King Tut's reign came to an end at 3350 years ago
Further explanationCarbon-14 is a radioactive isotope that can decay. This isotope can be used to determine how long ago an organism died by knowing the ratio from 12C to 14C
Can be formulated
[tex]\tt Nt=No\dfrac{1}{2}^{t/t1/2}[/tex]
Or we can use :
[tex]t=-\frac{1}{\lambda }\text{ln}\left(\frac{{N}_{t}}{{N}_{0}}\right)\longrightarrow t=-\frac{1}{\lambda }\text{ln}\left(\frac{{\text{Rate}}_{t}}{{\text{Rate}}_{0}}\right)[/tex]
The half-life of C-14, 5730 years, so the decay constant :
[tex]\tt \lambda =\dfrac{\text{ln 2}}{{t}_{1\text{/}2}}=\dfrac{0.693}{\text{5730 y}}=1.21\times {10}^{-4}}[/tex]
Assume the initial C-14 activity was 13.6 disintegrations/min/g of C
[tex]\tt t=-\dfrac{1}{\lambda }\text{ln}\left(\dfrac{{\text{Rate}}_{t}}{{\text{Rate}}_{0}}\right)=-\dfrac{1}{1.21\times {10}^{-4}}\text{ln}\left(\dfrac{9.07}{13.6}\right)=\text{3348}\approx 3350~y[/tex]
Which idea was supported by Aristarchus, Copernicus, and Galileo?
The planets have epicycles.
The planets revolve around the Sun.
The stars rotate around the Sun.
The center of the solar system is Earth.
Aristarchus, Copernicus, and Galileo all supported the idea that the planets revolve around the Sun.
The sun is the center of the solar system. All the early astronomers agreed to this fact.
Aristarchus placed the sun at the center of the solar system and postulated the fact that planets rotate in circular orbits around the Sun.
Copernicus in his work published in 1543 also placed the sun at the center of the solar system with Earth and other planets moving around it.
Using the Telescopes he made himself, Galileo also discovered that the sun is at the center of the solar system and planets orbited around the sun and not vice versa.
Therefore; Aristarchus, Copernicus, and Galileo all supported the idea that the planets revolve around the Sun.
Learn more; https://brainly.com/question/931651
Answer:B
Explanation:i said so
calculate the number of atom in 3mode of mg
Answer:
18.066 × 10²³ atoms
Explanation:
Given data:
Number of atoms of Mg = ?
Number of moles of Mg = 3 mol
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
3 mol × 6.022 × 10²³ atoms / 1mol
18.066 × 10²³ atoms
What is the “Island of Stability”?
Answer:
The island of stability is a term from nuclear physics that describes the possibility of elements with particularly stable "magic numbers" of protons and neutrons. This would allow certain isotopes of some transuranic elements to be far more stable than others, that is, decay much more slowly.
Explanation:
Aluminum has density of 2.7g/cm3.
What is the mass of 35 cm3 aluminum in g?
Answer:
density= 2.7 g/cm3
volume= 25 cm3
mass = density× volume
= 35×2.7
= 94.5 g
Compound 1 is a stronger acid than Compound 2 because the anion of Compound 1 is better stabilized by:'
Answer:
See explanation below
Explanation:
This question is incomplete because you are not putting the compounds you are talking here. However, I manage to find this question, and the first image below is the whole question.
Now, According to this question, we have the same compound. The difference between them is that compound 1 has the CO2H in axial direction, while compound 2 has it in equatorial direction.
As they are both, you can easily say that compound 1 is more acidic because the formed anion of CO2H, which is the CO2- is stabilized by hidrogen bonding that is formed between the OH and the CO2H. As you can see, in compound 1 they are both pointing at the same direction so an hydrogen bonding is easily formed, and this gives more stability to thw whole compound, thus, a better acid.
On the contrary, compound 2 has the CO2H in a not so suitable orientation, so the possible hydrogen bonding there cannot be formed, so the anion cannot be stabilized by this force, thus, is less acidic than compound 1.
Hope this helps
Which statement describes the Arrhenius interpretation of acids and bases?
It has a wider range of applications than the Bronsted-Lowry interpretation.
It has a wider range of applications than the Lewis and Bronsted-Lowry interpretatio
It is used in situations that involve bases that do not produce hydroxide ions.
It is limited to situations that involve aqueous solutions or specific compounds.
Answer:
D. It is limited to situations that involve aqueous solutions or specific compounds.
Explanation:
An Arrhenius acid is a substance that increases the concentration of H3O or H+ when dissolved in water. An Arrhenius base is a substance that increases the concentration of OH- when dissolved in water. These definitions tell us that D is indeed limited to situations that involve aqueous solutions or specific compounds, as aqueous means something that's dissolved in water.
