Answer:
27.07 gm nine days ago
Explanation:
17.5 = x (1/2)^9/14.3
x = 27.07 gm
Giving BRAINLIEST, please HELP!
Answer:
-65 kJ
Explanation:
To use Hess's Law, you need to combine the equations in a way that results in the desired equation. To add reactants/products, just add the equations and their subsequent heat of reactions. Subtracting reactants/products involves flipping the signs of enthalpies, duplicating reactants/products involves multiplying the coefficients and enthalpies by a desired number.
A + 2B --> C + D
+ B --> 2C + D
------------------------------------
A + 3B --> 3C + 3D
In this case, you only need to add the equations together to get the desired equation. Because you just add the equations, combine each equations' heat of reaction.
(-20 kJ) + (-45 kJ) = -65 kJ
The overall heat of reaction of the desired reaction is -65 kJ.
The process that causes a spark to occur when the discharge wand is close to the Van de Graaff generator is similar to the process that causes lightning to form. Use what you have learned about the tendency of potential energy to decrease to try to explain how lightning occurs.
Answer:
Lighter, positively charged particles form at the top of the cloud. Heavier, negatively charged particles sink to the bottom of the cloud. When the positive and negative charges grow large enough, a giant spark - lightning - occurs between the two charges within the cloud.
Explanation:
Lighter, positively charged particles form at the top of the cloud. Heavier, negatively charged particles sink to the bottom of the cloud.
What is a generator?In electricity generation, a generator is a device that converts motive power (mechanical energy) into electric power for use in an external circuit.
Lightning is an electric current. To make this electric current, a cloud is needed.
When the ground is hot, it heats the air above it. This warm air rises. As the air rises, water vapour cools and forms a cloud. When air continues to rise, the cloud gets bigger and bigger. In the tops of the clouds, the temperature is below freezing and the water vapour turns into ice.
Now, the cloud becomes a thundercloud. Lots of small bits of ice bump into each other as they move around. All these collisions cause a build-up of electrical charge.
Eventually, the whole cloud fills up with electrical charges. Lighter, positively charged particles form at the top of the cloud. Heavier, negatively charged particles sink to the bottom of the cloud.
When the positive and negative charges grow large enough, a giant spark - lightning - occurs between the two charges within the cloud. This is like a static electricity sparks you see, but much bigger.
Hence, the positive and negative charges grow large enough, that a giant spark - lightning - occurs between the two charges within the cloud.
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What is the solubility of CaCl2 at 20°C
Answer:1,01
Explanation:
I’m confused when it comes to chem
Answer:
The chemistry is the brach of science dealing with properties of matter and the changes which the matter undergo
Explanation:
PLEASE MARK ME BRAINLIEST IF MY ANSWER IS CORRECT PLEASE
A solid substance turns directly into a gas. Which term describes this change?
deposition
evaporation
melting
sublimation
Answer:
the correct answer would be D. Sublimation
Explanation:
Sublmation- solid transforming into a gas, skipping the liquid stage.
eveporation- a liquid transformimg into a gas
melting- a solid transforming into a liquid
deposition- the opposite of sublimation
hope this helps
Answer:
D) Sublimination
Explanation:
What is the molarity of a solution with a volume of 2.3 Liters and 9.7 moles?
Answer:
Explanation:
molarity = (moles of solute)/(liters of solution) = 9.7/2.3 = 4.2
What types of elements are involved in the formation of ionic bonds?.
Answer:
Metal and non-metal ions.
Explanation:
Ionic bonds occur between metal and non-metal ions because metals "want" to give up their electrons and non-metals "want" to gain electrons.
Salt and pepper are placed in a jar and the jar is shaken. What has formed?
Answer:
A MIXTURE
Explanation:
No chemical reaction has occurred.... you have just mixed up the two substances togehter.... you have created a MIXTURE
Which property of water helps it maintain a relatively stable temperature?
