Answer:
The watch is 40.9 years old.
Explanation:
To know how many years old is the watch we need to use the following equation:
[tex] I_{(t)} = I_{0}e^{-\lambda t} [/tex] (1)
Where:
[tex]I_{(t)}[/tex]: is the brightness in a time t = (1/10)I₀
[tex]I_{0}[/tex]: is the initial brightness
λ: is the decay constant of tritium
The decay constant is given by:
[tex] \lambda = \frac{ln(2)}{t_{1/2}} [/tex] (2)
Where:
[tex]t_{1/2}[/tex]: is the half-life of tritium = 12.3 years
By entering equation (2) into (1) we have:
[tex] I_{(t)} = I_{0}e^{-\lambda t} = I_{0}e^{-\frac{ln(2)}{t_{1/2}}t} [/tex]
[tex] \frac{I_{(t)}}{I_{0}} = e^{-\frac{ln(2)}{t_{1/2}}t} [/tex]
By solving the above equation for "t" we have:
[tex] ln(\frac{I_{(t)}}{I_{0}}) = -\frac{ln(2)}{t_{1/2}}t [/tex]
[tex] t = -\frac{ln(\frac{I_{(t)}}{I_{0}})}{\frac{ln(2)}{t_{1/2}}} = -\frac{ln(\frac{1}{10})}{\frac{ln(2)}{12.3}} = 40.9 y [/tex]
Therefore, the watch is 40.9 years old.
I hope it helps you!
The side of a cube is found to be 127.58 mm and its mass is found to be 7.3 kg. Determine the density of this cube in g/mL.
Answer:
3.5154 g/mL
Explanation:
You will need to use the equation Density = Mass/Volume. You are given mm(can be used to find volume) of a cube and kg(mass). Since your answer is in g and mL we should convert it to those sizes. First we want cm so we will divide the 127.58 mm to cm getting 12.758 cm. We want to cube it since we are finding the whole area of a cube( 12.758*12.758*12.758) which will equal 2076.58 cm^3. We know that 1 mL is equal to 1 cm^3, so we can take our 2076.58 cm^3 and label them as mL(which is what we want). Then we know that there are 1000g in 1 kg, so if we multiply the 7.3 kg, we get 7300g. Finally use the equation Density = Mass/Volume to get your answer. 7300g/2076.58mL = 3.5154 g/mL.
Hope this helps!
(Please someone help me!) (No links!)
Please ignore the blue dot, I accidentally pressed it and won't get rid of it!
Answer:
you picked the right one the net worth of force would be 10
Explanation:
how cuz you got 1 team with 6 force then aother 1 with 4 add em up u get 10
How many molecules are there in an ideal gas with a volume of 7.27 L at STP?
number of molecules:
Answer:
n = 0.324 mol
Explanation:
PV = nRT
STP:
273.15K and 101.325kPa
n = PV/RT
n = (101.325kPa)(7.27L)/(8.314 L kPa/mol K)(273.15K)
n = 0.3243693408 mol
n = 0.324 mol
Hope that helps
calculate the mass percentage of each element in aluminum oxide.Then calculate themass of aluminum in a 3.62 gram sample of of aluminum
1. The mass percentage of each element in aluminum oxide Al₂O₃ are:
i. The mass percent of Al in Al₂O₃ is 52.9%
ii. The mass percent of O in Al₂O₃ is 47.1%
2. The mass of Al in 3.62 g of Al₂O₃ is 1.73 g
1i. Determination of the percentage of Al
Molar mass of Al₂O₃ = (2×27) + (3×16) = 102 g/mol Mass of Al of Al₂O₃ = 2 × 27 = 54 gPercentage of Al =?Percentage = mass / mass of sample × 100
Percentage of Al = (54 / 102) × 100
Percentage of Al = 52.9%
1ii. Determination of the percentage of O
Molar mass of Al₂O₃ = 102 g/mol Mass of O of Al₂O₃ = 3 × 16 = 48 gPercentage of O =?Percentage = mass / mass of sample × 100
Percentage of O = (48 / 102) × 100
Percentage of O = 47.1%
2. Determination of the mass of Al in 3.62 g of Al₂O₃.
102 g of Al₂O₃ contains 54 g of Al.
Therefore,
3.62 g of Al₂O₃ will contain = (3.62 × 54) / 102 = 1.73 g of Al.
Thus, 1.73 g of Al is present in 3.62 g of Al₂O₃.
Learn more about percentage composition: https://brainly.com/question/3940233
Calculate the vapor pressure in torr of a solution containng 24.5 g of glycerin (C3H8O3) in 135 mL water at 30.0* C; the vapor pressure of water at this temperature is 31.8 torr. Assume that glycerin dissolves molecularly (does not dissociate).
50 PTS!!!! No links pls!
What is a title name for Aerobic cellular respiration?
Answer:
Like another name?
Aerobic cellular respiration is also called aerobic metabolism, cell respiration, and oxidative metabolism.
Explanation:
Dentists use a soft, clay-like material to make a filling for a cavity. The filling stays soft under the light of the dentist’s lamp, but it hardens when the dentist shines an ultraviolet flashlight on it. Why does light from the ultraviolet flashlight harden the filling when light from the lamp does not?
Answer:
the clay will be melted by the light
Explanation:
because UV rays are hot but in a way, human skin can not feal pain
1. a Use the valence electron molecular orbital diagram for F2 to propose ground state F2ions that satisfy the following conditions
(1.5 points) (i) A F2 ion that is paramagnetic and that has a non-integer bond order.
(1.5 points) (ii) A F2 ion that is paramagnetic and that has an integer bond order.
(1.5 points) (iii) A F2 ion that is diamagnetic and that has a bond order of 3.
Clearly show the charge on your ion, label all valence molecular orbitals, and show the corresponding electrons in their orbitals. Full calculations for bond orders must be included.
b) Using only the valence electron molecular orbital diagram for F2, is a ground state diamagnetic ion with a bond order of 2 possible? Write one or two sentences to explain why or why not.
What is the shape of SiH2O
Answer:
follow the above attachment.
Explanation:
hope this will help...
Consider a 0.241 M aqueous solution of sodium hydroxide, NaOH.
A. How many grams of NaOH are dissolved in 24.43 mL?
B. How many individual hydroxide ions (OH-) are found in 24.43 mL?
C. How many moles of sulfuric acid, H2SO4, are neutralized by 24.43 mL of 0.241 M NaOH(aq)?
Answer:
a. 0.2355052g
Explanation:
a)
1000ml of NaOH contain 0.241moles
24.43ml of NaOH contain (24.43*0.241)/1000 moles
= 0.00588763moles
Relative Molecular Mass of NaOH
= 1*23 + 1*16 + 1*1
= 40
1mole of NaOH weighs 40g
0.00588763moles weigh (0.00588763*40) g
= 0.2355052g
B)
NaOH -> Na+ + -OH
1 mole of NaOH dissociates to form 1 mole of -OH ions
1 mole of a substance contains 6.02*10^23 particles(atoms)
= 0.00588763 * 6.02 *10^23
= ______ions
Solve for x if 1/2x-3 + 5x/2x+6 =2
Answer:
by which method do you need
Given:
[tex]\to \frac{1}{2x-3} + \frac{5x}{2x+6} =2[/tex]
To find:
x=?
Solution:
[tex]\to \frac{1}{2x-3} + \frac{5x}{2x+6} =2 \\\\[/tex]
Taking lcm:
[tex]\to \frac{2x+6 +5x(2x-3)}{(2x-3)(2x+6)} =2\\\\\to \frac{2x+6 +10x^2- 15x}{(4x^2+ 12x-6x-18)} =2\\\\\to \frac{10x^2- 13x+6}{4x^2+ 6x-18} =2\\\\[/tex]
[tex]\to 10x^2- 13x+6 = 2(4x^2+ 6x-18)\\\\\to 10x^2- 13x+6 = 8x^2+ 12x-36\\\\\to 10x^2- 13x+6 - 8x^2- 12x +36=0\\\\\to 2x^2-25x+42=0\\\\[/tex]
compare the value with the [tex]ax^2+bx+c=0[/tex]:
[tex]\to a=2\\\\\to b= -25\\\\\to c=42\\\\[/tex]
Using formula:
[tex]\to \bold{x=\frac{-b \pm \sqrt{b^2-4ac}}{2a}}[/tex]
[tex]\bold{=\frac{- (-25) \pm \sqrt{(-25)^2-4\times 2 \times 42}}{2 \times 2}}\\\\ \bold{=\frac{25 \pm \sqrt{ 625 - 336}}{4}}\\\\ \bold{=\frac{25 \pm \sqrt{289}}{4}}\\\\ \bold{=\frac{25 \pm 17 }{4}}\\\\ \bold{=(\frac{8}{4} , \frac{42}{4})}\\\\ \bold{=( 2 , \frac{21}{2})}\\\\[/tex]
Therefore, the final answer is "[tex]\bold{(2, \frac{21}{2})}[/tex]".
Learn more about the value x:
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How do ionic and molecular compounds behave in water?
Answer:
When ionic compounds dissolve in water they go through a process called dissociation, splitting into the ions that make them up. However, when you place covalent compounds in water, they typically do not dissolve but form a layer on top of the water.
a. Anna's chemistry class is going to be experimenting with AgNO3 today, which
can stain hands and clothes. Anna is concerned about her jewelry, so as she
gets ready for school, she removes her gold (Au) ring andreplaces it with a
cheaper nickel (Ni) ring. Is this a good idea? Explain your answer. (3 points)
Answer:
No. While gold would not react with a silver nitrate solution, nickel would.
Explanation:
Refer to the metal reactivity series.
Reactivity: [tex]\text{Gold} < \text{Silver} < \text{Nickel}[/tex].
Gold is positioned after silver in the reactivity series, meaning that gold is typically less reactive than silver. Thus, gold would not react with a solution of silver ions to produce silver metal.
However, since nickel is positioned before silver in the reactivity series, it is expected that nickel would react with silver ions in this solution to produce silver metal.
Thus, if the silver nitrate solution comes into contact with the two rings, the nickel ring would likely react with the solution, the gold ring would not.
The metal which burns with a white dazzling flame is:
a) silver
b) magnesium
c) gold
d) aluminum
Answer:
MagnesiumMagnesium burns with a dazzling white flame to form magnesium oxide a powdery mass.
Explanation:
Hope this helps you !!Answer:
b) Magnesium
Explanation:
According to G double O gle, it doesn't react with cold water but reacts to hot water/steam to form magnesium. Hydroxide and Hydrogen gas is released into the air!
A solution is made by combining 15.0 g of potassium chloride with 100 g water at room temperature. What is the concentration of this solution
Answer:
Freezing point depression=2×1.027⋅mol⋅kg−1×1.86⋅K⋅kg⋅mol−1=3.82⋅K .. And so the fusion point of the solution will be −3.8 ∘C .
which change of phase is exothermic
Complete the passage about ionic structures using words from the list
Answer:
see below
Explanation:
1- lattice
2- regular
3- positive
4- negative
5- alternate
6- strong
7- bonds
8- giant
patient requires blood transfusion. what is the next thing to do? discuss
3 useful applications of alkaline earth metals
Answer:
1 used in paint , toothpaste
2 used in fireworks and magnets
3 used to manufacture alloys
If 10.0 kg of water occupies 10.0 liters, what is the volume in quarts?
97.3 FM radio station broadcasts electromagnetic waves at a frequency of 97.3 megahertz (97.6 x 106 Hz). These radio waves travel at a
speed of 3.00 x 108 m/s. What is the wavelength of these radio waves?
*Include your units!
Round your answer to the nearest hundredth (2 decimal places).