A is wrong because the Bronsted-Lowry interpretation has a wider range of applications. Bronsted-Lowry acids and bases don't even need to be aqueous, so it is not limited to just aqueous solutions. They include any substance that can donate or accept a H+.
B is wrong because A is wrong. A and B basically say the same thing, that the Arrhenius interpretation has a wider range of applications than the Bronsted-Lowry interpretation.
C is wrong because the definition of an Arrhenius base is any substance that increases the concentration of OH-, or hydroxide ions. C completely counters this statement.
Here's photo for proof incase you're doubtful of my answer & explanation. Please click the heart if it helped.
Answer:
Which statement describes the Arrhenius interpretation of acids and bases?
❌ A) It has a wider range of applications than the Bronsted-Lowry interpretation.
❌ B) It has a wider range of applications than the Lewis and Bronsted-Lowry interpretations.
❌ C) It is used in situations that involve bases that do not produce hydroxide ions.
✔️ D) It is limited to situations that involve aqueous solutions or specific compounds.I Took Question Test And Have Nice Day.
There are three states of matter: solid, liquid, and gas. is this true or false
Answer:
true
Explanation:
Solid, liquid and gases are the only three States of matter
What's the charge on Ni in the compound NiCi3? *
+1
+2.
+3
- 7
-2.
3
you can't tell
Answer:
+3
Explanation:
Chlorine is anion with a -1 charge. But they are three chlorine atoms.
-1 * 3 = -3
So they have a -3 charge.
So to balance the compound, the nickel has to be a cation with a +3 charge.
-3 + 3 = 0
Furthermore, a chemical bond always has a 0 charge. Remember that.
Hope it helped! Rate my answer a 5 star if correct.
how much potassium bromide will form a saturated solution with 100 grams of water at 40 degrees celsius
Answer:
75.4 g.
Explanation:
Hello there!
In this case, since the solubility stands for the maximum amount of a solute that is completely dissolved in a specific amount of solvent, typically 100 g of water as the universal solvent; we need to take into account that the higher the temperature the higher the solubility for the most of the solids.
In such a way, since the solubility of potassium bromide at 20 °C is 65.3 g per 100 g of water, at 40 °C is 75.4 g per 100 g of water, proving the aforesaid. Therefore, 75.4 g of potassium bromide will form a saturated solution with 100 g of water at 40 °C.
Regards!
One way to account for the mass "lost" in a reaction that involves a gas would be to________.
Answer:
Place the experiments on a scale
Explanation:
If you place two of the same experiments on a scale, and cover one with a cup, the one with the cup will "lose" mass, while the other won't, due to the cup being a "containment field" I guess you could call it.
0.72-mol sample of is put into a 1.00-L vessel and heated. At equilibrium, the vessel contains 0.40 mol of and 0.40 mol of . Calculate the value of the equilibrium constant for the decomposition of to and at this temperature.
Answer:
0.50
Explanation:
A 0.72-mol sample of PCl₅ is put into a 1.00-L vessel and heated. At equilibrium, the vessel contains 0.40 mol of PCl₃(g) and 0.40 mol of Cl₂(g). Calculate the value of the equilibrium constant for the decomposition of PCl₅ to PCl₃ and Cl₂ at this temperature.
Step 1: Calculate the molar concentrations
[PCl₅]i = 0.72 mol/1.00 L = 0.72 M
[PCl₃]eq = 0.40 mol/1.00 L = 0.40 M
[Cl₂]eq = 0.40 mol/1.00 L = 0.40 M
Step 2: Make an ICE chart
PCl₅(g) ⇄ PCl₃(g) + Cl₂(g)
I 0.72 0 0
C -x +x +x
E 0.72-x x x
Step 3: Determine the value of x
Since [PCl₃]eq = [Cl₂]eq = 0.40 M, x = 0.40 M
Step 4: Determine the concentration of PCl₅ at equilibrium
[PCl₅]eq = 0.72-x = 0.72-0.40 = 0.32 M
Step 5: Calculate the equilibrium constant
Kc = [PCl₃] × [Cl₂] / [PCl₅]
Kc = 0.40 × 0.40 / 0.32 = 0.50
Identify the missing particle in the following nuclear equation.
aPlatinum-199
bMercury-198
cMercury-199
dPlatinum-198
Answer:
c
Explanation:
Two bottles of water are touching on a shelf in the refrigerator. The temperature for both is the same. This is known as which of the following?
A.
initial temperature
B.
final temperature
C.
thermal equilibrium
D.
thermal energy
Answer:
C
Explanation:
If there is no heat to transfer from one bottle to the other, then both bottles are at an equilibrium. This just means that they're both on the same thermal energy level.
