Answer:
It is an unstable form of a chemical element that releases radiation as it breaks down and becomes more stable.
A pan containing 40 grams of water was allowed to cool from a temperature of 91.0 °C. If the amount of heat released is 1,300 joules, what is the approximate final temperature of the water? 74 °C 78 °C 81 °C 83 °C
Answer:
d. 83 °c
Explanation:
Answer:
D. 83 c
Explanation:
took the test
Doing Labs at home
I’m a junior and I’m staying home for this semester and I have to take chemistry and a lot of my work is Labs but I don’t know how to do them since I don’t have the materials at home to do the labs. Someone please help!!!
Answer:
go get the stuff.
Explanation:
The sum of the number of proteins and neutrons in an atoms nucleus is its __________ ___________.
Answer:
Mass Number
Explanation:
In nuclear physics, the sum of the numbers of protons and neutrons present in the nucleus of an atom.
Please vote brainliest!
Convert 1.36x10 to standard form
Answer:
13.6 is the correct answer written in standard form.
Explanation:
1.36, move the decimal once to the right to get 13.6
Answer:
13.6
Explanation:
The standard form is 13.6
Al2(SO3)3
a. Count the number of Sulfur atom
b. How many total atoms are given in the compound
Please helppp
Answer:
from the words below underline six example of rhetorical patterns
Oil does not dissolve in water because
Explanation:
Oils are made up of long hydrocarbon chains which are non polar. Since water is a polar solvent oil doesn't dissolve in water well.( Polar solutes dissolve in polar solvents and non polar solutes dissolve in non polar solvents) The hydrocarbon chains are hydrophobic.
Use the diagram below to answer 3 questions
Answer:
The element X is sulfur.
Sulfur will gain 2 electrons to become an ion.
The charge of sulfide ion is (2-).
Explanation:
Tristan wraps some gifts and then brings them to the post office where they are delivered to people in different parts of the country. Which organelle is Tristan most like?
Answer:
Tristan wraps some gifts and then brings them to the post office where they are delivered to people in different parts of the country. Which organelle is Tristan most like?
Answer: Tristan is most like the Golgi Body
Explanation:
To what pH should you adjust a standard hydrogen electrode to get an electrode potential of -0.128 V ? (Assume that the partial pressure of hydrogen gas remains at 1 atm.) Express your answer using two decimal places.\
The pH of the standard hydrogen electrode that has electrode potential of -0.128 V is 4.3.
The equation of the hydrogen electrode is;
2H^+(aq) + 2e ⇄ H2(g)
The standard electrode potential of hydrogen is 0.00 V
Using the Nernst equation;
Ecell = E°cell - 0.0592/n log Q
Now;
E°cell = 0.00 V
n = 2
Q = 1/[H^+]
-0.128 = 0.00 - 0.0592/2 log 1/[H^+]
-0.128 = 0.00 - 0.0296 log 1/[H^+]
-0.128 = - 0.0296 log 1/[H^+]
-0.128/ - 0.0296 = log 1/[H^+]
1/[H^+] = Antilog (4.32)
[H^+] = 4.79 × 10^-5
Now;
pH = -log[H^+]
pH = -log (4.79 × 10^-5)
pH = 4.3
Learn more: https://brainly.com/question/11155928
In experiment 9, in one operation, we heat up the alcohol with acid and do a concurrent distillation. What was the purpose of doing this
Answer:
we heat up because the component with lower boiling evaporates first,
leaving the other behind
HELP!! what are the usual products of combustion reactions?
Explanation:
Carbon dioxide and water
I hope it helps
Answer:
The usual products of combustion reactions are carbon dioxide and water.
Explanation:
Combustion reaction is when a substance reacts with oxygen gas, resulting in a release of energy in the form of light and heat. Combustion reactions must have oxygen (O2) as one of the reactants.
How many of sodium (Na) are needed to make 4.5 liters of a 1.5mol/L of Na solution?
Answer:
Explanation:
First you will find the mole from the molarity and then the desired mass from the mole.
A chemical property is a change in _____.
density
physical state
hardness
composition of matter
Answer:
composition of an element
If 38.6 grams of iron react with an excess of bromine gas, what mass of FeBr2 can form?
Answer:
›› FeBr2 molecular weight. Molar mass of FeBr2 = 215.653 g/mol. This compound is also known as Iron(II) Bromide. Convert grams FeBr2 to moles or moles FeBr2 to grams. Molecular weight calculation: 55.845 + 79.904*2 ›› Percent composition by element
Explanation:
If 38.6 grams of iron react with an excess of bromine gas, the mass of FeBr2 can form is 149 grams.
What is mass?Mass is defined as a way to gauge how much matter there is in a substance or thing. The kilogram (kg) is the fundamental SI unit of mass, while lower masses can also be measured in grams (g). Atoms make up everyday matter. A majority of an atom's mass is contained in its nucleus.
Given Fe = 38.6 g.
Fe has a molar mass = 55.845 g/mol.
Given mass/molar mass equals 38.6g/55.845gmol-1, or 0.6912 moles of iron.
The reaction is described as Fe + Br2 FeBr2.
One mole Fe yields 1 mole of FeBr2.
FeBr2 would be produced from 0.6912 moles of Fe.
FeBr2 has a molar mass of 215.65 g/mol.
Moles of FeBr2 x Molar mass of FeBr2
= 215.65 g/mole x 0.6912 mole
= 149.06 g FeBr2 produced is the formula.
Thus, if 38.6 grams of iron react with an excess of bromine gas, the mass of FeBr2 can form is 149 grams.
To learn more about mass, refer to the link below:
https://brainly.com/question/19694949
#SPJ2
Thin-layer chromatography explain ?????
Answer:
Explanation:
Thin-layer chromatography (TLC) is a chromatography technique used to separate non-volatile mixtures. ... After the sample has been applied on the plate, a solvent or solvent mixture (known as the mobile phase) is drawn up the plate via capillary action.
Cesium-137 is part of the nuclear waste produced by uranium-235 fission. The half-life of cesium-137 is 30.2 years. How much time is required for the activity of a sample of cesium-137 to fall to 8.32 percent of its original value
Answer:
la primera va con la última
Determine the reducing agent in the following reaction. Explain your answer. 2 Li(s) + Fe(C2H3O2)2(aq) → 2 LiC2H3O2(aq) + Fe(s)
The reducing agent in the reaction 2Li(s) + Fe(CH₃COO)₂(aq) → 2LiCH₃COO(aq) + Fe(s) is lithium (Li).
The general reaction is:
2Li(s) + Fe(CH₃COO)₂(aq) → 2LiCH₃COO(aq) + Fe(s) (1)
We can write the above reaction in two reactions, one for oxidation and the other for reduction:
Oxidation reactionLi⁰(s) → Li⁺(aq) + e⁻ (2)
Reduction reactionFe²⁺(aq) + 2e⁻ → Fe⁰(s) (3)
We can see that Li⁰ is oxidizing to Li⁺ (by losing one electron) in the lithium acetate (reaction 2) and that Fe²⁺ in iron(II) acetate is reducing to Fe⁰ (by gaining two electrons) (reaction 3).
We must remember that the reducing agent is the one that will be oxidized by reducing another element and that the oxidizing agent is the one that will be reduced by oxidizing another species.
In reaction (1), the reducing agent is Li (it is oxidizing to Li⁺), and the oxidizing agent is Fe(CH₃COO)₂ (it is reducing to Fe⁰).
Therefore, the reducing agent in reaction (1) is lithium (Li).
Learn more here:
https://brainly.com/question/10547418?referrer=searchResultshttps://brainly.com/question/14096111?referrer=searchResults
I hope it helps you!
Using the Kf value of 1.2×109 calculate the concentration of Ni2+(aq) and Ni(NH3)62+ that are present at equilibrium after dissolving 1.47 gNiCl2 in 100.0 mL of NH3(aq) solution such that the equilibrium concentration of NH3 is equal to 0.20 M.
Express your answers in moles per liter to two significant figures separated by a comma.
This problem is describing the equilibrium whereby the formartion of a complex is attained when 1.47 g of nickel(II) chloride is dissolved in 100.0 mL of ammonia so that the latter's equilibium concentration is 0.20 M. Thus, it is asked to calculate the equilibrium concentrations of both nickel(II) ions and that of the complex.
Firstly, we can write out the chemical equation to be considered:
[tex]Ni^{2+}+6NH_3\rightleftharpoons Ni(NH_3)_6^{2+}[/tex]
Next, we can calculate the initial concentration of nickel(II) ions by using the concept of molarity:
[tex][Ni^{2+}]=\frac{1.47gNiCl_2*\frac{1molNiCl_2}{129.6g}*\frac{1molNi^{2+}}{1molNiCl_2} }{0.1000L}=0.113M[/tex]
Afterwards, we set up an equilibrium expression for this chemical reaction:
[tex]Kf=\frac{[Ni(NH_3)_6^{2+}]}{[Ni^{2+}][NH_3]^6}[/tex]
Which can be written in terms of the reaction extent, [tex]x[/tex]:
[tex]Kf=\frac{x}{(0.113-x)(0.2)^6}[/tex]
Now, for the calculation of [tex]x[/tex], we plug in Kf, and solve for it:
[tex]1.2x10^9=\frac{x}{(0.113-x)(0.2)^6}\\\\1.2x10^9=\frac{x}{(0.113-x)(6.4x10^{-5})}\\\\7.68x10^4(0.113-x)=x\\\\x=0.112999 M[/tex]
Which is about the same to the initial concentration of nickel(II) ions because the Kf is too large.
Thus, the required concentrations at equilibrium are about:
[tex][Ni(NH_3)_6^{2+}]=0.113M[/tex]
[tex][Ni^{2+}]=0M[/tex]
Learn more:
https://brainly.com/question/13043707Help !
Student A uses 3N of force to move a cart 5 meters in 10 seconds. Student B uses 6N of force to move the same cart the same distance in 5 seconds. Which student did more work? Which student used more power? Use evidence and explain your answersss
Work = force x distance
Power = work/time
Work is said to be done if the force applied to a body causes the body to move through a distance.
Student B used more work and power
Workdone = Force * Distance
For student A:
Force = 3N
distance = 5meters
Time taken = 10 secs
Workdone by Student A = 3 * 5
Workdone by student A = 15Nm
Power used up = workdone/time
Power used up = 15/10
Power used up = 1.5 Watts
For student B:
Force = 6N
distance = 5meters
Time taken = 5 secs
Workdone by Student A = 6 * 5
Workdone by student A = 30Nm
Power used up = workdone/time
Power used up = 30/5
Power used up = 6 Watts
This shows that student B used more work and power
Learn more here: https://brainly.com/question/6701368
g Consider an ideal atomic gas in a cylinder. The upper part of the cylinder is a moveable piston of negligible weight. The height of the cylinder is 30 cm. The outside pressure is 105 Pa. The temperature of the gas is kept at 250 K throughout the experiment. The volume filled by the gas is 2.0 l. Now assume that solid cylindrical weight with a mass of 3 kg is dropped onto the piston from a height of 10 m. Cylinder and piston have the same diameter. Assume that the kinetic energy of the weight is completely converted into heat transferred into the gas cylinder. Calculate the change of entropy of the gas and of the environment. Please read this text very carefully
A cylindrical weight with a mass of 3 kg is dropped onto the piston from a height of 10 m. The entropy of the gas is 1.18 J/K and the change in the entropy of the environment is -1.18 J/K.
A cylindrical weight with a mass (m) of 3 kg is dropped, that is, its initial velocity (u) is 0 m/s and travels 10 m (s). Assuming the acceleration (a) is that of gravity (9.8 m/s²). We can calculate the velocity (v) of the weight in the instant prior to the collision with the piston using the following kinematic equation.
[tex]v^{2} = u^{2} + 2as = 2 (9.8 m/s^{2} ) (10m) \\\\v = 14 m/s[/tex]
The object with a mass of 3 kg collides with the piston at 14 m/s, The kinetic energy (K) of the object at that moment is:
[tex]K = \frac{1}{2} m v^{2} = \frac{1}{2} (3kg) (14m/s)^{2} = 294 J[/tex]
The kinetic energy of the weight is completely converted into heat transferred into the gas cylinder. Thus, Q = 294 J.
Given all the process is at 250 K (T), we can calculate the change of entropy of the gas using the following expression.
[tex]\Delta S_{gas} = \frac{Q}{T} = \frac{294 J}{250K} = 1.18 J/K[/tex]
The change in the entropy of the environment, has the same value but opposite sign than the change in the entropy of the gas. Thus, [tex]\Delta S_{env} = -1.18 J/K[/tex]
A cylindrical weight with a mass of 3 kg is dropped onto the piston from a height of 10 m. The entropy of the gas is 1.18 J/K and the change in the entropy of the environment is -1.18 J/K.
Learn more: https://brainly.com/question/22655760
A mixture of solids containing a ketone, a carboxylic acid, and an amine, are dissolved in DCM. What is the best way to begin an extraction to separate the amine from the mixture
There are different ways of extraction. The best way to begin an extraction to separate the amine from the mixture is to extract with dilute NaOH.
An acid-base extraction is often used in the extraction of carboxylic acids from the organic layer and thereafter into the aqueous layer.NaOH is known to be the most common compound that is used to convert a carboxylic acid into its more water-soluble ionic carboxylate form.
But if the mixture has a compound that you want, and that can react with NaOH, another milder base such as sodium bicarbonate is preferably used.
See full question below
A mixture of solids containing a ketone, a carboxylic acid, and an amine, are dissolved in DCM. What is the best way to begin an extraction in order to separate the carboxylic acid from the mixture?
A) Extract with dilute NaOH
B) Extract with dilute HCl
C) Extract with dichloromethane
D) Extract with water
Learn more from
https://brainly.com/question/2646724
Pleeeeasee someone who’s good at chemistry?! 10 grade
ASAP
I’ll give points, just help please
Answer:
where is the question????????????
Radio waves bounce off of _____________ before returning to Earth
Answer: ionosphere
Explanation: First it bounces off a top layer of the atmosphere called the ionosphere, then it bounces back to the Earth (this is reflection. It then bounces up again to the ionosphere, and continues bouncing back again until it reaches the radio receiver. This is called a skywave, which works around 3 to 30 MHz.
he hybridization of carbon in diamond is _________. Enter your answer with no superscripts or subscripts, i.e., ab3.
Diamond is composed of hexagonal rings in which sp3 hybridized carbon atoms are linked together.
Hybridization refers to the mixing of atomic orbitals to yield hybrid orbitals that are suitable for bonding. The energy of orbitals that combine to form hybrid orbitals must be close enough for such combination to take place.
Diamond is composed of hexagonal rings in which sp3 hbridized carbon atoms are linked together. Each carbon atom in diamond is tetrahedral.
Learn more: https://brainly.com/question/967776
The mixing of the two different orbitals to form a compound is called hybridization. For example mixing of s and p orbits.
The correct answer is sp3.
The arrangement of the elements in a different manner to form a new compound is called allotropes. For example, diamond and graphite are the allotropes of carbon.
The valence electrons are in p orbitals and p orbit mixed after the s orbitals.
Therefore, the correct answer is sp3
For more information, refer to the link:--
https://brainly.com/question/3523174
At 298 K, the reaction 2 HF (g) ⇌ H2 (g) + F2 (g) has an equilibrium constant Kc of 8.70x10-3. If the equlibrium concentrations of H2 and F2 gas are both 1.33x10-3 M, determine the initial concentration of HF gas assuming you only started with HF gas and no products initially.
This problem is describing the equilibrium whereby hydrofluoric acid decomposes to hydrogen and fluorine gases at 298 K whose equilibrium constant is 8.70x10⁻³, the equilibrium concentrations of all the reactants are both 1.33x10⁻³ M and asks for the initial concentration of hydrofluoric acid which turns out to be 2.86x10⁻³ M.
Then, we can write the following equilibrium expression for hydrofluoric acid once the change, [tex]x[/tex], has taken place:
[tex][HF]=[HF]_0-2x[/tex]
Now, since both products are 1.33x10⁻³ M we infer the reaction extent is also 1.33x10⁻³ M, and thus, we can calculate the equilibrium concentration of HF via the law of mass action (equilibrium expression):
[tex]8.70x10^{-3}=\frac{(1.33x10^{-3} M)^2}{[HF]} }[/tex]
[tex][HF]=\frac{(1.33x10^{-3} M)^2}{8.70x10^{-3}} }=2.03x10^{-4}M[/tex]
Finally, the initial concentration of HF is calculated as follows:
[tex][HF]_0=[HF]+2x=2.033x10^{-4}+2*(1.33x10^{-3})=2.86x10^{-3}M[/tex]
Learn more:
https://brainly.com/question/13043707https://brainly.com/question/16645766WILL GIVE BRAINLEST
Water waves in a small tank are 6.0 cm long. They pass at a given point at a rate of 4.8 waves per second. What is the speed of the wave?
Answer:, Correct option is 0.288m/s
Explanation:
The relationship between the velocity of the wave, its wavelength and frequency is given by the formula
Wavelengthλ=
Frequency(ν)
Speed(v)
,
where, v - velocity of the wave
λ - wavelength of the wave
f - frequency of the wave.
In the question it is given that the frequency is 4.8 Hz and the wavelength is 6.0 cm, that is, 0.06 meters.
The velocity of the sound is calculated as follows.
v=f×λ=4.8 Hz×0.06 m=0.288 m/s
Hence, the speed of the water wave is 0.288 m/s.
the solubility of nitrogen gas is 1.90 mL/dL of blood at 1.00 atm. what is the solubility of nitrogen gas in a deepsea divers blood at a depth of 200 feet and pressure of 7.00 atm
The solubility of nitrogen gas in water is 1.90 mL/dL at 1.00 atm and 13.3 mL/dL at 7.00 atm.
We want to relate the solubility of a gas with its partial pressure.
We can do so using Henry's law.
What does Henry's law state?Henry's law states that the amount of dissolved gas in a liquid is proportional to its partial pressure above the liquid.
C = k × P
where,
C is the concentration of a dissolved gas. k is the Henry's Law constant. P partial pressure of the gas.The solubility of nitrogen gas is 1.90 mL/dL of blood at 1.00 atm.
Since the solvent is basically water, we can understand that the concentration of nitrogen gas is 1.90 mL/dL at 1.00 atm.
We can use this information to calculate Henry's Law constant.
k = C/P = (1.90 mL/dL)/1.00 atm = 1.90 mL/dL.atm
We want to calculate the solubility of nitrogen gas at a pressure of 7.00 atm.
We will use Henry's law.
C = k × P = (1.90 mL/dL.atm) × 7.00 atm = 13.3 mL/dL
The solubility of nitrogen gas in water is 1.90 mL/dL at 1.00 atm and 13.3 mL/dL at 7.00 atm.
Learn more about solubility here: https://brainly.com/question/11963573
solvent extraction explain ???
Answer:
this the partial removal of a substance from a solution or mixture by dissolving it in another immiscible solvent in which it is more soluble.
The boiling point of a substance is tested. After 10 tests, the result is given as 37+/−3°C. Which conclusion can be drawn from this result? (1 point)
The scientists do not need to collect more data because they have narrowed down the range of the results.
The scientists should not report these results until they have the exact number.
The actual boiling point is either 34°C or 40°C.
The actual boiling point is probably between 34°C and 40°C.
Answer:
Explanation:
The actual boiling point is probably between 34C and 40C.
Temperature measures the average kinetic energy of particles of the substances. Therefore, the correct option is option D that is the actual boiling point is probably between 34°C and 40°C.
What is temperature?Temperature is used to measure degree or intensity of heat of a particular substance. Temperature is measured by an instrument called thermometer.
Temperature can be measured in degree Celsius °c, Kelvin k or in Fahrenheit. Temperature is a physical quantity. Heat always flow from higher temperature source to lower temperature source.
We can convert these units of temperature into one another. The relationship between degree Celsius and Fahrenheit can be expressed as:
°C={5(°F-32)}÷9
The actual boiling point is probably between 34°C and 40°C.
Therefore, the correct option is option D.
To know more about temperature, here:
https://brainly.com/question/13694966
#SPJ2
2 nitrogen atoms and five chlorine atoms what compound does that make
Answer:
dinitrogen pentachloride