Answer:
friction
Explanation:
Help !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
1.
A) protons and neutronsB) electrons2.
By changing the number of proton.Explanation:
Protons and neutrons are located at the center of an atom which is nucleus .
Electrons will orbit around the nucleus .
Choose the transition metal among the following which has only single ionic charge ?
A. Silver (Ag)
B. Chromium (Cr)
C. Iron (Fe)
D. Copper (Cu)
Please tell what is the answer and if possible explain me...
Answer:
Silver (Ag)
Explanation:
The electronic configuration of copper is shown below;
[Kr]4d10 5s1
We can see that there is only one 5s1 electron. Hence Ag^+ tends to display a pseudo noble gas configuration. This pseudo noble gas configuration explains why silver is prevalent in the +1 oxidation state.
The other transition metals have many stable oxidation states found in nature. Chromium is observed both in +3 and +6 oxidation states. Iron is found in +2 and +3 oxidation states and copper is mostly stable in the +2 oxidation state since the +1 oxidation state readily disproportionate.
Hence silver tends to have only a single ionic charge for reasons aptly stated above.
A first order reaction has rate constants of 4.6 x 10-2 s-1 and 8.1 x 10-2 s-1 at 0ºC and 20ºC, respectively. What is the value for the activation energy?
A.
0.566 J/mol
B.
2.5 x 10-4 J/mol
C.
2260 J/mol
D.
18,800 J/mol
E.
1.76 J/mol
Answer:
D. 18,800 J/mol
Explanation:
We need to use the Arrhenius equation to solve for this problem:
[tex]k=Ae^{\frac{-E_a}{RT}[/tex], where k is the rate constant, A is the frequency factor, [tex]E_a[/tex] is the activation energy, R is the gas constant, and T is the temperature in Kelvins.
We want to find the value of [tex]E_a[/tex], so let's plug some of the information we have into the equation. The gas constant we can use here is 8.31 J/mol-K.
At 0°C, which is 0 + 273 = 273 Kelvins, the rate constant k is [tex]4.6*10^{-2}[/tex]. So:
[tex]k=Ae^{\frac{-E_a}{RT}[/tex]
[tex]4.6*10^{-2}=Ae^{\frac{-E_a}{8.31*273}[/tex]
At 20°C, which is 20 + 273 = 293 Kelvins, the rate constant k is [tex]8.1*10^{-2}[/tex]. So:
[tex]k=Ae^{\frac{-E_a}{RT}[/tex]
[tex]8.1*10^{-2}=Ae^{\frac{-E_a}{8.31*293}[/tex]
We now have two equations and two variables to solve for. We just want to find Ea, so let's write the first equation for A in terms of Ea:
[tex]4.6*10^{-2}=Ae^{\frac{-E_a}{8.31*273}[/tex]
[tex]A=\frac{4.6*10^{-2}}{e^{\frac{-E_a}{8.31*273}} }[/tex]
Plug this in for A in the second equation:
[tex]8.1*10^{-2}=Ae^{\frac{-E_a}{8.31*293}[/tex]
[tex]8.1*10^{-2}=\frac{4.6*10^{-2}}{e^{\frac{-E_a}{8.31*273}} }e^{\frac{-E_a}{8.31*293}[/tex]
After some troublesome manipulation, the answer should come down to be approximately:
Ea = 18,800 J/mol
The answer is thus D.
Find the heat produced from an 8.00 L cylinder of propane gas under 5.00 atm at 25.0 oC, if one mole of propane can produce 2220 kJ.
A. 4290 kJ
B. 0.0289 kJ
C. 877 kJ
D. 1.63 kJ
E. 5420 kJ
F. 1750 kJ
G. 8440 kJ
H. 1360 kJ
I. 37.2 kJ
J. 630 kJ
K. 266 kJ
L. 645 kJ
M. 2420 kJ
N. 7.36 x 10-4 kJ
Answer: 3597 kJ of heat
Explanation:
According to ideal gas equation:
[tex]PV=nRT[/tex]
P = pressure of gas = 5.00 atm
V = Volume of gas = 8.00 L
n = number of moles = ?