What is matter? Choose the best answer.
A Anything that is solid
B Anything that takes up space
C Anything that has a fixed volume
D Anything that can be seen
Answer:
B
Explanation:
1- What is the mass of 5.5 mole of sodium?
2- How many moles in 230 grams of water?
3- What is the mass of 4.5 mole of lithium chloride?
4- How many moles in 750 grams of sodium chloride?
Answer:
1. 126.44 or 126.4
2. 12.766 or 12.8
3.190.77 or 190.8
4.12.833 or 12.8
Explanation:
A. Energy is transferred to different forms
B. Energy can be destroyed in different forms
C. Energy is created
D. Energy is released during a combustion
Answer:
A. Energy is transferred to different forms .
Explanation:
Hello!
In this case, we need to consider the law of conservation of mass and energy which states that mass and energy cannot be neither created nor destroyed, just modified; it means we can rule out B. and C. so far.
Moreover, since D. is actually true for combustion reactions because they are used to provide energy in industrial operations, this is not the concern here because a combustion reaction is not considered.
Therefore the correct option is A. Energy is transferred to different forms as the energy provided by Rose is transferred to the pendulum system .
Best regards!
What is the balanced, net ionic equation for the reaction shown below?
Pb(NO3)2(aq) + H2SO4(aq) + PbSO4(s) + 2 HNO3(aq)
The net ionic equation :
Pb²⁺(aq)+SO₄²⁻(aq) ⇒ PbSO₄(s)
Further explanationGiven
Reaction
Pb(NO3)2(aq) + H2SO4(aq) + PbSO4(s) + 2 HNO3(aq)
Required
The net ionic equation
Solution
The equation of a chemical reaction can be expressed in the equation of the ions
In the ion equation, there is a spectator ion that is the ion that does not change (does not react) because it is present before and after the reaction
When these ions are removed, the ionic equation is called the net ionic equation
For gases and solids including water (H₂O) can be written as an ionized molecule
Ionic equation :
Pb²⁺(aq)+ 2NO₃⁻(aq) + 2H⁺(aq)+SO₄²⁻(aq) ⇒ PbSO₄(s) + 2H⁺(aq)+NO₃⁻(aq)
2NO₃⁻(aq) + 2H⁺(aq) ⇒ a spectator ions
The net ionic equation :
Pb²⁺(aq)+SO₄²⁻(aq) ⇒ PbSO₄(s)
The net ionic equation is Pb²⁺(aq)+SO₄²⁻(aq) ⇒ PbSO₄(s)
The given equation is
Pb(NO3)2(aq) + H2SO4(aq) + PbSO4(s) + 2 HNO3(aq)
Writing its ionic equation
Pb²⁺(aq)+ 2NO₃⁻(aq) + 2H⁺(aq)+SO₄²⁻(aq) ⇒ PbSO₄(s) + 2H⁺(aq)+NO₃⁻(aq)
Now the ionic equation contains spectator ions that do not react. They are present in both the reactant and the product. When these ions are removed, the ionic equation is called the net ionic equation.
2NO₃⁻(aq) + 2H⁺(aq) ⇒ a spectator ions
The net ionic equation is:
Pb²⁺(aq)+SO₄²⁻(aq) ⇒ PbSO₄(s)
Learn more:
https://brainly.com/question/19046605
Covalent compounds are formed by the electrostatic attraction between ___ and __
A. Metals and non metals
B. Metals and metals
C. Non metals and non metals
D. Transition metals and metalliods.
Answer:
metals and non metals respectively.
Mass of 2×10^21 number of atoms of an element is 0.4g. What is the mass of 0.5 mole of the element?
Answer:
66.7 g
Explanation:
Number of atoms = 2×10²¹
Mass of 2×10²¹ atoms = 0.4 g
Mass of 0.5 moles of that element = ?
Solution:
1 mole contain 6.022×10²³ atoms
2×10²¹ atoms × 1 mol / 6.022×10²³ atoms
0.33×10⁻² mol
0.003 mol
0.003 mole have mass of 0.4 g
0.5 mol have mass 0.5/0.003×0.4 g = 66.7 g
What is radiative equilibrium?
Answer:
Radiative equilibrium is the condition where the total thermal radiation leaving an object is equal to the total thermal radiation entering it. It is one of the several requirements for thermodynamic equilibrium, but it can occur in the absence of thermodynamic equilibrium.
Answer:
Radiative equilibrium is the condition where the total thermal radiation leaving an object is equal to the total thermal radiation entering it. It is one of the several requirements for thermodynamic equilibrium, but it can occur in the absence of thermodynamic equilibrium.