High specific heat capacity
Low density
Neutral nature
Nonpolar structure
Answer:
High spec heat cap
Explanation:
Specific heat = Q/(m *Tchange)
re-arrange to
Tchange = Heat/(m *spec heat)
this shows that a high spec heat (in the denominator) will require a lot of heat (in the numerator) to change the Temp much
Calcium has an atomic number of 20. An atom of calcium has ____ electrons in its first energy level and ____ electrons in its second energy level.
Lilly took 57% seconds to walk for classroom to library if the distance between the classroom and library was 38 m at what average speed did lily walk m/min
Answer:
2.17 seconds i believe.
Explanation
I took the amount of meters and turned them into feet before dividing the amount of feet by the total amount of seconds it took for her to travel to the classroom library
What is the name of the new technology whereby a glass fiber carries as much information as hundreds of copper wires?
Answer:
Fibre optic technology.
Explanation:
Fibre optic technology, as the name implies, uses light pulses to transmit data via strands of glass or plastic. It's the preferred technology for the government's National Broadband Network (NBN), which offers 100Mbps+ download speeds.
on Part D and E for both of the questions I dont understand what they are asking me.
All they are asking is how much mass of the daughter product is needed and however much of the atomic daughter number. Have a nice day!
what happens when burning matchstick is held near the nitrogen gas jar
Explanation:
No observable change because nitrogen is an inert gas...
Hello people ~
For which of the following is the Hinsberg approach used?
a) Preparation of primary amines
b) Separation of amine mixtures
c) Preparation of tertiary amines
d) Preparation of secondary amines
Answer:
separation of amine mixtures
Explanation:
There are three types of amines
Primary(1°)Secondary (2°)Tertiary(3°)Hinsberg approach is used distinguish between these amines
i need help pls this isnt chemistry btw i just couldnt find science so i had to put that
Answer: 1. 10% is used to live 30% is stored.
2. an educated guess.
Explanation:
Hi!
Can sportive help me with this pls, I’m really bad at chemistry…
I hope someone helps! Have a nice day !
it's 500kg
Explanation:
I did this I hope this helps
Briefly explain the source, harmful effects and physical properties of oxides of
nitrogen.
Answer:
Nitrogen reacts with oxygen to form a number of nitrogen oxides. It exhibits different oxidation states in its oxides, ranging from +1 to +5. Oxides of nitrogen having nitrogen in the higher oxidation state are more acidic than that in lower oxidation state. Nitrogen oxides are critical components of photochemical smog. They produce the yellowish-brown colour of the smog. In poorly ventilated situations, indoor domestic appliances such as gas stoves and gas or wood heaters can be significant sources of nitrogen oxides.
Following are the harmful effects caused by the oxides of nitrogen
Nitrogen oxides causes irritation in mucous membrane.
Large concentrations of Nitrogen oxide causes lungs problems in humans
It causes injuries to vegetation by damaging leaves.
Nitrogen oxide oxidizes Hydrocarbons in the presence of sunlight, which causes eye irritation, asthama attacks, nasal and throat infections.
NO: sharp, sweet-smelling, colourless gas. Melting point: -163.6°C. Boiling point: -151.8°C. Relative Density: 1.04 (air = 1) NO2: reddish-brown gas with irritating odour
The teacher prepares 2.50 liters (l) of a salt solution for a class experiment. how many quarts (qt) are in 2.50 l? (1 l =1.06 qt) 2.17 qt 2.36 qt 2.52 qt 2.65 qt
The teacher prepares 2.50 liters (l) of a salt solution for a class experiment, in this quantity 2.65 quartz are present.
What is conversion factor?Conversion factor is a quantity which will be multiplied or divide with any other measurement for the conversion of that measurement.
Given that quantity of salt solution = 2.50 L
We know that, 1 L = 1.06 qt
Here conversion factor is 1.06 qt/L as it will be multiplied on given measurement to convert into quartz as:
2.50L = 2.50L × 1.06qt/L = 2.65qt
Hence required value is 2.65qt.