R = gas constant =[tex]0.0821Latm/Kmol[/tex]
T =temperature =[tex]25.0^0C=(25.0+273)K=298K[/tex]
[tex]n=\frac{PV}{RT}[/tex]
[tex]n=\frac{5.00atm\times 8.00L}{0.0821 L atm/K mol\times 298K}=1.63moles[/tex]
As it is given :
1 mole of propane produces = 2220 kJ of heat
Thus 1.63 moles of propane produces = [tex]\frac{2200}{1}\times 1.63=3597kJ[/tex]
Thus 3597 kJ of heat is produced
What is the number of moles of solute in 250 mL of a 0.4 M solution?
Answer:
0,1 mol
Explanation:
We know that the formula of concentration is C= moles of solute/ volume
0,4 M= moles of solute/ 250 mL
Convert mL to L 250 mL =0,25 L
0,4 M x 0,25 L= moles of solute
0,1 moles= moles of solute
In the equation E = mc2, E stands for___
m stands for___
and c stands for___
Answer energy,mass,speed of light
Explanation:
Edge
Answer
energy, mass, speed of light
Explanation:
Edge2020
Identify the base in the reaction (CH3)3N(aq) + HCl(aq) → (CH3)3NH+(aq) + Cl−(aq) 1. (CH3)3NH+(aq) 2. Cl−(aq) 3. (CH3)3N(aq) 4. HCl(aq)
Answer:
(CH3)3N(aq)
Explanation:
We have to think of the definition of acid and base in the sense of Brownstead-Lowry. The Brønsted–Lowry theory is an acid–base reaction theory which was proposed independently by Johannes Nicolaus Brønsted and Thomas Martin Lowry in 1923.
A Bronsted-Lowry acid is a chemical species that donates one or more hydrogen ions in a reaction. In contrast, a Bronsted-Lowry base accepts hydrogen ions. When it donates its proton, the acid becomes its conjugate base. A more general approach to the theory is viewing an acid as a proton donor and a base as a proton acceptor.
If we look at the reaction closely, we can see that (CH3)3N(aq) accepted a proton. According to the definition above, we will have to classify (CH3)3N(aq) as a base. Hence the answer.
It is observed that the atoms of hydrogen in gas discharge tube emit radiations whose spectrum shows line characteristics (line spectra). The line spectra of hydrogen lies in three regions of Electromagnetic Spectrum.
Answer: the line Spectra of hydrogen lies between the ultra-violet, visible light and infra-red of the electro magnetic spectrum
Explanation:
Electromagnetic radiation spans an wide range of wavelengths and frequencies. This range is called the electromagnetic spectrum. The electromagnetic spectrum is generally divided into seven regions, in order of decreasing wavelength and increasing energy and frequency. The 7 regions includes; radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV), X-rays and gamma rays.
lower-energy radiation, such as radio waves, is expressed as frequency while microwaves, infrared, visible and UV light are usually expressed as wavelength and finally, higher-energy radiation such as X-rays and gamma rays, is expressed in terms of energy per photon.
Therefore, hydrogen lies between the ultra-violet, visible light and infra-red region of the electro magnetic spectrum.
A sample of SO2 gas occupies 45.6 L at 373 K and 3.45 atm. This sample contains how many moles of oxygen atoms?
Answer:
10.28 mol
Explanation:
S + 2O = SO2
(atm x L) ÷ (0.0821 x K)
(3.45 x 45.6) ÷ (0.0821 x 373)
=5.13726
Then round it to significant figures
=5.14
5.14 mol SO2 x (2 mol O ÷ 1 mol SO2)
=10.28 mol O
The number of moles of oxygen atoms in 5.14 moles of SO₂ gas is equal to 10.28 mol.
What is the ideal gas equation?The ideal gas law is used to describe an equation of the state of an ideal gas. The ideal gas equation can be defined as the product of the volume (V) and the pressure (P) of 1-mole ideal gas is equal to the product of the universal gas constant (R) and absolute temperature.
The ideal gas equation can be expressed in the mathematical form as follows:
PV = nRT
Where n is the moles of a gas, P is the pressure, V is the volume of the gas, and R is the universal gas constant.
Given, the volume of sulfur dioxide, V = 45.6 L
The temperature of SO₂ gas, T = 373 K
The universal gas constant, R =0.082 atmL /K mol
The pressure of the SO₂ gas, P = 3.45 atm
Substituting the values R, V, P, and T in the gas law equation, we get:
The number of moles of sulphur dioxide, n = PV/RT
n = 3.45 ×45.6/(0.082 × 373)
n = 5.14 mol
The number of moles SO₂ gas = 5.14
Moles of oxygen atoms in 5.14 moles of SO₂ = 2 × 5.14 = 10.28 mol
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Please help me. Quickly!!!
Answer:
500
Explanation:
Which balanced equation represents an endothermic reaction?
1.)C+O2-> CO2
2.)CH4+2O2-> CO2+2H2O
3.)N2+3H2-> 2NH3
4.)N2+O2-> 2NO
Answer:
N2+O2-> 2NO
Explanation:
An endothermic reaction refers to a reaction in which heat taken in. This implies that heat is usually absorbed by the reaction system. The enthalpy of reaction for an endothermic reaction is always positive.
The triple bond between two Nitrogen atoms in N2 gas is very strong due to its small size and the triple bond thus the nitrogen molecule has a high dissociation energy. This accounts for the large amount of energy required to break the triple bond between nitrogen atoms in the nitrogen molecule. This causes the oxidation of Nitrogen molecule to NO to be largely endothermic.
A sample of gas occupies 15.0 liters at a pressure of 2.00 atmosphere and a temperature of 300. K. If the pressure is lowered to 1.0 atmosphere and the temperature is raised to 400. K, the volume of the gas sample would be?
Answer:
THE NEW VOLUME OF THE GAS SAMPLE IS 40 L AT 1 atm AND 400 K
Explanation:
Using general gas equation which combines Boyle's and Charles' law, the volume of the gas sample at the new pressure and temperature can be obtained.
P1V1/T1 = P2V2/T2
P1 = Initial pressure = 2 atm
V1 = Initial volume = 15 L
T1 = Initial temperature = 300 K
P2 = Final pressure = 1 atm
T2 = Final temperature = 400 K
V2 = Final volume = unknown
Substituting the values into the equation, we have;
V2 = P1V1T2 / P2 T1
V2 = 2 * 15 * 400 / 1 * 300
V2 = 12 000/ 300
V2 = 40 L
The new volume after the pressure was reduced to 1 atm and the temperature increased to 400 K is 40 L.
The temperature of a gas is 100 K and its volume is 500.0 ml. If the volume increases to 1,000.0 ml,
what is the new temperature of the gas?
Answer:
The new temperature is 200 K.
Explanation:
Charles law gives the relationship between temperature and volume of a gas. It states that volume is directly proportional to temperature such that,
[tex]V\propto T\\\\\dfrac{V_1}{V_2}=\dfrac{T_1}{T_2}[/tex]
We have,
[tex]T_1=100\ K\\\\V_1=500\ mL\\\\V_2=1000\ mL\\\\T_2=?[/tex]
Plugging all the values,
[tex]T_2=\dfrac{V_2T_1}{V_1}\\\\T_2=\dfrac{1000\times 100}{500}\\\\T_2=200\ K[/tex]
So, the new temperature is 200 K.
how do meteror showers happen
Answer:
A meteor shower happens when Earth passes through the path of a comet. When this happens, the bits of comet debris, most no larger than a grain of sand, create streaks of light in the night sky as they burn up in Earth's atmosphere. Bits of debris which enter Earth's atmosphere are called meteors.
What happens to electrons in ionic bonds?
Answer:
Ionic bonding is the complete transfer of valence electron(s) between atoms. It is a type of chemical bond that generates two oppositely charged ions. In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.
Hope this helps :)
A student heats up a metal and finds that its mass increases. The students says “this is because heat has been added.” Explain why this is incorrect.
HELP DUE SOON. WILL GIVE BRAINLIEST
Answer:
The increase in mass is not due to the heating but due to the reaction of the metal with oxygen in air to form an oxide
Explanation:
When a metal is heated in the presence of air, oxygen present in air reacts with the metal to form the oxide of the metal. The mass of this oxide is greater than the original metal by the amount of oxygen added to the metal during the reaction.
The above reaction is known as an oxidation reaction. Generally,
metal M + O2 ---> MO2
What happens to the copper sulphate crystals when they are heated that causes them to change color?
Answer:
Heating the CuSO4. 5H2O crystals causes then to loose the water of crystallisation that is the 5H2O part. It becomes anhydrous copper sulphate. Its colour changes to white from blue.
Which is lower in the food chain a mushroom or a tree
a mushroom
Explanation:
it don't make sense because the tree is not food chain
Answer:
they are both primary producers so i would say they are at the same level, hope this helps
In a chemical equation, which symbol should be used to indicate that a substance is in solution?
(s)
(g)
оооо
(ag)
Answer: In a chemical equation, (aq) should be used to indicate that a substance is in solution.
Explanation:
The chemical reaction is represented by putting the reactants at left side of the arrow and products on the right side of the arrow. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
The liquids are designated by symbol (l) and gases are designated by symbol (g).
In a chemical equation, (aq) should be used to indicate that a substance is in solution.
Answer:
D (aq)
Explanation:
On Edge
why was the hand cream used as a separating agent when the flubber was handled
Answer:
Because you don't want 2 different things mixing together unless their supposed to be mixed together
Explanation:
The hand cream used as a separating agent when the flubber was handled because it is not about 2 different things mixing together unless their supposed to be mixed together.
What is separating agent ?
In chemical separation processes, A separating agent is the heat work added to facilitate the separation of two chemical species. It is contrasted with a mass separating agent, which is any chemical species added to the reaction that facilitates the reaction.
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Rust is what type of Change?
Physical Change
Chemical Change
Answer:
Chemical change
Explanation:
Rust cannot be done without using chemicals.
Answer:
Option B.) Chemical Change
1. Describe the pH scale. (What is the lowest value? Highest value? Neutral value? Which
end is acid? Which end is base?)
Answer:
0 being the lowist 14 being the hieist 0 is the most acidic 14 is the hieist base 7 is nutrol
Explanation:
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
3 examples of electrochemical cell
for ever action forces there is (n) _ forces
Answer:
equal and opposite reaction
Explanation:
for ever action forces there is a equal and opposite forces
so every interaction theres theres a pair of forces acting on each other
this is newtons 3rd law
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what is the molar concentration of 5% acetic acid?
Answer:Vinegar Is 5% Acetic Acid And Its Molarity Is 0.833M.
Explanation:
yes
what would be the final volume when 2.20 M solution is made from 25.0 mL of a 12.0 M solution? plzz show work
Answer:
136.36 mL
Explanation:
Here we have to use the dilution formula
From C1V1= C2V2
Where;
C1= initial concentration of the solution= 12.0 M
C2= final concentration of the solution= 2.20 M
V1 = initial volume of the solution= 25.0 ml
V2= final volume of the solution= ?????
Then recall;
C1V1=C2V2
V2 = C1V1/C2
Substituting values from the parameters given;
V2= 12.0 × 25.0 / 2.20
V2= 136.36 mL
A college student ran out of salt and pepper to season his eggs with. All of the stores he went to was out of salt so he took it upon himself to make his own. He used copper (II) chloride and sodium nitrate to produce copper (II) nitrate and sodium chloride. The equation for this reaction is shown: __CuCl2+ __NaNO3__Cu(NO3)2+ __NaCl. Identify the coefficients by balancing theequation and tell what type of reaction it is. a.1, 2, 1, 2; single replacementb.2, 4, 2, 4, decompositionc.1, 2, 1, 2; double replacementd.1, 2, 3, 4; combustion
Answer:
B
Explanation:
I’m not really great at chemistry but I truly tried my best
A radioactive isotope has a half-life of 10 minutes.
At the start of an experiment, the activity of a sample of this isotope was 800 counts
per second after allowing for background radiation.
Calculate how long it would be before the activity fell from 800 counts per second to
200 counts per second.
Answer: The time for activity to fell from 800 counts per second to 200 counts per second is 20 minutes
Explanation:
Expression for rate law for first order kinetics is given by:
[tex]t=\frac{2.303}{k}\log\frac{a}{a-x}[/tex]
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) for finding the rate constant:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
[tex]t_{\frac{1}{2}}=\frac{0.693}{k}[/tex]
[tex]k=\frac{0.693}{10min}=0.0693min^{-1}[/tex]
b) for activity to fell from 800 counts per second to 200 counts per second.
[tex]t=\frac{2.303}{0.0693}\log\frac{800}{200}[/tex]
[tex]t=20minutes[/tex]
The time for activity to fell from 800 counts per second to 200 counts per second is 20 minutes
Convert 7 mol carbon to grams.
Answer:
84.07grams of carbon in 7 mole of carbon.
Explanation:
7 mol×12.01g/1mol
=84.07g
A double replacement reaction is a reaction in which one element replaces a similar element within a compound
True or false
Answer:
false
Explanation: