A. The initial mass of the sample is 6.35
B. The time taken for 0.3 mg of the sample to remain is 66 days
A. Determination of the initial mass of the sample
We'll begin by calculating the number of half-lives that has elapsedHalf-life (t½) = 15 days
Time (t) = 10 days
Number of half-lives (n) =?n = t / t½
n = 10 / 15
n = ⅔Finally, we shall determine the initial mass of the sample.Number of half-lives (n) = ⅔
Amount remaining (N) = 4 mg
Initial amount (N₀) =?[tex]N_0 = N \times {2}^{n} \\ N_0 = 4 \times {2}^{2 \div 3} \\ N_0 = 6.35 \: mg[/tex]
Therefore, the initial mass of the sample is 6.35 mg
B. Determination of the time
We'll begin by calculating the number of half-lives that has elapsedAmount remaining (N) = 0.3 mg
Initial amount (N₀) = 6.35 mg
Number of half-lives (n) =?[tex]{2}^{n} = \frac{N_0}{N} \\ \\ {2}^{n} = \frac{6.35}{0.3} \\ \\ {2}^{n} = 21.167 \\ take \: the \: log \: of \: both \: side \\ log \: {2}^{n} = log \: 21.167 \\ nlog2 = log \: 21.167 \\ divide \: both \: side \: by \: log2 \\ \\ n = \frac{log \: 21.167}{log2} \\ \\ n = 4.4[/tex]
Finally, we shall determine the timeNumber of half-lives (n) = 4.4
Half-life (t½) = 15 days
Time(t) =?t = n × t½
t = 4.4 × 15
t = 66 daysTherefore, it will take 66 days for 0.3 mg of the sample to remain.
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When bacon is cooked, a solid fatty residue remains in the pan after cooling. What can be said about the fat in bacon based on this observation
Answer:
The fatty acids are mostly saturated.
Explanation:
How does a phase change from solid to liquid occur in a substance?(1 point)
Answer:
As heat is added to solid water, the temperature increases until it reaches 0 °C, the melting point. At this point, the phase change, added heat goes into changing the state from a solid to liquid. Only when this phase change is complete, the temperature can increase.
hope this helps
Heat is responsible for the change of phase from solid to liquid state.
A phase change from solid to liquid occur in a substance by heating of that substance because the bonds present between solid particles can be broken down with the help of heat energy.
When the bond is heat at the temperature on which it is broken down, the solid particles are converted into liquid substance so we can conclude that heat is responsible for the change of phase from solid to liquid state.
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A bar of copper (Copper = 0.385 J/g.°C) and a bar of aluminum (Aluminum = 0.897 J/g.°C) have the same mass. Which requires more energy to increase the temperature from 20°C to 30 °C?
Answer:
Aluminum
Explanation:
......................
Answer:
preciate you
Explanation:
The table below gives the atomic mass and relative abundance values for the three isotopes of element M.
Relative abundance (%) Atomic mass (amu)
78.99 23.9850
10.00 24.9858
11.01 25.9826
What is the average atomic mass (in amu) of element M?
2.86
5.36
24.30
24.98
Answer:
24.30
Explanation:
Multiply the relative abundance by the atomic mass of each isotope, add the results together, and divide by 100. Then round to the correct amount of significant figures.
(78.99 x 23.9850) + (10.00 x 24.9858) + (11.01 x 25.9826)/100
24.30 is the average atomic mass (in amu) of element M.
What is an atomic mass?Atomic mass is the quantity of matter contained in an atom of an element.
Multiply the relative abundance by the atomic mass of each isotope, add the results together, and divide by 100. Then round to the correct amount of significant figures.
(78.99 x 23.9850) + (10.00 x 24.9858) + (11.01 x 25.9826)
2430.501576 ÷ 100
24.30
Hence, 24.30 is the average atomic mass (in amu) of element M.
