Assuming a half life of 1599 years, how many years will be needed for the decay of 15/16 of given amount of radium-226​

Answers

Answer 1

Answer:

1

Explanation:


Related Questions

How do you calibrate an electronic analytical balance​

Answers

Explanation:

For the calibration process, use a weight that is 50% of the scale's capacity for accurate calibration. Weights less than 10% can result in inaccuracy. Make sure that the scale doesn't have any weights placed on it and nothing is rubbing against the scale or the platform.

What volume is occupied by 2.0 mol of gas at 3.0 atm
and 27 °C?

Answers

STP conditions imply a temperature of 273.15 K and a pressure of 100 kPa. When tose conditions are met, 1 mole of any ideal gas will have a volume of 22.7 L. So, if 1 mole occupies a volume of 22.7 L, 2 moles will occupy a volume twice as big. Likewise, 0.5 moles will occupy half the volume 1 mole occupies.

A binary covalent bond exists between

A.any element

B.2 nonmetals

C.1met and 1 nonmetal

D.2 metals

Answers

Answer:

B

Explanation:

Double Covalent bonds or as you say "binary" bonds consists of 2 non-metals only, nothing else.

Hope this helps!

1. Alexa and her family travelled 5 hours south east on 1-45 to crystal
beach this summer for vacation. If the trip was a total of 340 miles,
what was her average speed?
EQUATION
PLUG N NUMBERS
INTO THE EQUSTION
ENALANSWER WITH
UNTS

Answers

Answer:

Average speed  = 68 mph

Explanation:

Given that,

Total distance traveled by the family, d = 340 miles

The family traveled 5 hours southeast.

We need to find her average speed. The speed of an object is given by the total distance covered divided by time taken. So,

[tex]v=\dfrac{d}{t}[/tex]

Put all the values,

[tex]v=\dfrac{340}{5}\\\\v=68\ mph[/tex]

So, her average speed is equal to 68 mph.

Ammonia will decompose into nitrogen and hydrogen at high temperature. An industrial chemist studying this reaction fills a 5.0L flask with 4.5 atm of ammonia gas, and when the mixture has come to equilibrium measures the amount of nitrogen gas to be 1.1 atm. Calculate the pressure equilibrium constant for the decomposition of ammonia at the final temperature of the mixture. Round your answer to 2 significant digits.

Answers

Answer:

Kp = 7.4727

Explanation:

Let's write the balanced equilibrium reaction:

2NH₃ <-------> N₂ + 3H₂     Kp = ??

Now, if we want to calculate the Kp, we need to write an ICE chart with this reaction, which is the following:

         2NH₃ <-------> N₂ + 3H₂  

I.         4,5                 0        0

C.       -2x                +x     +3x

E.        4,5-2x            x       3x

According to this chart, the Kp expression should be:

Kp = (PH₂)³ * (PN₂) / (PNH₃)²   (1)

The value of x, we already know it because the problem states that the amount of nitrogen gas is 1.1 atm, so replacing this value into (1) we have:

Kp = (3*1.1)³ * (1.1) / (4.5 - (2 * 1.1))²

Kp = 39.5307 / 5.29

Kp = 7.4727

Hope this helps

suggest reasons why it is necessary to standardise HCl and NaOH solutions​

Answers

Answer:

look at explanation

Explanation:

the actual concentration of the NaOH solution has to be determined experimentally using a process called standardization. To standardize a base solution such as NaOH, an acid whose amount can be determined to a high degree of accuracy (called a primary standard) is needed.

Hope this helps!

How many mL of a 6 M NaOH stock solution is needed in order to prepare 500 mL of a 0.2 M NaOH solution?

Answers

Answer:

The right answer is "16.67 mL".

Explanation:

Given:

Molarity of NaOH,

[tex]M_1=6 \ M[/tex]

[tex]M_2=0.2 \ M[/tex]

Volume of NaOH,

[tex]V_1=V \ mL[/tex]

[tex]V_2=500 \ mL[/tex]

As we know, the equation,

⇒ [tex]M_1V_1=M_2V_2[/tex]

On putting the values, we get

⇒ [tex]6\times V=0.2\times 500[/tex]

⇒ [tex]6\times V=100[/tex]

⇒        [tex]V=\frac{100}{6}[/tex]

⇒            [tex]=16.67 \ mL[/tex]      

When 1 mol of a nonvolatile, nondissociating solute is dissolved in 3 mol of volatile solvent, the ratio of vapor pressure of the solution to that of the pure solvent (at the same temperature) is approximately:________

Answers

Answer:

[tex]\frac{P_{solution}}{P_{solvent}^{vap}} =0.75[/tex]

Explanation:

Hello there!

In this case, since the solvation of a nonvolatile-nondissociating solute in a volatile solvent is modelled via the Raoult's law:

[tex]P_{solution}=x_{solvent}P_{solvent}^{vap}[/tex]

Thus, we can calculate the ratio of the vapor pressure of the solution to that of the pure solvent, mole fraction, as shown below:

[tex]x_{solvent}=\frac{P_{solution}}{P_{solvent}^{vap}} =\frac{n_{solvent}}{n_{solute}+n_{solvent}}[/tex]

Thus, we plug in the moles of solvent and solute to obtain:

[tex]\frac{P_{solution}}{P_{solvent}^{vap}} =\frac{3}{3+1}\\\\ \frac{P_{solution}}{P_{solvent}^{vap}} =0.75[/tex]

Regards!

A solid sample is hit with a hammer and breaks into jagged, irregular shards. What type of solid was it? A) molecular solid b) network solid c) ionic solid d)metallic solid

Answers

I honestly don't know the answer

Transparency is a ____
of matter.

property
substance
type

Answers

Answer: -property

Explanation: Transparency is a property  of matter.

Answer: property i think

Explanation:

The titration of HCl with NaOH is an example of:
A. a weak acid-weak base titration,
B. a weak acid-strong base titration.
c. a strong acid-strong base titration.
D. a strong acid-weak base titration.

Answers

Answer:

I’m pretty sure it’s C

Explanation:

AP Ex

Which type of reaction is represented by this graph?
Potential energy
Reaction progress
A. Synthesis
B. Endothermic
C. Decomposition
D. Exothermic

Answers

Answer:

D. Exothermic .

Explanation:

Hello there!

In this case, since the potential energy versus reaction progress diagrams are related to the energetic profile of a chemical reaction, we can set the initial point at the beginning of the reaction as the energy of the reactants and the final point as the energy of the products.

Next, since the change in the enthalpy of a reaction is quantified by subtracting products minus reactants, we can see that the products have less energy than the reactants and therefore ΔH for this reaction is negative, which matches with the definition of D. Exothermic  reaction.

Regards!

Please help will give brainliest to right answer!!
You add 1.5 moles of HF to 6 liters of water. The concentration is at equilibrium when [H+] is at 0.10 M. What is the Ka of HF? HF -> H+ + F-.

A) 0.067
B) 0.10
C) 0.25
D) 1.5

Answers

Answer:

C

Explanation:

NP

A…………………………………………………..

Write the structure of all possible peptides containing these amino acids: Asp, Glu, Gln Use single letter abbreviations and capital letters only; i.e. GYR, not Gly-Tyr-Arg. If there are fewer than 6 peptides, leave an appropriate number of answer boxes empty. fill in the blank 1 , fill in the blank 2 , fill in the blank 3 , fill in the blank 4 , fill in the blank 5 , fill in the blank 6

Answers

Answer:

QED,  EDQ,  DQE,  EQD,  DEQ,  QDE

Explanation:

The structure of all possible peptides that contain the given amino acids are :

QED,  EDQ,  DQE,  EQD,  DEQ,  QDE

where : Asp is represented by the letter code D

             Glu is represented by the letter code E

             Gln is represented by the letter code Q

Note : when three amino acids combine they form what is known as tripeptide ( i.e. contains two peptide linkages ) while a peptide linkage is been formed by the combination of a carboxyl group of an amino acid and the amino group of different amino acid

1. Arrange the following groups in order of decreasing priority that would allow you to determine E/Z, or R/S. Provide a string of letters (e.g. abcd) as an answer with the highest priority listed first, lowest priority last:a) -CH3
b) -CH2OH
c) -CH2NH2
d) -CH2BR2. Arrange the following groups in order of decreasing priority that would allow you to determine E/Z, or R/S. Provide a string of letters (e.g. abcd) as an answer with the highest priority listed first, lowest priority last:a) -F
b) -CH2OH
c) -CHO
d) -CH3

Answers

Answer:

1. CH₂Br > CH₂OH > CH₂NH₂ > CH₃

2. -F > -CHO > - CH₂OH > CH₃

Explanation:

The arrangement of the above atom is due to their atomicity and electronegativity of the given compounds.

From (1) we will realize that Bromine (Br) possesses the greatest priority because its atomic number is the highest. This is followed by oxygen (O) in CH₂OH since atomic no 8 is higher than that of Nitrogen N(7). Lastly, CH₃ has the only hydrogen attached to it with the atomic no of (1)

In the second part of the question>

The electronegativity of an element increases across the period and down the group. Fluorine is highly electronegative and contains the highest atomic number of oxygen in -CHO. The oxygen (O) in -CHO has a double bond which gives an edge over the (O) in CH₂OH. Lastly, CH₃ contains a substituted hydrogen atom

PLEASE HURRY I WILL GIVE BRAINYEST
Where are the majority of temperate grasslands located?
A interiors of continents
B along the coastline
C in desert regions
D between mountain ranges

Answers

Answer:

D. Between mountain ranges

Explanation:

Usually in between mountains is where the most grass is.

Answer:

in the interior of continents

Explanation:

how much corn syrup should be added to water to make 200 mL of a 10% by volume solution​

Answers

....20 ml corn syrup

To make 200 mL of a 10% by volume solution, add 20 mL corn syrup to water.

What is volume solution?Volume percent of a solution is defined as the ratio of the volume of solute present in a solution to the volume of the solution as a whole. It means that the volume of a closed figure determines how much three-dimensional space it can occupy. In terms of numerical value, volume is the amount of three-dimensional space enclosed by a closed surface. For example, a substance's space can be solid, liquid, gas, or plasma, or any other space-occupying shape. The volume percentage of a solution can be calculated by dividing the volume of solute by the volume of solution and multiplying the result by 100. The basic formula for volume is length width height, whereas the basic formula for area of a rectangular shape is length width height. The calculation is unaffected by how you refer to the various dimensions: you can, for example, use 'depth' instead of 'height.'

To learn more about volume solution, refer to:

https://brainly.com/question/27030789

#SPJ2

2. According to decreasing ionization energy
Cr
со
Fe
V
Mn​

Answers

Answer: V, Mn, Cr, Fe, Co

Explanation: all elements belong to 4th period. Ionization energy increases from

Left to right

How many L of 3.0M solution
can be made with 78g of
NaCl?

Answers

Answer:

Need to find moles NaCl.

526 grams NaCl (1 mole NaCl/58.44 grams)

= 9.0 moles NaCl

----------------------------------------------------

now,

Molarity = moles of solute/Liters of solution

or, for our purposes

Liters of solution = moles of solute/Molarity

Liters of solution = 9.0 moles NaCl/3.0 M

= 3.0 liters in volume

What is all the colors in a rainbow​

Answers

Answer:

Red, orange, yellow, green, blue, indigo, violet.

Explanation:

Answer:

Red, orange, yellow, green, blue, purple, violet.

Explanation:

Se prepara una concentración molar 0.5M de hidróxido de sodio (NaCH) con la finalidad de determinar el grado de acidez de una bebida embotellada. Calcula la cantidad de gramos de hidróxido de sodio (NaCH) que se requiere para preparar 5 litros de dicha solución.​

Answers

Answer:

100 g

Explanation:

Primero hay que calcular el número requerido de moles de NaOH, usando la definición de molaridad:

Molaridad = moles / litros0.5 M = moles / 5 Lmoles = 2.5 moles

Ahora hay que convertir 2.5 moles de NaOH en gramos, usando su masa molecular:

2.5 mol * 40 g/mol = 100 g

Se requieren 100 gramos de NaOH.

PLEASEEE HELPPP WILL MARK BRAINLIEST FOR RIGHT ANSWER!!!
You have an unknown concentration of 0.035 L of HCl acid and added 0.033 L of 0.3 M NaOH before the equivalence point was reached. What is the concentration of the HCl?
HCl + NaOH -> H2O + NaCl

A) 0.28 M HCl
B) 0.11 M HCl
C) 0.035 M HCl
D) 3.14 M HCl

Answers

Answer:

A

Explanation:

Answer:

C

Explanation:

Pretty sure!

1. What would happen to an inflated balloon it were to be placed in a cold environment?
The balloon would inflate more
The balloon would pop
The balloon would float away
The balloon would deflate

Answers

Answer:

The balloon would deflate

Explanation:

Will mark brainliest

Calculate the specific heat of a substance given that 512 joules of heat is required to raise the temperature of 255.0 g of the substance by 15.0 ºC.

Answers

Answer:

[tex]c=0.133\ J/g^{\circ}C[/tex]

Explanation:

Given that,

Heat required, Q = 512 J

Mass of the substance, m = 255 g

The change in temperature, [tex]\Delta T=15^{\circ} C[/tex]

Let c be the specific heat of the substance. We know that the heat required to raise the temperature is given by :

[tex]Q=mc\Delta T[/tex]

Where

c is the specific heat of a substance

So,

[tex]c=\dfrac{Q}{m\Delta T}\\\\=\dfrac{512}{255\times 15}\\\\c=0.133\ J/g^{\circ}C[/tex]

So, the specific heat of the substance is equal to [tex]0.133\ J/g^{\circ}C[/tex].

What is the mass of 7.03 x 10- molecules of magnesium nitrate?

Answers

Answer:

173.5 g

Explanation:

This question seems incomplete, as the power by which 10 is increased is missing. I will answer this question assuming the given number of molecules is 7.03x10²³ molecules. A different number of molecules will give a different answer, but the procedure remains the same.

First we convert the given number of molecules into moles, using Avogadro's number:

7.03x10²³ molecules ÷ 6.023x10²³ molecules/mol = 1.17 mol

Then we convert magnesium nitrate moles into grams, using its molar mass:

1.17 mol * 148.3 g/mol = 173.5 g

g When a species can be represented by two or more resonance structures, the actual representation of bonding in the species is given by: A. the resonance structure with no multiple bonds B. the resonance hybrid of all structures C. the best resonance structure D. the resonance structure with no lone pairs on the central atom. E. the resonance structure with the most multiple bonds

Answers

Answer:

B. the resonance hybrid of all structures

Explanation:

The idea of resonance is used to explain bonding in compounds where a single structure does not fully account for all the bonding interactions in a molecule.

A number of equivalent structures are then used to show the nature of bonding in such a molecule. Such structures are called resonance structures or canonical structures. None of these structures individually offer a holistic explanation to the bonding interactions in the molecule under study.

However, a hybrid of all the canonical structures does explain the nature of bonding in the molecule.

Answer:

B. the resonance hybrid of all structures

Explanation:

When a species can be represented by two or more resonance structures, the actual representation of bonding in the species is given by: the resonance hybrid of all structures

Help Anyone! What would be the correct answer to this question?

Answers

I have no clue..........

Calculate the specific heat of a substance given that 49 joules of heat is required to raise the temperature of 25.0 g of the substance from 92.6 ºC to 99.4 ºC.

Answers

Answer:

0.29 J/g.°C

Explanation:

Step 1: Given data

Added heat (Q): 49 JMass of the substance (m): 25.0 gInitial temperature: 92.6 °CFinal temperature: 99.4 °C

Step 2: Calculate the temperature change (ΔT)

ΔT = 99.4 °C - 92.6 °C = 6.8 °C

Step 3: Calculate the specific heat of the substance (c)

We will use the following expression.

Q = c × m × ΔT

c = Q / m × ΔT

c = 49 J / 25.0 g × 6.8 °C = 0.29 J/g.°C

A newborn blue whale measures 6.0 to 7.9 m long and weighs up to 3003 kg. The blue whale produces the loudest sound by any living animal, 188 dB and can be detected as far as 850 000 m away. What is the total number of significant figures in all these trivia?

Answers

H
Ztdtdyfugughfhfhdtxycycyfugufufuvuguguv

What is the hydrogen ion concentration of a solution with pH=7.75 ?

Answers

Answer:

[tex][H^+]=1.78x10^{-8}M[/tex]

Explanation:

Hello there!

In this case, according to the given information about the pH, it is firstly necessary for us to remember that the pH is defined as the potential of the hydrogen ions in the solution and the concentration of those ions represents how many of them are present in the solution; in such a way, it is possible for us use:

[tex]pH=-log([H^+])[/tex]

Whereas the concentration of hydrogen ions can be calculated as follows:

[tex][H^+]=10^{-pH}[/tex]

So we plug in the given pH to obtain:

[tex][H^+]=10^{-7.75}=1.78x10^{-8}M[/tex]

Regards!

Other Questions
Hey guys, summers almost here!! which means things that you can plan for the summer, what are your plans for the sumer?? 4 + (m -n )^4 when m =7 and n = 5 whats the value ? Rommer Company purchases Daley Inc. for $4,700,000 cash on January 1, 2020. The book value of Daley Company's net assets, as reflected on its December 31, 2019 statement of financial position is $4,000,000. An analysis by Rommer on December 31, 2019 indicates that the fair value of Daley's tangible assets exceeded the book value by $525,000, and the fair value of identifiable intangible assets exceeded book value by $150,000. How much goodwill should be recognized by Rommer Company when recording the purchase of Daley Inc. 9The volume of a cylinder is 121 cubic inches and its height is 4 inches.a)What is the radius of the cylinder?b) What is the surface area of the cylinder? Give your answer in terms of t. The annual demand for a product is 14,400 units. The weekly demand is 277 units with a standard deviation of 80 units. The cost to place an order is $28.00, and the time from ordering to receipt is eight weeks. The annual inventory carrying cost is $0.10 per unit. a. Find the reorder point necessary to provide a 95 percent service probability. (Use Excel's NORM.S.INV() function to find the z value. Round z value to 2 decimal places.) What is the theoretical probability of landing on NOT green?A. P(green)= 4/5B. P(green)= 3/4 C. P(green)= 1/5D. P(green)= 5/8 explain the term information security? what is a material used to reduce or prevent the transfer of electricity, heat, or sound ? Enter an algebraic expression to model the given context. Give your answer in simplest form.The principal amount P originally deposited in a bank account plus 0.8% interestThe algebraic expression is You can buy 15 stickers for $10 how much would 12 stickers cost PLS HELP I GIVE CROWN THINGY Lisa, an experienced shipping clerk, can fill a certain order in 13 hours. Felipe, anew clerk, needs 15 hours to do the same job. Working together, how long will ittake them to fill the order? It is assumed that the mean weight of a Labrador retriever is 70 pounds. A breeder claims that the average weight of an adult male Labrador retriever is not equal to 70 pounds. A random sample of 45 male Labradors weigh an average of 72.5 pounds with a standard deviation of 16.1 pounds. Test the breeder's claim at Pat made a total of 48 pottery plates and cups, how many plates did she make? Which set of transition words, in order, best clarifies the order of events in thepassage?Anna Mae walked past the barn toward the house. 1, she heard astrange noise coming from inside. It was Blush, her favorite cow, andshe was about to have a calfi Anna Mae called for Pa and Uncle Bart tocome quickly. L), they were all huddled around Blush's stall. Themen seemed to know just what to do, and Anna Mae watched silentlyas they went to work. ), the other cows stamped nervously at allthe commotion,A. Consequently, Long ago, After thatB. All at once, Suddenly, SoonO C. Suddenly, Soon, MeanwhileO D. Afterward, Meanwhile, Nevertheless how does mitosis relate to the immune system The British government raised taxes because can someone help with this? immediately! what was the significance of the emancipation proclamation? what effect did it have on the north and on the south At 3:00 pm the temperature in Pittsburgh was 93 degrees Fahrenheit decreased at a rate of 2 degrees Fahrenheit every 30 minutes. What was the temperature at 7:30 pm?