Hope this helps :)
CH3OCH3 (ether) will dissolve in water because
Select one:
a. polar solutes dissolve in polar solvents.
b. ionic solutes dissolve in polar solvents.
c. polar solutes dissolve in non-polar solvents.
d. ionic solutes dissolve in non-polar solvents.
e. non-polar solutes dissolve in polar solvents.
Answer:
a. polar solutes dissolve in polar solvents.
Explanation:
Polarity is a phenomenon that has to do with the positive and negative electric (ionic) charges of a molecule. A molecule with distinct positive and electric charge is said to be POLAR. However, water is said to be a universal solvent because it dissolves more substances than any other solvent can.
This solvent property of water is a function of its POLARITY. Polar solutes dissolve in polar solvents. Hence, only polar solutes can dissolve in water (a polar solvent). Hence, in this case, CH3OCH3 (ether) will dissolve in water because it is a POLAR molecule/solute.
Chemistry
Definition in your own words
Will check if you got it from online.
Word: Phase change
Answer:
See explanation.
Explanation:
Hello!
In this case, considering the concept of phase change, we understand that it is related how the phases of matter, solid, liquid and gas, are related to each other for a specific substance.
For instance, when going over water, we notice that its most common phase at this atmospheric conditions is the liquid phase; however, if it starts losing energy (being cooled down) its molecules tend to get together and freeze, undergoing a phase change to solid. On the other hand, if heated up, its molecules will be able to get farther to each other and therefore undergo a phase change to gas.
Thus, we can realize that a phase change is also explained molecularly; because when a substance undergo a phase change, its molecules rearrange, according to the addition or removal of energy and therefore get to another phase.
Best regards!
Give me 10 examples of entropy.
Answer:
A campfire is an example of entropy. The solid wood burns and becomes ash, smoke and gases, all of which spread energy outwards more easily than the solid fuel. Ice melting, salt or sugar dissolving, making popcorn and boiling water for tea are processes with increasing entropy in your kitchen.
Explanation:
If this helped you, the please mark me the brainliest.
Select the plant cell
Answer:
Plant cells are the basic unit of life in organisms of the kingdom Plantae. They are eukaryotic cells, which have a true nucleus along with specialized structures called organelles that carry out different functions. ... They also have a cell wall that provides structural support.
list 3 things that make the index contour unique
Answer:
htoybuuo
t857 NJ n8
u. t i ukuo. jl
write a skeletal equation for the following reaction: An aqueous solution of barium nitrate and an aqueous solution of sodium sulfate are mixed together. Then balance the completed chemical equation.
Answer: skeletal equation : [tex]Ba(NO_3)_2(aq)+Na_2SO_4(aq)\rightarrow NaNO_3(aq)+BaSO_4(s)[/tex]
The products are sodium nitrate and barium sulphate.
balanced equation : [tex]Ba(NO_3)_2(aq)+Na_2SO_4(aq)\rightarrow 2NaNO_3(aq)+BaSO_4(s)[/tex]
Explanation:
A double displacement reaction is one in which exchange of ions take place. 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 skeletal equation is:
[tex]Ba(NO_3)_2(aq)+Na_2SO_4(aq)\rightarrow NaNO_3(aq)+BaSO_4(s)[/tex]
The balanced chemical equation is:
[tex]Ba(NO_3)_2(aq)+Na_2SO_4(aq)\rightarrow 2NaNO_3(aq)+BaSO_4(s)[/tex]
What is the percent composition of beryllium (Be) and oxide (O) in BeO? Round
your answer to the nearest whole percentage.
Answer:
[tex]\% Be=36\%\\\\\% O=64\%[/tex]
Explanation:
Hello!
In this case, since the percent compositions of Be and O in beryllium oxide are computed as shown below:
[tex]\% Be=\frac{m_{Be}}{M_{BeO}} *100\%\\\\\% O=\frac{m_{O}}{M_{BeO}} *100\%[/tex]
Since atomic masses are respectively 9.01 and 16.0 g/mol and the molar mass of the compound is 25.01 g/mol, the resulting percent compositions are:
[tex]\% Be=\frac{9.01}{25.01} *100\%=36\%\\\\\% O=\frac{16.0}{25.01} *100\%=64\%[/tex]
Best regards!
What type of electrons are involved in metallic bonding?
A.
Inner shell electrons
B.
Valence shell electrons
C.
D-orbital electrons
D.
D-orbital electrons
how much °f of 35°C ?
help me please
Answer: 95 degrees fahrenheit hope this helps :]
Explanation:
I need help with science. picture attached
Answer:
there is no picture.
Explanation: