
The process is spontaneous which means that it obeys the second law of thermodynamics i.e the increase in entropy of liquid water is larger than the decrease in entropy of the surroundings. Therefore, ΔS universe is positive.
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if the combustion of 42.62 g of c4h10 produces 87.85g of co2. what is the percent yield of the reaction? (assume oxygen is in excess.)
The balanced chemical equation for the combustion of C4H10 is C4H10 + 6O2 → 4CO2 + 5H2O.
So,
The moles of C4H10 consumed in the reaction is 42.62 g / (58.12 g/mol) = 0.732 mol.
The moles of CO2 produced in the reaction is 87.85 g / (44.01 g/mol) = 1.99 mol.
The percent yield of the reaction is (1.99 mol CO2 / 0.732 mol C4H10) x 100% = 271.7%.
Define Combustion?
Combustion is a chemical reaction between a fuel and an oxidizer where heat and light energy is released. It is also referred to as burning. In the case of fossil fuels, the fuel is mainly hydrocarbons and the oxidizer is the oxygen in the air. The reaction is exothermic and produces water, carbon dioxide, and other byproducts.
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Guyton de Morveau, a French chemist, created a system for naming compounds that is still used today. For example, he said that a compound of zinc and chorine is called zinc chloride. Which of the
following is true about de Morveau's naming system?
A. The non-metallic atom is last.
B. The metallic atom is last.
C. The larger atom is first.
D. The smaller atom is first.
In de Morceau's nomenclature scheme, the smaller atom appears first.
What naming scheme is used?Nomenclature is an organism name system used in biological classification. Genus and species names, two Latinized nouns drawn from numerous sources, serve as indicators of the species to which the creature belongs.
Who created the current nomenclature for chemical substances?On August 26, 1743, Antoine-Laurent Lavoisier was born in Paris, France. He was a well-known French chemist and a key player in the 18th century chemical revolution. In addition to co-creating the current system for identifying chemical compounds, he established an experiment-based explanation of the chemical reactivity of oxygen.
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2. How many moles of carbon dioxide gas are in 0.667 liters?
0.034 mol of carbon dioxide gas, are there in 0.667 L.
We can assume that the volume of one mole of any gas is 22.4 L we know that the pressure of the gas is 1 atmosphere and that the temperature of a gas is 0C
This type is called standard temperature and pressure (STP).
This can be calculated by using the formula in which we can find the moles:
PV =nRT------(1)
Where P is the pressure
V is volume
T is the temperature in Kelvin
R is the ideal gas constant consistent with the units of volume and pressure.
0.667 L x 1 mol/22.4 L = 0.034 mol
And 0.667 liters of CO2 or any other gas at STP would contain 0.034 moles.
If the gas was at some other temperature or pressure, assuming they were “moderate,” you could calculate the number of moles by solving the following formula for n.
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The chemical equation is balanced correctly.
Which compound is represented by X?
C6H1₂O6(aq)-enzyme2X +2CO₂(g)
A chemical equation is balanced correctly is CH3CH2OH(aq) . The compound is represented by X is CH3CH2OH(aq).
Is ethanol a liquid or aqueous?The chemical formula for ethanol, which is an alcohol, is C2H5OH, where C, H, and O stand for carbon, hydrogen, & oxygen atoms, respectively.The colorless, clear liquid ethanol has a similar appearance to water and is totally miscible with it.
Is HC3CH2OH a weak acid?You virtually ever consider ethanol, CH3CH2OH, to be acidic because of how weakly basic it is.An ethoxide ion is created when the hydrogen-oxygen link dissociates to release an hydrogen ion:This has almost nothing to recommend it.
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a sample of ore containing manganese weighed 1.2354 grams. this sample was heated in a solution of nitric acid, which dissolved the manganese ion producing manganese(iii) nitrate (mn(no3)3). the acidity of the solution was adjusted, and hydrogen sulfide gas was bubbled into the solution producing 0.2876 grams of manganese(iii) sulfide (mn2s3). what is the percentage of manganese in the original sample?
The manganese content of the original sample is approximately 5.09%.
To determine the manganese content of the original sample, we need to know the atomic weight of manganese and the molecular weights of manganese(III) nitrate and manganese(III) sulfide.
Manganese has an atomic weight of 54.94 g/mol.
Manganese (III) nitrate has a molecular weight of 158.03 g/mol Manganese (III) sulfide has a molecular weight of 160.13 g/mol
The first step is to calculate the weight of manganese in manganese(III) nitrate.
0.2876 g manganese (III) sulfide ÷ 160.13 g/mol manganese (III) sulfide = 0.0018 g manganese
The manganese weight of the original sample can then be determined from the manganese weight of manganese(III) sulfide.
0.0018 g manganese ÷ 0.2876 g manganese (III) sulfide = 0.0626 g manganese per 1.2354 g sample
Finally, the weight of manganese in the sample can be used to calculate the percentage of manganese in the sample.
(0.0626 g manganese ÷ 1.2354 g sample) × 100% = 5.09% manganese
Therefore, the manganese content of the original sample is approximately 5.09%.
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if your isolated product has succinimide present, what key feature should be present in the ir spectrum of your product?
if your isolated product has succinimide present, the key feature should be present in the ir spectrum of your product is in the IR spectra should show a prominent peak at around 1700 cm⁻¹,
What is the function of succinimide?These chemicals have several uses. The succinimides ethosuximide, phensuximide, and methosuximide are among the drugs used as anticonvulsants. Succinimide is also used in various assays to create covalent bonds between peptide or protein chains and polymers.
How does succinimide work?Succinimide inhibits voltage-dependent calcium leakage in thalamic neurons by acting on calcium T channels. Any gastrointestinal "vomiting, nausea, or abdominal discomfort." or central nervous system are side effects of ethosuximide (lethargy, dizziness, ataxia).
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identify the catalytic cofactors of the pyruvate dehydrogenase complex. thiamine pyrophosphate fad biotin nad lipoic acid
The catalytic cofactors of the pyruvate dehydrogenase complex are TPP, lipoic acid, and flavin adenine dinucleotide (FAD).
What is lipoic acid?
Lipoic acid (l. a.), also known as α-lipoic acid, alpha-lipoic acid (ALA) and thioctic acid, is an organosulfur compound derived from caprylic acid (octanoic acid).ALA is made in animals generally, and is critical for cardio metabolism.it's also manufactured and is available as a dietary complement in a few countries where it's far marketed as an antioxidant, and is available as a pharmaceutical drug in different international locations. Lipoate is the conjugate base of lipoic acid, and the most universal shape of la beneath physiological situations.Most effective, the (R)-(+)-enantiomer (RLA) exists in nature and is important for aerobic metabolism because RLA is a critical cofactor of many enzyme complexes.To know more about lipoic acid, click the link given below:
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A student determines that a 3.0 g mixture of ZnO(s) and Ag2O(s) contains 0.010 mol of ZnO(s). Based on the student's measurement, what is the mass percent of Zn in the mixture? Choose 1 answer: A B C D 11% 22% 44% 88%
The mass per cent of Zn in the mixture is 22%.
What is Mass percent?Mass percent is a means to describe a component in a specific combination or to convey a concentration. The mass percentage used to describe the solution composition indicates the mass of solute contained in a given mass of solution. The solute's concentration is specified in terms of mass or moles. The mass percent of a solution is calculated by multiplying the grams of solute per gram of solution by 100 to get the percentage.
What are the calculations?mass of the mixture = 3.0 g
moles of ZnO in the mixture = 0.010 mol
mass of ZnO in the mixture = moles × molar mass
= 0.010 mol × 81.38 g/mol
= 0.8138 g
now mass percent of ZnO in the mixture = mass of (ZnO/Total mass) × 100.
27%
now, 81.38 g of ZnO contains = 65.38 g of Zinc.
0.8138 g of ZnO contains = (65.38 / 81.38) × 0.813 g
= 0.6538 g.
so, mass % of Zn in the mixture = (Mass of Zn/ Total Mass) × 100
= (0.6538 g /3 g) × 100
= 22%
Hence, the mass percent of Zn in the mixture is 22%.
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What is a noble gas that is not neon, that has a mass less than 30
Answer: helium
Explanation:
The noble gas that is not neon and has a mass less than 30 is helium.
A noble gas is a group of chemical elements that are odorless, colorless, and non-reactive under normal conditions. They are located in Group 18 (VIII A) of the periodic table and include helium, neon, argon, krypton, xenon, and radon.
Helium is the second lightest element on the periodic table, with an atomic mass of 4.003. It is a colorless, odorless, and tasteless gas that is non-toxic and non-flammable.Helium is the least reactive of all the elements and is often used as a coolant in scientific and medical applications. It is also commonly used in balloons and airships because it is lighter than air.In conclusion, helium is a noble gas that is not neon and has a mass less than 30. It is an important element in science, medicine, and industry, and it has many unique properties that make it useful for a wide range of applications.
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My hypothesis is that the higher the concentration of thiosulphate is the faster the reaction rate is. In the lab, I added HCL to the thiosulphate and recorded the time. Then I had to determine the concentration of thiosulphate and the reaction rate. What are two non-human sources of error?
To solve such this we must know the concept of chemical reaction. Therefore, the rate of reaction increases as the concentration of HCl increases.
What is chemical reaction?Chemical reaction is a process in which two or more than two molecules collide in right orientation and energy to form a new chemical compound. The mass of the overall reaction should be conserved. There are so many types of chemical reaction reaction like combination reaction, double displacement reaction.
The rate of reaction depends on the number of collisions among the reactants and their orientation. As the number of concentration of reactants increases, the number of collisions increases and the rate of reaction also increases.
Therefore, the rate of reaction increases as the concentration of HCl increases.
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Which observations demonstrate that cellular respiration is a chemical reaction?
Select all that apply.
The cellular respiration is a chemical reaction carbon dioxide is one of the product, however it is not a reactant. Therefore, Option A is correct.
What is cellular respiration ?Cellular respiration is the process by which biological fuels are oxidized in the presence of an inorganic electron acceptor such as oxygen to produce large amounts of energy, which is then used to drive ATP production.
Cellular respiration is the process by which oxygen and glucose are converted into water and carbon dioxide. Water and carbon dioxide are byproducts of the process, and ATP is the energy that is produced.
The chemical process by which organic compounds release energy is known as respiration. Exergonic reactions transform the compounds into new ones. Energy is released during the hydrolysis of adenosine triphosphate (ATP) to adenosine diphosphate (ADP) and phosphoric acid (Pi) (it is an exergonic reaction).
Thus, option A is correct.
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PLEASE HELP 100 POINTS!!!! AND GIVING BRAINLIEST!!!!!!!!
Why should a movie producer consider filming a new version of The First Men in the Moon? Create a 6-8 slide multimedia presentation to market your idea for this movie to a production company. Rubric Criteria Points Possible 20 (10) 11-19 (6-9) 6-10 (3-5) 0-5 (0-2) Points Earned Ideas & Content Relates Theme of Novel Provides analysis of character Accurate diagram of plot 20 Establishes a theme, relates an analysis of the protagonist, effectively summarizes the plot, and maintains a clear focus throughout. Establishes a theme, identifies some character traits of the protagonist, provides a summary of the plot, and maintains focus throughout. There are a few lapses in focus, but the theme is fairly clear. Presents somewhat of an analysis of character. The plot summary is mostly correct. It is difficult to figure out the theme of the novel. The character analysis is poor or not present. The plot summary does not accurately represent the story. Organization Structure Precision Focus 20 Strong organization; seamless transitions between ideas; Effective and precise content. Organization is appropriate but conventional; Attempt at a focused and precise sales pitch. Attempts at organization, inappropriate use of lists or bullets; content is unfocused and ideas are not developed No clear organizational framework or transitions. Ideas are vague or unfocused Voice Personality Sense of audience 20 Strong awareness of audience in the design. Students can clearly explain why they felt the vocabulary, audio and graphics chosen fit the target audience. Some awareness of audience in the design. Students can partially explain why they felt the vocabulary, audio and graphics chosen fit the target audience. Some awareness of audience in the design. Students find it difficult to explain how the vocabulary, audio and graphics chosen fit the target audience. Limited awareness of the needs and interests of the target audience. Images and Music Relevance to theme Effectiveness Imagery 10 Images and music stir a rich emotional res
Answer:-Science have researched more facts and cool things about it-It would have more facts and things to learn-The quality would be better and more understandingI just tried 3 quick ideas I hope it can help a bit
Explanation:
Answer:
the answer is you should know this already :)))))))))))))))))))))))))))))))))))))))))))))))))))
what are the values of the nuclear charge z and quantum number n for the least-bound electron in the ground state of li ?
The nuclear charge for Ze is 3e and effective nuclear charge is 1.26e and for the quantum number is 2.
What is ionization energy for an atom?
The ionisation energy is a metric indicating an element's capacity to engage in chemical processes that call for the donation of electrons or the production of ions. It is also often correlated with the type of chemical bonding that occurs when elements combine to form compounds.