The wavelength of the electromagnetic wave at the given frequency is 3.07 meters.
Given the following data:
Frequency =[tex]97.6 \times 10^6\; Hz[/tex]Speed = [tex]3 \times 10^8\;m/s[/tex]To determine the wavelength of the electromagnetic wave at the given frequency:
Mathematically, the wavelength of an electromagnetic wave is calculated by using the formula;
[tex]Wavelength = \frac{Speed }{frequency}[/tex]
Substituting the given parameters into the formula, we have;
[tex]Wavelength = \frac{3 \times 10^8}{97.6\times 10^{6}}[/tex]
Wavelength = 3.07 meters.
Read more on wavelength here: https://brainly.com/question/6352445
calculate the mass of 1 molecule of water and 100 molecules of glucose
Explanation:
Mass of one atom of water = Mass of 1 mole / Avogadro's number
Mass of one atom of water = 18g/mol / 6.022×10²³molecules
Mass of one atom of water = 2.989 × 10^-23 g
Mass of glucose = 180(one molecule)
Mass of 100 molecules of glucose = 180×100 =18000
Sort the sentences based on whether they describe the properties of a heterogeneous or a homogenous mixture.
Answer:
Carbonate Sodium Hydrogen
Which best defines color? (1 point)
a physical property of matter related to how a material interacts with different wavelengths
of light
a chemical property of matter related to how a material interacts with different wavelengths
of light
O a physical property of matter related to a material's ability to reflect light
O a chemical property of matter related to a material's ability to reflect light
Answer:
O a physical property of matter related to a material's ability to reflect light
Explanation:
Color is a physical property of matter.
what is an adaptive organ of duck
Answer:
The adaptive organ of duck is webbed feet.
Explanation:
Duck's webbed feet are designed like paddles to provide more surface area to help them swim.
the webbed feet
Explanation:
Both propane and butane are used as gaseous fuels. Which compound produce more heat per gram burned? (mass of propane (C 3 H 3 )=44.1g/mol. mass of butane (C,H,0)=
58.1g/mol)(10pts)
(Hpropane-103.8kJ/mol.) (H propane-126.0kJ/mol)
Since the heat of combustion of butane is higher than that of propane, butane will produce more heat per gram when burned compared to propane.
The heat of combustion of a compound refers to the heat evolved when one mole of the compound is burnt under standard conditions. This heat of combustion increases from methane upwards.
Since the heat of combustion of alkanes increases according to increasing molar mass, butane will produce more heat per gram when burned compared to propane.
Learn more about heat of combustion: https://brainly.com/question/25312146
Name three sources of atmospheric carbon dioxide.
Answer:
Natural sources include decomposition, ocean release and respiration. Human sources come from activities like cement production, deforestation as well as the burning of fossil fuels like coal, oil and natural gas.
Which of the following best describes the arrangement of particles in a gas?
O The particles are spread apart and can move freely.
O The particles are packed closely together and can move freely.
O The particles are packed closely together and cannot move freely
O The particles are spread apart and cannot move freely.
Answer: The particles are spread apart and can move freely.
Isomers are molecules that have the SAME molecular formula, but their atoms are bonded in a different way. Draw the 5 isomers of cyclopentane, C5H10 using Line Structural Diagrams only.
Answer:
1.methylcyclobutane
2.1-pentene
3.2-pentene(which can be Cis or Trans)
4.1,3-dimethylcyclopropane
5.ethylcylcopropane
I think these are it? I can't think of any other ones.
How/ why does weather "happen," on Earth?
aused by the weight of the huge numbers of air molecules that make up the atmosphere. ... When air pressure is low, air flows together and then upward where it converges, rising, cooling, and forming clouds.
Answer:
Explanation:
The weather events happening in an area are controlled by changes in air pressure. Air pressure is caused by the weight of the huge numbers of air molecules that make up the atmosphere. ... When air pressure is low, air flows together and then upward where it converges, rising, cooling, and forming clouds.
