Answer:
Light waves are electromagnetic waves while sound waves are mechanical waves. light waves are transverse while sound waves are longitudinal. sound waves require a material medium to travel, and hence, cannot travel in a vacuum. the speed of light in a medium is constant.
Explanation:
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if the halo of our falazy is sypherically symmetric what is the mass density
if the halo of our galaxy is spherically symmetric and has a constant mass density, the mass density remains the same at all radii within the halo. This assumption simplifies the calculation, allowing us to consider a uniform mass density throughout the spherically symmetric halo.
If the halo of our galaxy is spherically symmetric, we can make certain assumptions about its mass distribution. Let's consider a simplified model where the halo has a constant mass density throughout its volume.
In this case, the mass density (ρ) represents the amount of mass per unit volume. To calculate the mass density, we divide the total mass of the halo by its volume. However, since we do not have the specific values for the total mass or the volume, we will express the mass density in terms of an equation.
Let's denote the total mass of the halo as M and the volume of the halo as V. The mass density (ρ) is then given by:
ρ = M / V
Since we assume the halo is spherically symmetric, we can use the formula for the volume of a sphere:
V = (4/3)πr³
where r represents the radius of the sphere.
To obtain the mass density as a function of the radius (ρ(r)), we need to find an expression for the total mass (M) in terms of the radius.
Assuming a constant mass density throughout the halo, the mass (M) enclosed within a sphere of radius r is given by:
M = ρ * V = ρ * (4/3)πr³
Substituting this expression for M into the equation for mass density, we have:
ρ(r) = (ρ * (4/3)πr³) / ((4/3)πr³)
Simplifying the equation, we find that the mass density is constant and independent of the radius:
ρ(r) = ρ
Therefore, if the halo of our galaxy is spherically symmetric and has a constant mass density, the mass density remains the same at all radii within the halo. This assumption simplifies the calculation, allowing us to consider a uniform mass density throughout the spherically symmetric halo.
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calculate gibbs free energy at 298k for the reaction of nitrogen and hydrogen to form ammonia if the reaction consists of
The Gibbs Free Energy at 298 K for the reaction of nitrogen and hydrogen to form ammonia is -149.2128 kJ/mol. Since this value is negative, it indicates that the reaction is spontaneous under standard conditions (i.e., at 298 K and 1 atm pressure)
The Gibbs Free Energy is one of the most important thermodynamic functions used to determine whether a chemical reaction is spontaneous or not at a given temperature and pressure. It is represented by the symbol "ΔG" and is defined as the difference between the enthalpy (ΔH) and entropy (ΔS) of a system at a constant temperature and pressure. The formula for Gibbs Free Energy is: ΔG = ΔH - TΔS, where T is the temperature in Kelvin (K).
The reaction of nitrogen and hydrogen to form ammonia can be represented by the following chemical equation: N2(g) + 3H2(g) → 2NH3(g)
To calculate the Gibbs Free Energy at 298 K for this reaction, we need to know the standard enthalpy change (ΔH°) and the standard entropy change (ΔS°) for the reaction. These values can be found in a standard thermodynamic data table or by using Hess's Law to calculate them from known enthalpies of formation.
For this reaction, the standard enthalpy change is -92.2 kJ/mol and the standard entropy change is +191.6 J/mol-K. Therefore, we can calculate the Gibbs Free Energy at 298 K using the formula:
ΔG° = ΔH° - TΔS°
= (-92.2 kJ/mol) - (298 K)(0.1916 kJ/mol-K)
= -92.2 kJ/mol - 57.0128 kJ/mol
= -149.2128 kJ/mol
Thus, the Gibbs Free Energy at 298 K for the reaction of nitrogen and hydrogen to form ammonia is -149.2128 kJ/mol. Since this value is negative, it indicates that the reaction is spontaneous under standard conditions (i.e., at 298 K and 1 atm pressure).
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in a dissolving metal reduction, ammonia serves as_________, and each sodium atom________. as a result, the alkyne is ___________to give an alkene product.
In a dissolving metal reduction, ammonia serves as a solvent, and each sodium atom acts as an electron donor. As a result, the alkyne is reduced to give an alkene product.
Dissolving metal reduction is a technique used to reduce alkynes to alkenes using an alkali metal, such as lithium or sodium, in liquid ammonia. During this process, the alkali metal dissolves in liquid ammonia to produce a deep blue color, which is a result of electrons being released from the alkali metal.
This process results in the formation of an intermediate solution containing free electrons that act as strong reducing agents, which can reduce the alkyne to an alkene. Therefore, in this reaction, ammonia serves as a solvent, while each sodium atom acts as an electron donor, leading to the reduction of the alkyne to form an alkene product.
Finally, we can say that in a dissolving metal reduction, ammonia serves as a solvent, and each sodium atom acts as an electron donor. As a result, the alkyne is reduced to give an alkene product.
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Certain race cars use methanol (CH 3 OH) as fuel. The combustion of 9.8 moles of methanol produces what mass of water?
The combustion of 9.8 moles of methanol will produce 352.8 grams of water.
Stoichiometric calculationFirst, let us look at the balanced equation of combustion of methanol:
[tex]2CH_3OH(l)+3O_2(g)-- > 2CO_2(g)+4H_2O(l)[/tex]
The ratio of number of moles of methanol burned and that of water produced is 1:2.
Thus, 9.8 moles of methanol will produce 19.6 moles of water.
Mass of 19.6 moles water = 19.6 x 18 = 352.8 grams
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calculate the mass of barium in 288mg of barium arsenate, ba3(aso4)2. give your answer in mg.
The mass of barium in 288 mg of barium arsenate (Ba3(AsO4)2) is approximately 0.462 mg.
The molar mass of Ba3(AsO4)2 can be calculated by summing the atomic masses of each element in the compound. The atomic masses are as follows:
Barium (Ba): 137.33 g/mol
Arsenic (As): 74.92 g/mol
Oxygen (O): 16.00 g/mol
Molar mass of Ba3(AsO4)2:
= (3 * 137.33 g/mol) + (2 * (74.92 g/mol + 4 * 16.00 g/mol))
= 411.99 g/mol + 207.84 g/mol
= 619.83 g/mol
Now, we can calculate the mass of barium in 288 mg of barium arsenate using the molar mass and the given mass.
Mass of barium:
= (mass of barium arsenate / molar mass of barium arsenate) * molar mass of barium
= (288 mg / 619.83 g/mol) * 411.99 g/mol
= 0.462 mg
The mass of barium in 288 mg of barium arsenate (Ba3(AsO4)2) is approximately 0.462 mg.
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What statement best explains how life functions a unicellular organism are carried out?
Answer:
The structures in the cell work together to perform its life functions
Explanation:
Answer:
What statement best explains how life functions a unicellular organism are carried out?
Explanation:
1. A sample of oxygen gas has a volume of 150 ml when its pressure is 440 mmHg. If the pressure is
Increased to standard pressure and the temperature remains constant, what will the new volume be?
Answer:86.84
Explanation:
infrared radiation (1580 nm ) express your answer using three significant figures.
The infrared wavelengths of the electromagnetic spectrum encompasses infrared light with an emission wavelength of 1580 nm (nanometers).
The term near-infrared radiation is frequently used to describe it. The infrared light's greater wavelength range is indicated by its wavelength of 1580 nm.
Thermal imaging, remote sensing, and communication systems can all benefit from infrared radiation's capacity to interact with molecular vibrations and permeate certain materials.
Thus, we keep three significant figures by writing the wavelength as 1580 nm in order to accurately describe the value.
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Which of the following is the incorrect IUPAC name of a compound?
A. Pent-3-ene
B. Prop-1-en-2-yne
C. 1-methylpropane
D. All are incorrect.
The IUPAC names of the following organic compounds are correct with the given naming conventions:A. Pent-3-eneB. Prop-1-en-2-yneC. 1-methylpropaneD. All are incorrect - This is the incorrect option because all the given options have correct IUPAC names of the organic compounds. Hence, option D is incorrect.
The International Union of Pure and Applied Chemistry (IUPAC) is an organization that establishes a set of rules for the naming of chemical compounds. This is done to make sure that all scientists in the world use the same names for the same compounds. Therefore, the names should be unique and unambiguous. The IUPAC name of a compound provides information about its molecular structure, functional groups, and substituents. Some of the examples are given below:A. Pent-3-ene - It is a five-carbon molecule with a double bond between the third and fourth carbons. Hence, the name of the compound is pent-3-ene.B. Prop-1-en-2-yne - It is a three-carbon molecule with a triple bond between the first and second carbons and a double bond between the second and third carbons. Hence, the name of the compound is prop-1-en-2-yne.C. 1-methylpropane - It is a three-carbon molecule with one methyl group attached to the first carbon. Hence, the name of the compound is 1-methylpropane.
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exactly 56 grams of iron is mixed with 156 grams of oxygen. the elements are heated and they react. which choice best describes what remains after the reaction is complete?
Iron is the limiting reagent because it is completely used up in the reaction.
option B.
What is the chemical equation for the reaction?The chemical expression for the reaction between iron and oxygen is:
4Fe(s) + 3O₂ (g) 2Fe₂O₃ (s)
The number of moles of iron = mass of Fe/ molecular mass of Fe
The number of moles of Fe = 56 g/ 55.845 g/mol
The number of moles of Fe = 1.002 moles of Fe
The number of moles of oxygen = mass of oxygen/ molecular mass of oxygen
The number of moles of oxygen = 156 g /32 g/mol
The number of moles of oxygen = 4.875 moles of oxygen
Assume that Fe is the limiting reactant, the number of Fe₂O₃ can be calculated as:
moles of Fe₂O₃ = 1.002 mole of Fe × 2 moles of Fe₂O₃/ 4 moles of Fe
moles of Fe₂O₃ = 0.501 mole of Fe₂O₃
Assume that O₂ is the limiting factor, the number of Fe₂O₃ is:
moles of Fe₂O₃ = 4.875 moles of O₂ × 2 moles of Fe₂O₃/ 3 moles of O₂
moles of Fe₂O₃ = 3.25 mole of Fe₂O₃
Thus, after the reaction is complete, Fe and O₂ contain different moles of Fe₂O₃. Only Fe gets consumed in the reaction and it is the limiting factor.
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The complete question is below:
exactly 56 grams of iron is mixed with 156 grams of oxygen. the elements are heated and they react. which choice best describes what remains after the reaction is complete?
a. oxygen is the limiting reagent
b. iron is the limiting reagent
c. both are limiting reagent
d. none is limiting reagent
We are performing the Williamson Ether Synthesis lab
Why is 12 M HCl added to the reaction mixture after the reaction was completed. (Choose all that apply)
To cause the product to precipitate..
To cause the coupling to occur.
To increase the solubility of the product.
To increase the polarity of the solution
To protonate the carboxylate group.
A student uses a-bromoacetic acid instead of a-chloroacetic acid for the reaction. Which statements below are correct? (Choose all that apply)
No change in the rate of the reaction would be observed because it does not depend on the nature of the halogen.
The reaction would be faster because the C-Br bond is weaker than the C-Cl bond.
The reaction would be faster because bromide is a better leaving group.
The reaction would be slower because bromide is a poorer leaving group.
The reaction would be slower because the C-Cl bond is weaker than the C-Br bond.
The correct statements are:
1. The reaction would be faster because bromide is a better leaving group.
2. The reaction would be slower because the C-Br bond is weaker than the C-Cl bond.Therefore, the correct options are B and D.
A student uses a-bromoacetic acid instead of a-chloroacetic acid for the reaction.
The reason why 12 M HCl is added to the reaction mixture after the reaction was completed in the Williamson Ether Synthesis lab is to protonate the carboxylate group of the product, thus causing it to precipitate.
The rate of the reaction is not dependent on the nature of halogen used in the reaction, so option A is incorrect. C-Br bond is weaker than the C-Cl bond, hence option B is correct. Bromide ion is a better leaving group than chloride ion, hence option C is correct.
As bromide ion is a better leaving group, it is easier to remove it from the substrate, and hence, the reaction would be faster. C-Br bond is weaker than C-Cl bond, hence the bond breakage would be easier and the reaction would be faster.
The C-Cl bond is weaker than the C-Br bond, hence the bond breakage would be easier and the reaction would be faster. Therefore, option E is incorrect.
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Deep & Thought Provoking Questions to Ask Yourself (& Others)
When was the last time you tried something new? ...
Who do you sometimes compare yourself to? ...
What's the most sensible thing you've ever heard someone say? ...
What gets you excited about life? ...
What life lesson did you learn the hard way?
Answer:
Am I supposed to answer these on brainly?
Explanation:
you go to the same school as me BAHAHHAHA
Is the following equation balanced or unbalanced?
4 NH4OH + KAI(SO4)2.12H2O → Al(OH)3 + 2 (NH4)2SO4 + KOH + 12 H2O
Balanced
Unbalanced
Burning is a reaction in which oxides are formed by combining ______ and _________.
Answer:
Burning is a reaction in which oxides are formed by combining fuel(reductant) and oxidant.
Explanation: Ex charcoal and lighter fluid
Hope this helps
Sodium phosphate has industrial uses ranging from clarifying crude sugar to manufacturing paper. It is sold as TSP in hardware stores and used in solution to remove boiler scale and to wash painted brick and concrete. What is the pH of a solution containing 33 g of Na PO, per liter? What is the [OH) of the solution? Show your work using units and correct sig. figs. Hints: (i.) Write the equation for the reaction between sodium phosphate and water. (ii.) You'll need the K of the hydrogen phosphate ion, HPO,, to calculate the K, of the phosphate ion, Po.". (iii.) Set up an I.C.E. table to calculate [OH). (iv.) Use the hydroxide ion concentration to determine the hydronium ion concentration and then the pH.
To determine the pH and [OH-] of a sodium phosphate solution, several steps need to be followed. The balanced equation for the reaction between sodium phosphate and water should be written, and the equilibrium constant (K) for the hydrogen phosphate ion (HPO_{4} ^{-2}) should be obtained. Using an I.C.E. table, the [OH-] can be calculated. From there, the hydronium ion concentration ([[tex]H_{3}O^{+}[/tex]]) can be determined, leading to the calculation of the pH.
The balanced equation for the reaction between sodium phosphate (Na_{3}PO_{4}) and water ([tex]H_{2}O[/tex]) can be written as follows:
[tex]Na_{3}PO_{4}[/tex] + H_{2}O ⇌ 3Na+ + [tex]PO_{4} ^{-3}[/tex] + H_{2}O
To determine the equilibrium constant (K) for the hydrogen phosphate ion (HPO_{4} ^{-2}), the K of the dihydrogen phosphate ion ([tex]HPO_{4} ^{-}[/tex]) is needed. This can be found in reference materials. Next, an I.C.E. (Initial, Change, Equilibrium) table can be set up to calculate the concentration of hydroxide ions ([OH^{-}]) in the solution. By knowing the concentration of sodium phosphate, the concentration of PO_{4} ^{-3}can be determined at equilibrium.
From the [[tex]OH^{-}[/tex]], the hydronium ion concentration ([H_{3}O^{+}]) can be calculated using the Kw (ionization constant for water) equation: Kw = [H_{3}O^{+}[OH^{-}] = 1.0 x 10^-14 at 25°C. Finally, the pH can be determined by taking the negative logarithm (base 10) of the [H_{3}O^{+}]. By following these steps, the pH and [OH^{-}] of the sodium phosphate solution containing 33 g of [tex]Na_{3}PO_{4}[/tex] per liter can be calculated using the appropriate units and significant figures.
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Find [H+] of a 0.056 M hydrofluoric acid solution. Ka = 1.45 x 10-7
Answer: [tex][H^+][/tex] of 0.056 M HF solution is [tex]8.96\times 10^{-5}[/tex]
Explanation:
[tex]HF\rightarrow H^+F^-[/tex]
cM 0 0
[tex]c-c\alpha[/tex] [tex]c\alpha[/tex] [tex]c\alpha[/tex]
So dissociation constant will be:
[tex]K_a=\frac{(c\alpha)^{2}}{c-c\alpha}[/tex]
Give c= 0.056 M and [tex]\alpha[/tex] = ?
[tex]K_a=1.45\times 10^{-7}[/tex]
Putting in the values we get:
[tex]1.45\times 10^{-7}=\frac{(0.056\times \alpha)^2}{(0.056-0.056\times \alpha)}[/tex]
[tex](\alpha)=0.0016[/tex]
[tex][H^+]=c\times \alpha[/tex]
[tex][H^+]=0.056\times 0.0016=8.96\times 10^{-5}[/tex]
Thus [tex][H^+][/tex] of 0.056 M HF solution is [tex]8.96\times 10^{-5}[/tex]
Considering the following precipitation reaction:
Pb(NO3)2(aq) + 2KI(aq) → PbI2(s) + 2KNO3(aq)
Which ion(s) would NOT be present in the net ionic equation?
A) Pb2+, NO3-
B) K+, NO3-
C) K+, Pb2+
D) K+, I-
The ion(s) would NOT be present in the net ionic equation will be[tex]Pb^{2+[/tex], [tex]NO^{3-}[/tex]
Option (a) is correct.
To determine which ions would not be present in the net ionic equation, we need to identify the spectator ions. Spectator ions are the ions that do not participate in the chemical reaction and remain unchanged throughout the reaction.
The net ionic equation represents the chemical equation after removing the spectator ions. We can determine the spectator ions by comparing the initial and final compounds and identifying which ions remain the same on both sides of the reaction.
Let's analyze the given reaction:
[tex]Pb(NO_3)_2(aq) + 2KI(aq)[/tex] → [tex]PbI_2(s) + 2KNO_3(aq)[/tex]
The balanced equation shows that [tex]Pb^{2+[/tex] and [tex]2NO_3^-[/tex] ions combine with 2K+ and 2I- ions to form [tex]PbI_2(s)[/tex] and [tex]2KNO_3(aq)[/tex]. In the reaction, the [tex]NO_3^-[/tex]ions are part of both the starting compound [tex](Pb(NO_3)_2)[/tex]and the product compound [tex](KNO_3)[/tex]. Therefore, the [tex]NO_3^-[/tex] ions are spectator ions and would not be present in the net ionic equation.
Now, let's consider the answer choices:
A) [tex]Pb^{2+}, NO_3[/tex]-: [tex]NO_3^-[/tex] ions are spectator ions, so this option is correct.
B) [tex]K+, NO_3[/tex]-:[tex]NO_3^-[/tex] ions are spectator ions, so this option is correct.
C) [tex]K^+, Pb^{2+}[/tex]: Both [tex]K^+[/tex] and [tex]Pb^{2+}[/tex] ions participate in the reaction, so this option is incorrect.
D) [tex]K^+, I^-[/tex]: Both [tex]K^+[/tex] and[tex]I^-[/tex] ions participate in the reaction, so this option is incorrect.
Therefore, the correct answer is:
A) [tex]Pb^{2+}, NO_3^-[/tex]
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Birds have a high internal body ?
Answer:
Yes.
Explanation:
Birds don't look much like humans on the outside. As you might expect, their insides are also different, even though their internal organs carry out the same basic functions human organs carry out.
Which is the term for the different forms of a gene for a given trait?
Answer:
An allele is a variant form of a gene. Some genes have a variety of different forms, which are located at the same position, or genetic locus, on a chromosome. Humans are called diploid organisms because they have two alleles at each genetic locus, with one allele inherited from each parent.
Vinegar is added to baking soda and bubbles of carbon dioxide rapidly form. A cloudy liquid is left behind. What are products in this chemical reaction?
Answer:
When baking soda reacts with vinegar, one of the products produced is the gas carbon dioxide.
Answer:
The product left behind is carbon dioxide.
what are the advantages of using Fahrenheit ?
Answer:
You can better relate to the air temperature.
Explanation:
Fahrenheit gives you almost double the precision of Celsius without having to use decimals.
One of your bike tires has a volume of 18.2 L at temperature of 22.0°C. The temperature rises to 45.0°C when a sudden heat wave hits the DFW area. Calculate the new volume of your tire.
(3 sig figs)
Answer:
New volume = 19.61 L
Explanation:
Given that,
Initial volume, V₁ = 18.2 L
Initial temperature, T₁ = 22°C = 295 K
Final temperature, T₂ = 45°C = 318 K
We neeed to find the new volume of the tire. The relation between volume and temperature is given by :
[tex]V\propto T\\\\\dfrac{V_1}{V_2}=\dfrac{T_1}{T_2}\\\\V_2=\dfrac{V_1T_2}{T_1}\\\\V_2=\dfrac{18.2\times 318}{295}\\\\V_2=19.61\ L[/tex]
So, the new volume of the tire is equal to 19.61 L.
Answer:
19.61
Explanation:
It is easy, the mole is multiples by k and soforth
PLZ HELP!
Are water waves transverse or longitudinal? How do you know? IN YOUR OWN WORDS.
Explanation:
Transverse waves are always characterized by particle motion being perpendicular to wave motion. A longitudinal wave is a wave in which particles of the medium move in a direction parallel to the direction that the wave moves.
5 Facts about cell division
Answer:
Cell division is the process by which a cell, called the parent cell, divides into two cells, called daughter cells.[1] When the cell divides, everything inside it divides also. The nucleus and the chromosomes divide, and the mitochondria divide also.
In mitosis, an ordinary body (somatic) cell divides to make two daughter cells.
In meiosis, a cell divides twice, to produce four gametes (sex cells). The first division of meiosis is a special kind of cell division called a reduction division because the number of chromosomes is halved. The second division of meiosis is similar to mitosis.[2]
Three types of cell division: left is binary fission as in bacteria; right are mitosis and meiosis as in eukaryotes.
Cells are the 'building blocks' of life, and cell division is a basic feature of life. For simple unicellular organisms like Amoebozoa, one cell division reproduces the entire organism. On a larger scale, cell division can create offspring from multicellular organisms, such as plants that grow from cuttings. But most importantly, cell division enables organisms that are able to sexually reproduce to develop from the one-celled fertilised egg (zygote). Cell division also allows for continual renewal and repair of the organism.
The cell division is completed in the four phases prophase, metaphase, anaphase, and telophase.
What is cell division?It is the process by which cells divide into daughter cells. This keeps the cell organism to survive.
The five facts about cell division are:
The cell division has 4 phases.In prophase, the cell DNA condensed to form chromosomes.In metaphase, the chromosomes are aligned in the middle of the cell.In anaphase, the chromosomes move towards the different poles.In telophase cells divide into two daughter cells.Therefore, the cell division is completed in the four phases prophase, metaphase, anaphase, and telophase.
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A voltaic cell with a basic aqueous electrolyte is based on the oxidation of Cd(s) to Cd(OH)2(s) and the reduction of MnO4–(aq) to MnO2(s).
Answer:
See explanation
Explanation:
Oxidation half equation;
3Cd(s) + 6OH^-(aq) ------> 3Cd(OH)2(s) + 6e
Reduction half equation;
2MnO4^-(aq) + 8H^-(aq) + 6e --------> 2MnO2(s) + 4H2O(l)
Balanced reaction equation;
3Cd(s) + 6OH^-(aq) + 2MnO4^-(aq) + 8H^-(aq) ------> 3Cd(OH)2(s) + 2MnO2(s)
Number of electrons transferred = 6
Which claim about the universality of gravity is not supported by evidence?
Answer:
b because i said so
Explanation:
solid liquid and gas is physical or chemical explain
Answer: Physical change
Explanation: I said physical change because its changing the form of the substance and also solid to gas are sublimating
What effect could the pollution of Groundwater have on a nearby River, Lake or Stream?
Answer:
please give me brainlist and follow
Explanation:
Contamination of ground water can result in poor drinking water quality, loss of water supply, degraded surface water systems, high cleanup costs, high costs for alternative water supplies, and/or potential health problems. The consequences of contaminated ground water or degraded surface water are often serious.
Define the law of conservation of charge and provide an example.
Define opposite charges attract and like charges repel and provide an example.
Define Electricity along with an example.
Answer:
Conservation of Charge is the principle that the total electric charge in an isolated system never changes. The net quantity of electric charge, the amount of positive charge minus the amount of negative charge in the universe, is always conserved.