I= 13.1×10²Z (eff)/n²
Zeff = √I×n²/13.1ₓ10²
for lithium I = 520.2
Z²eff = 520.2×4/13.1×10²=1.56
Zeff= 1.26 e
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4. Lithium + tin(IV) sulfite ® lithium sulfite + tin-
2Li2S + Sn(SO4)2 → 2Li2(SO4) + SnS2 is Balanced chemical equation.
What is Balanced chemical equation?
A balanced chemical equation is a chemical reaction that has equal numbers of moles of chemical substances both in the reactant and the product side.
A chemical equation is said to be balanced if the quantity of each type of atom in the reaction is the same on both the reactant and product sides.
In a balanced chemical equation, the mass and the change are both equal.
From the missing image that is attached below, we can see that the picture depicts that we have:
The reactant side:
3 molecules of CH₄ and 3 molecules of N₂Cl₄
The product side:
3 molecules of CCl₄, 3 molecules of N₂ and 6 molecules of H₂
Therefore, the balanced chemical equation for the reaction is:
3CH₄ + 3 N₂Cl₄ → 3 CCl₄ + 3N₂ + 6H₂
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the end point in a titration of a 25.00 ml sample of aqueous h2so4 was reached by addition of 33. 87 ml of 0.4500 m naoh. the balanced titration reaction is: 2 naoh h2so4 ---> na2so4 2 h2o what is the molarity of h2so4?
The end point in a titration of a 25.00 mL aq H₂SO₄ was reached by addition of 33. 87 ml of 0.4500 m NaOH. The molarity of H₂SO₄ is 0.3048 M.
The balanced chemical reaction is given as,
2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O
For exact neutralization of Va(mL) of an acid having Molarity Mₐ and basicity Nₐ by V(b) ml of a base having molarity M(b) and acidity N(b).
N(a) M(a) V(a) = N(b) M(b) V(b)
For H₂SOy basicity ,n(a) = 2
For NaOH acidity n(b) = 1
Va (H₂SO₄) = 25.00 mL
Vb (NaOH) = 37.87 mL
Mb (NaOH) = 0.4500M
Ma (H2S04) = ?
Substitute the values to get the value of Ma,
2 × Ma × 25 mL = 1 × 0.4500 M × 33.87 mL
⇒ Ma = (1 × 0.4500 M × 33.87 mL) ÷ 50
⇒ Ma = 0.3048 M
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A researcher studying the nutritional value of a new candy places a 4.20 g
sample of the candy inside a bomb calorimeter and combusts it in excess oxygen. The observed temperature increase is 2.62 ∘C.
If the heat capacity of the calorimeter is 48.10 kJ⋅K−1,
how many nutritional Calories are there per gram of the candy?
The energy that is contained in the candies is 7.2 cal/g.
What is the calorimeter?We know that the calorimeter is a device that can be used to measure the amount of energy that is contained in a substance. We can see that in this case, we have ben told that the the observed temperature increase is 2.62 ∘C. If the heat capacity of the calorimeter is 48.10 kJ⋅K−1.
We now have the heat or the energy that is contained in the candy as;
H = cdT
c = heat capacity of the calorimeter
dT = The temperature change
Hence;
H = 48.10 kJ⋅K−1 * 2.62 ∘C
H = 126 kJ or 30.11 cal
The nutritional Calories are there per gram of the candy;
30.11 cal/4.20 g
= 7.2 cal/g
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draw the organic product formed when 1−hexyne is treated with h2o, h2so4, and hgso4. click the draw structure button to launch the drawing utility.
The organic product formed when 1−hexyne is treated with the H₂O, H₂SO₄ and HgSO₄ is 2 - hexanone.
The reaction of the 1−hexyne is treated with the H₂O, H₂SO₄ and HgSO₄ is given as :
CH₃- CH₂ - CH₂ - CH₂ - C ≡ CH + H₂O / H₂SO₄ / HgSO₄ ----->
1 - hexyne CH₃- CH₂ - CH₂ - CH₂ - CO - CH₃
2 - hexanone
Thus, the when the 1 - hexyne react with the H₂O, H₂SO₄ and HgSO₄ is 2 - hexanone the product is formed is known as the 2 - hexanone. the above is the reaction for the formation of 2 - hexanone.
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a chemist must dilute of aqueous nickel(ii) chloride solution until the concentration falls to . he'll do this by adding distilled water to the solution until it reaches a certain final volume. calculate this final volume, in milliliters. round your answer to significant digits.
The final volume is 15.3 mL, the concentration of solution ,He will accomplish this by gradually adding distilled water to the mixture according to law of equivalence-until it reaches a particular final volume.
According to law of equivalence-
where is initial concentration, is the final concentration, is the initial volume and is the final volume.
Here = 7.27 M, = 12.6 mL, = 6.00 M
So, the final volume is 15.3 mL
The law of equivalence , equivalents of one material will always be equal to the equivalents of the other when two substances react, and the equivalents concentration of any product will always be equal to that of the concentration.
The complete question is:
A chemist must dilute 12.6mL of 7.27 M aqueous sodium nitrate (NaNO3) solution until the concentration falls to 6.00 M.He'll do this by adding distilled water to the solution until it reaches a certain final volume. Calculate this final volume, in milliliters. Be sure your answer has the correct number of significant digits.
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What type of chemical bond holds Ca²+ and O²- together in
CaO?
Answer:
ionic
Explanation:
Since Ca is a metal and O is a non-metal, the bond is ionic.
calculate the amount of heat (in ) required to convert of water to steam at . (the molar heat of vaporization of water is .)
The amount of heat required to convert of water to steam is40.79 kJ/mol. The energy needed to turn 62.6 g of water into steam at 100°C is 141.86 kJ.
The equation is used to represent the formula for determining the necessary quantity of heat; as a result, 141.86 kJ of heat are needed to turn 62.6 g of water into steam at 100°C. Each material has a unique molar heat of vaporization. Kilojoules per mole (kJ/mol) are the units used to measure the molar heat of vaporization. The unit J/g is occasionally employed. In that situation, the term "molar" is dropped in favor of "the heat of vaporization."
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How many joules are needed to change the temperature of 40 g of water from 33 0C to 23 0C?
2. 05 g of an unknown gas at stp fills a 500. Ml flask. What is the molar mass of the gas?.
The molar mass of the unknown gas in the 500 mL flask at stp is 89.7 g/mol
We'll begin by calculating the number of mole of the gas that occupied 500 mL at stp.
Recall at stp:
22400 mL = 1 mole of the gas
Therefore,
500 mL = 500 / 22400 = 0.0223 mole of gas.
Finally, we shall determine the molar mass of the gas. This can be obtained as follow:
Mass of gas = 2 g
mole of gas = 0.0223 mole
Molar mass of gas =?
Molar mass = mass / mole
Molar mass of gas = 2 / 0.0223
Molar mass of gas = 89.7 g/mol
Therefore, the molar mass of the unknown gas is 89.7 g/mol
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Can ya help me know what goes in the blanks
Friction provides the traction you need to walk without slipping. Friction helps in most cases. However, they also offer great resistance to applications. Additionally, about 20% of a car's engine power is used to overcome the frictional forces of moving parts. Let's take a look at some of these factors in the next section. All four types of friction are different from each other. Static friction, for example, is the friction that acts between surfaces when they are at rest against each other. In contrast, sliding friction is the resistance that occurs when two bodies slide over each other.
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The formula h20means
Answer:
water
Explanation:
Why would it not be pratical to use water for a barometer on a regular basis? what other liquid might be a good option?.
Therefore, if you utilise water, you must have a barometer that is 13.534 times the length of a mercury barometer, which may be longer than 11 metres.
Additionally, mercury can reach the same temperature of the atmosphere more quickly than water since it has a lower specific heat than water and is a better heat conductor.
What is Barometer?
Barometer, a tool for calculating atmospheric pressure. A barometer can also be used to determine height because air pressure varies with elevation above or below sea level. Mercury and aneroid barometers are the two primary varieties.
A mercury column whose height can be precisely measured is balanced by atmospheric pressure in a mercury barometer. Mercury barometers are frequently adjusted for the local gravity value and the surrounding temperature in order to boost their accuracy.
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one ball of lead has a volume of 90 cm and a mass of 1,017g. a larger ball of lead has a volume of 250 cm and a mass of 2,825g. complete the calculations and state whether or not the density changes.
The density of the balls, given the masses and volume of each balls did not change
How do I know whether or not the density changes?To Know if there is a change or not, we shall determine the density of both lead balls. Details below:
For the small ball
Mass of small ball = 1017 gVolume of small ball = 90 cm³Density of small ball = ?Density = mass / volume
Density of small ball = 1017 / 90
Density of small ball = 11.3 g/cm³
For the larger ball
Mass of larger ball = 2825 gVolume of larger ball = 250 cm³Density of larger ball = ?Density = mass / volume
Density of larger ball = 2825 / 250
Density of larger ball = 11.3 g/cm³
From the above calculations, we obtained:
Density of small ball = 11.3 g/cm³Density of arger ball = 11.3 g/cm³Thus, we can conclude that the density of the lead balls did not change
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The solubility of slaked lime, Ca(OH)2, in water is 0.185 g/100.0 mL. What volume of 1.60×10-3 M HCl is needed to neutralize 14.5 mL of a saturated Ca(OH)2 solution?
Answer: To determine the volume of 1.60 x 10^-3 M HCl that is needed to neutralize 14.5 mL of a saturated Ca(OH)2 solution, we can first calculate the number of moles of Ca(OH)2 that are present in the solution. We can do this by using the solubility of Ca(OH)2 in water (0.185 g/100.0 mL) and the volume of the solution (14.5 mL):
0.185 g Ca(OH)2 / 100.0 mL * 14.5 mL = 0.026975 g Ca(OH)2
Next, we can use the molar mass of Ca(OH)2 (74.1 g/mol) to convert the mass of Ca(OH)2 to moles:
0.026975 g Ca(OH)2 / 74.1 g/mol = 0.003634 mol Ca(OH)2
Since the reaction between HCl and Ca(OH)2 is a 1:1 mole ratio, we can then determine the number of moles of HCl that are needed to neutralize the Ca(OH)2 by dividing the number of moles of Ca(OH)2 by 1:
0.003634 mol Ca(OH)2 / 1 = 0.003634 mol HCl
Finally, we can use the concentration of the HCl solution (1.60 x 10^-3 M) and the number of moles of HCl that are needed to determine the volume of HCl that is required:
0.003634 mol HCl / (1.60 x 10^-3 M) = 0.0230 L HCl
Therefore, 0.0230 L (or 23.0 mL) of 1.60 x 10^-3 M HCl is needed to neutralize 14.5 mL of a saturated Ca(OH)2 solution.
If I have 2.9 L of gas at a pressure of 5.0 atm and a temperature of 50.0 °C, what will be the temperature of the gas if I decrease the volume of the gas to 2.4 decrease the pressure to 3.0 atm?
According to the ideal gas law, the relationship between the pressure, volume, and temperature of a gas is given by the equation PV = nRT, where P is the pressure of the gas, V is the volume of the gas, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature of the gas in Kelvin.
If we have 2.9 L of gas at a pressure of 5.0 atm and a temperature of 50.0 °C, we can calculate the temperature of the gas if we decrease the volume of the gas to 2.4 and decrease the pressure to 3.0 atm by rearranging the ideal gas law equation as follows:
T = (PV) / (nR)
In this equation, T represents the temperature of the gas, P represents the pressure of the gas, V represents the volume of the gas, n represents the number of moles of gas, and R represents the ideal gas constant.
Plugging in the values from the problem into the equation, we get:
T = (5.0 atm * 2.9 L) / (n * 0.08206 L*atm / mol*K)
T = (14.5 L*atm) / (n * 0.08206 L*atm / mol*K)
T = (14.5 L*atm) / (n * 0.08206 L*atm / mol*K)
T = 177.2 K
Therefore, if we have 2.9 L of gas at a pressure of 5.0 atm and a temperature of 50.0 °C, and we decrease the volume of the gas to 2.4 and decrease the pressure to 3.0 atm, the temperature of the gas will be 177.2 K.
rank the following ionic compounds based on increasing lattice energy. mgo, cacl2, nacl, nabr
The increasing order of lattice energy for the given ionic compounds is NaBr <NaCl< CaCl₂ < MgO.
Ionic compounds refer to compounds comprising of ions that form charged particles when an atom (or group of atoms) gains or loses electrons. A cation is an ion charged positively; an anion is an ion charged negatively. Lattice energy refers to the energy required to convert one mole of an ionic solid into gaseous ionic constituents. Alternatively, it refers to the energy that must be supplied to one mole of an ionic crystal in order to separate it into gaseous ions in a vacuum via an endothermic process. Lattice energy is the energy gap between the energy of the separate gaseous ions and the energy of the ionic solid. Lattice energy increases with decrease in size and increase in charge. Hence, based on this the order of increasing lattice energy is NaBr, NaCl, CaCl₂, and MgO.
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