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Methods used to separate heterogeneous mixtures include the following: check all that apply. *
Decanting
Filtration
Sifting
Answer:
Filtration, Sifting and Decanting
Explanation:
Heterogenous mixtures can be seperated by filtration and sifting (Also known as sieving). Sifting is the process of parting a mixture using a sieve. Sifting is used to separate solid mixtures that contain molecules of varying sizes. Filtration is the process of separating a liquid from an insoluble solid. A common example is using a funnel and a coffee filiter to seperate the liquide from the insoluable solid. Although there are many other methods for filtration. You can also separate mixtures by decantation. Decantation is the process of separating a liquid from a solid/liquid by removing the liquid layer at the top from the layer of solid/liquid below.
how can you keep a cold drink cold without ice or a refrigerator
Answer:
snow and a cooler
Explanation:
so if its really cold out side put your drink out there.
Why do some experiments blow up?
Answer:
because of chemical reactions
Answer:
gases expand rapidly because their particles move at high speeds in all directions
When a substance changes from a solid to a liquid, is a new substance made?
Answer:
no
Explanation:
it means melting or fusion so yhe answer is no
A substance changes from a solid to a liquid no its is not the formation of new substance. It is the change of state of the matter.
What are the states of matter?The states of matter can be defined as one of the several configurations in which matter can exist.
There are basically three states of matter.
Solid - It is defined as hard, distinct in volume and shape. Atoms and molecules are joined together to form solids.Liquid - It is defined as defined volume with the ability to flow and change shape. Atoms and molecules are only weakly bound together in liquids.Gases - It is defined as no clear shape or volume.Thus, a substance changes from a solid to a liquid no its is not the formation of new substance. It is the change of state of the matter.
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A sample of a gas in a 4L container at 300K has a pressure of 1 atm. If the
temperature is increased to 600K and the volume is decreased to 2L , the
pressure is likely to be closest to which of the following? *
O 0.5 atm
1 atm
4 atm
2 atm
The final pressure of the gas in the container is 4 atm
From the question given above, the following data were obtained:
Initial volume (V₁) = 4 L
Initial temperature (T₁) = 300 K
Initial pressure (P₁) = 1 atm
Final temperature (T₂) = 600 K
Final volume (V₂) = 2 L
Final pressure (P₂) =?Using the combine gas equation, we can obtain the final pressure of the gas as illustrated below:[tex]\frac{P_{1} V_{1} }{T_{1}} = \frac{P_{2} V_{2}}{T_{2}}\\\\\frac{1 * 4}{300} = \frac{P_{2} * 2}{600} \\\\[/tex]
Cross multiply
300 × 2 × P₂ = 4 × 600
600 × P₂ = 2400
Divide both side by 600
[tex]P_{2} = \frac{2400}{600} \\\\[/tex]
P₂ = 4 atmTherefore, the final pressure of gas is 4 atm.
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most transition metal ions contain partially occupied ________ subshells.
How to find formula for ionic compounds.
Answer:
I am using an example for this in this table it works for any other compound as well.
Describe how the suspects used the chemicals found at the crime scene to make the copper coins look silver.
The chemicals found at the crime scene although not mentioned must be Sodium zincate.
Discussion:
An interesting demonstration to show plating and alloys is the conversion of copper coins to silver look-alike coins.
A 'copper' coin when dipped into a solution of sodium zincate in contact with zinc. The coin is plated with zinc and appears silver in colour.
This is a common chemistry classroom trick.
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An unknown element sample has 2 isotopes present. The first isotope has a mass of 6.017 amu and is
7.30% abundant. The second has a mass of 7.018 amu and an abundance of 92.7%. Calculate the
average atomic mass of this element
Answer:
Calculating Atomic Mass
Change each percent abundance into decimal form by dividing by 100. Multiply this value by the atomic mass of that isotope. Add together for each isotope to get the average atomic mass.
Explanation:
have a nice day
in hydrogen iodide __________________ are the most important intermolecular forces.
Answer:
dipole-dipole forces
Explanation:
The important intermolecular force in hydrogen iodide HI is dipole- dipole forces. This force is arising due to the partial charge separation and permanent dipole moment.
What is dipole-dipole force?There are various intermolecular forces which binds two atoms chemically to form a compound. Ionic bonding, covalent bonding, dipole -dipole force, hydrogen bonding, Van der Waals force etc are some of them.
Dipoles are opposite charges separated by a small distance. Dipole -dipole force is generated between the atoms when they have partial charge separation and this creates a permanent dipole moment.
Hydrogen is an electropositive atom and iodine is slightly electronegative. This difference in electronegativities leads to the bonded electrons more attracted towards iodine result in partial charge separation and dipole-dipole force.
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doy CORONITA a quien me ayude rapido que es un examen porfaaa
Answer:
thank you for the points
los hermanos Ana Victoria y José Leonardo están patinando en el hielo, con 25 y 20 kg respectivamente de masa, si Victoria empuja a Leo y este sale despedido con una aceleración de 2 m/s²
calcula la aceleración con que retrocede la niña, suponiendo que los patines no ofrecen resistencia al movimiento
Utiliando las leyes de Newton encontraremos que la aceleración de Ana es -1.6 m/s^2.
La segunda ley de Newton dice que:
F = m*a
Fuerza es igual a masa por aceleración.
La tercera ley de Newton dice que cuando dos objetos interactuan, cadan objeto ejerce una fuerza de igual magnitud pero opuesta direccion en el otro.
Ahora veamos como aplicar esto.
Sabemos que la niña empuja al niño, asumamos que con una fuerza F.
Tendremos entonces la ecuación:
F = 20kg*(2m/s^2) = 40N
Y por la tercer ley de Newton, esta misma fuerza (pero en opuesta dirección) se aplica a la niña, entonces tendremos:
-40N = 25kg*a
-40N/25kg = a = -1.6 m/s²
La aceleración con la que retrosede la niña es -1.6 m/s²
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Be + O2 --> BeO
Balance this and what's the type of reaction?
Answer:
2Be + O2 = 2BeO
its a synthesis
Explanation:
True of False: The 8-Step Problem Solving Process was developed as an intended expansion of OODA Loop.
The 8-Step Problem Solving Process is vital to solving problems in an organized way and it's an extended form of OODA Loop. Therefore, it's logically true.
The 8-Step Problem Solving Process include the following:
Defining the problem.Clarifying the problem.Defining the goals.Identification of the root cause of the problem.Development of an action plan.Executing action plan.Evaluating the results.Continuous improvement.It should be noted that the 8-Step Problem Solving Process was developed as an intended expansion of the OODA Loop. Therefore, the statement is true.
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Which of the following are needed to calculate the percent yield? Select all that apply. Question 10 options: Theoretical yield Actual yield Excess yield Limiting yield
Both theoretical and actual yields would be needed to calculate percent yield.
The percent yield of a reaction is defined as the ratio of the actual yield to that of the theoretical yield. It can be mathematically expressed as:
percent yield = actual yield/theoretical yield x 100%
The actual yield is the amount of a specific product produced from a reaction while the theoretical yield is the stoichiometric amount of the same product.
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An alpha particle is equivalent to the nucleus of an atom of which element?(1 point)
A hydrogen
B helium
C nitrogen
D carbon
ill mark brainliest!!!
Answer: An alpha-particle is identical to the nucleus of a normal (atomic mass four) helium atom i.e. a doubly ionised helium atom. Alpha particles (also termed alpha radiation or alpha rays) was the first nuclear radiation to be discovered, beta particles and gamma rays were identified soon after.
Answer: D. Carbon
Explanation: Because I said so.
Hope this helps.
what is the answer ??z???????
Answer:
I think its Female
Explanation:
Correct me if I was wrong :)
Answer: The answer to this question about the given multiple choices about filling the blank with a missing word in order for you to complete the given statement is "Chest broadens, hips broaden and becomes the rounders. These characters are in the females."
Explanation: I chose B) "Females" for the correct answer in order to fill in the blank with a missing word for you to complete the given statement, so here's the completed statement again, "Chest broadens, hips broaden and becomes the rounders. These characters are in the females.".