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Answer:
2.65 qt
Explanation:
In what order should the options appear so as to correctly reflect the order of clomiphene's mechanism of action
The order which reflect clomiphene's mechanism of action include the following:
Secretion of increased amount of follicle stimulating hormone (FSH) and LH (luteinizing hormone).Growth of the ovarian follicle.Ovulation.What is Ovulation?This is the process in which a mature egg is released from the ovary and clomiphene is a medication which induces it.
This is done by the steps mentioned above so as to ensure mature egg is released for fertilization.
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A linkage between two atoms formed by the sharing of electrons, or attraction is called a.
A covalent bond is formed by the sharing of electrons between 2 atoms.
What is a covalent bond?A covalent bond is a chemical bond that involves the sharing of electron pairs between atoms.
Sharing of electrons forms covalent bonds between the atoms.
These bonds are mainly formed between two similar atoms of electronegativity.
Where ionic bonds are formed by sharing electrons where there is an electronegativity difference between metals and non-metals. Ex. NaCl
Hence, a covalent bond is formed by the sharing of electrons between 2 atoms.
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Determine the molarity of a solution formed by dissolving 3.00 moles of NaCl in enough water to yield 4.00 L of solution. 3.00 M 0.750 M 2.00 M 1.33 M 12.00 M
Taking into account the definition of molarity, the molarity of the solution formed by dissolving 3.00 moles of NaCl in enough water to yield 4.00 L of solution is 0.75 [tex]\frac{moles}{liter}[/tex].
Definition of molarityMolar concentration or molarity is a measure of the concentration of a solute in a solution and indicates the number of moles of solute that are dissolved in a given volume.
The molarity of a solution is calculated by dividing the moles of solute by the volume of the solution:
[tex]Molarity=\frac{number of moles}{volume}[/tex]
Molarity is expressed in units [tex]\frac{moles}{liter}[/tex].
Molarity in this caseIn this case, you know:
number of moles= 3 molesvolume= 4 LReplacing in the definition of molarity:
[tex]Molarity=\frac{3 moles}{4 L}[/tex]
Solving:
molarity= 0.75 [tex]\frac{moles}{liter}[/tex]
Finally, the molarity of the solution formed by dissolving 3.00 moles of NaCl in enough water to yield 4.00 L of solution is 0.75 [tex]\frac{moles}{liter}[/tex].
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Explain the effect of carbon dioxide on the ph of the oceans.
Answer:
When carbon dioxide dissolves in seawater, the water becomes more acidic and the ocean's pH (a measure of how acidic or basic the ocean is) drops.
Explanation:
hope this helps
Write balanced net ionic equations that show the two relevant ionization steps for glycine
Why is the Northern Hemisphere warmer when tilted to the sun?
Answer:
The Sun gives off UV radiation and heat waves, when tilted closer, it is closer to that UV radiation and heat waves.
For example, if you put a heat lamp closer to a rock the rock would get warmer, if you put it further away it would receive less heat therefore making less warmer.
When a Pd-106 nuclide is struck with an alpha particle, a proton is produced along with a new nuclide. What is this new nuclide
When a Pd-106 nuclide is struck with an alpha particle, a proton is produced along with a new nuclide. The new nuclide is Ag-109.
What are alpha particles?Alpha particles (a) are made up of two protons and two neutrons that are tightly bound together.
They are emitted from the nucleus of some radionuclides during alpha decay, a type of radioactive decay.
Thus, the correct option is D, Ag-109.
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If a sample of N2 gas has an initial pressure of 500 Torr and volume of 0.5 L, what will the final volume be if the pressure is increased to 700 Torr?
Answer:
V₂ = 0.4 L
Explanation:
Data:
P₁ (initial pressure) = 500 torrV₁ (initial volume) = 0.5 LP₂ (final pressure) = 700 torrWanted:
V₂ (final volume)Equation:
P₁V₁ = P₂V₂ → V₂ = P₁V₁ / P₂Solution:
V₂ = [tex]\frac{(500 torr)(0.5 L)}{700 torr}[/tex] = 0.3571 L or 0.4 LThe results of a titration experiment were as follows:
# Volume of aqueous NaOH pipetted into the conical flask = 10. 00 mL
# Average volume of dilute HCl added from the burette to reach the endpoint
12. 54 mL
Molarity of the dilute HCI=1. 196 M
(a). Write the chemical reaction equation for the titration reaction.
The equation of the titration of hydrochloric acid and sodium hydroxide is given as:
[tex]NaOH + HCl \rightarrow NaCl + H_2O[/tex]
What is a chemical reaction equation?An equation of a chemical reaction is a way of representing chemical reactions that occur using the symbols or chemical formula of the compounds reacting.
The titration of hydrochloric acid and sodium hydroxide is a chemical reaction which the given equation:
[tex]NaOH + HCl \rightarrow NaCl + H_2O[/tex]
Therefore, the reaction is a neutralization reaction.
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Can someone please help me? I will give brainliest:(
Answer D and B i think if imma be honest
Choose a federal law from the list below.
Clean Air Act
Clean Water Act
Endangered Species Act
Pollution Prevention Act
Research the law using the library and other resources. Write a 500 word report describing the law, who or what it protects, and why it was enacted. Be sure to include when the law was first passed, which groups supported it, which groups opposed it, and any recent modifications. Write your report in the essay box below.
The principal law governing pollution of the nation’s surface waters is the Federal Water
Pollution Control Act, or Clean Water Act. Originally enacted in 1948, it was totally revised by
amendments in 1972 that gave the act its current dimensions. The 1972 legislation spelled out
ambitious programs for water quality improvement that have since been expanded and are still
being implemented by industries and municipalities.
This report presents a summary of the law, describing the statute without discussing its
implementation. Other CRS reports discuss implementation, including CRS Report R42883,
Water Quality Issues in the 113th Congress: An Overview, and numerous products cited in that
report.
The Clean Water Act consists of two major parts, one being the provisions which authorize
federal financial assistance for municipal sewage treatment plant construction. The other is the
regulatory requirements that apply to industrial and municipal dischargers. The act has been
termed a technology-forcing statute because of the rigorous demands placed on those who are
regulated by it to achieve higher and higher levels of pollution abatement under deadlines
specified in the law. Early on, emphasis was on controlling discharges of conventional pollutants
(e.g., suspended solids or bacteria that are biodegradable and occur naturally in the aquatic
environment), while control of toxic pollutant discharges has been a key focus of water quality
programs more recently.
Prior to 1987, programs were primarily directed at point source pollution, that is, wastes
discharged by industrial and municipal facilities from discrete sources such as pipes and outfalls.
Amendments to the law in that year authorized measures to address nonpoint source pollution
(runoff from farm lands, forests, construction sites, and urban areas), which is estimated to
represent more than 50% of the nation’s remaining water pollution problems. The act also
prohibits discharge of oil and hazardous substances into U.S. waters.
Under this act, federal jurisdiction is broad, particularly regarding establishment of national
standards or effluent limitations. Certain responsibilities are delegated to the states, and the act
embodies a philosophy of federal-state partnership in which the federal government sets the
agenda and standards for pollution abatement, while states carry out day-to-day activities of
implementation and enforcement.
To achieve its objectives, the act is based on the concept that all discharges into the nation’s
waters are unlawful, unless specifically authorized by a permit, which is the act’s principal
enforcement tool. The law has civil, criminal, and administrative enforcement provisions and also
permits citizen suit enforcement.
Financial assistance for constructing municipal sewage treatment plants and certain other types of
water quality improvements projects is authorized under Title VI. It authorizes grants to capitalize
State Water Pollution Control Revolving Funds, or loan programs. States contribute matching
funds, and under the revolving loan fund concept, monies used for wastewater treatment
construction are repaid to states, to be available for future construction in other communities.