I hope my answer with the given multiple choice answer and the given explanation is very helpful to your own chemistry question about the given multiple choices about filling the blank with a missing word in order for you to complete the given statement, please mark me as Brainliest and have a great day! :D
Sincerely,
Jason Ta,
The ambitious of Brainly and the role of The TDSB and WHCI Student of the high school.
which of the following statements about this reaction is true:
CH4+2O2-->CO2+2H2O+Heat
A. The reaction releases heat.
B. heat is absorbed by the reaction.
C. the reaction consumes water.
D.The reaction releases oxygen.
Explanation:?
[tex]▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪[/tex]
The Correct statement is ~
A. The reaction releases heatAs we can observe, there's heat in product side of the given equation that shows - In the given reaction heat is released making it an exothermic reaction ~
I hope it helps ¡
[tex]\mathrm{✌TeeNForeveR✌}[/tex]
What does it mean when an element turns into an ion?.
Answer:
When a neutral atom gains one or more electrons, the number of electrons increases while the number of protons in the nucleus remains the same. The result is that the atom becomes an anion—an ion with a net negative charge.
Explanation:
Why can Marco hear the music, even though he is not in the same room as the speaker?
Answer:
Sound Travels
Explanation:
Sound waves can travel, and that makes it so that even though Marco is in a different room, he can hear the music. Depending how loud the music is and how thick the walls car, the sound can travel through the walls.
The energy released by a nuclear fusion reaction is produced when
1. energy is converted to mass
2. mass is converted to energy
3. heat is converted to temperature
4. temperature is converted to heat
Answer:
2
Explanation:
energy produced in nuclear fusion or even fission is due to mass defect and it can be calculated by Einstein equation e=mc2
The statement, that describes energy released by a nuclear fusion reaction is produced is "mass is converted to energy."
What is nuclear fusion?Nuclear fusion is the process by which two light atomic nuclei merge to produce a single heavier one, releasing huge quantities of energy in the process.
A fusion reaction occurs when two light nuclei combine to form a single heavy nucleus. Because the overall mass of the resulting single nucleus is smaller than the mass of the two initial nuclei, the process releases energy.
That is, nuclear energy refers to the energy released as a result of mass loss during the nuclear fusion processes. Both of these processes transform mass loss into energy in accordance with Einstein's mass-energy ratio, E = [tex]mc^{2}[/tex]. As a result of the fusion reaction, mass is destroyed and energy is released.
Hence, the correct answer is 2.
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Explain what is wrong with this electron dot diagram for the element nitrogen
How many molecules of N 2 are produced by reacting 0.0024 grams of NaN 3 according to the equation: 3 CuCl(aq) 3 NaN 3(aq) ---> Cu 3N(s) 3 NaCl(aq) 4 N 2(g)
Answer:
4 molecules
Explanation:
In the products side of the equation, you see 4N2, this means there are 4 molecules of N2 that are produced by the reaction.
Write the balanced chemical equation for the reaction
of solid carbon with oxygen gas to form carbon monoxide gas.
Answer:
2C +O2 - COExplanation:
mark me brainliest
The balanced chemical equation for the reaction of solid carbon with oxygen gas to form carbon monoxide gas is 2 C + O₂[tex]\rightarrow[/tex] 2 CO.
What is chemical equation?Chemical equation is a symbolic representation of a chemical reaction which is written in the form of symbols and chemical formulas.The reactants are present on the left hand side while the products are present on the right hand side.
A plus sign is present between reactants and products if they are more than one in any case and an arrow is present pointing towards the product side which indicates the direction of the reaction .There are coefficients present next to the chemical symbols and formulas .
The first chemical equation was put forth by Jean Beguin in 1615.By making use of chemical equations the direction of reaction ,state of reactants and products can be stated. In the chemical equations even the temperature to be maintained and catalyst can be mentioned.
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Question ( please help me )
1 . Which diagram shows pure substance that are elements
2. Which diagram shows pure substance are compounds
3. Which diagram shows a mixture of compounds
4. Which diagram shows a mixture of elements
5. Which diagram shows a mixture of an element and a compound
Answer:
1. F, H, E
2. A, D, I
3. G
4. E, B, H
5. C
Explanation: