The radiostope radon 222 has a half life of 3.8 days. How much of a 73.9-g sample or radon 222 wouppd be left after 23 days ?? pls show an equation​

Answers

Answer 1

Answer:

Is there a picture for it

Explanation:

because it would be a hard


Related Questions

The metric system is also known as the

Answers

Answer:

THE answer is all of above

Explanation:

The metric system, also known as the Système international d'unités (SI), was developed in the late 1700s to standardize units of measurement in Europe. The metric system is the primary system of measurement used through much of the world and in science.

What is the delta H when 72.0 grams H2O condenses at 100.00C?

Here are some constants that you MAY need.

specific heats heat of fusion heat of vaporization

H2O(s) = 2.1 J/g0C 6.01 kJ/mole 40.7 kJ/mole

H2O(L) = 4.18 J/g0C

H2O(g) = 1.7 J/g0C



2930 kJ


163 kJ


-163 kJ


-2930 kJ

Answers

Answer: The value of [tex]\Delta H[/tex] is -163 kJZ

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)

We are given:

Given mass of water = 72.0 g

Molar mass of water = 18 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of water}=\frac{72.0g}{18g/mol}\\\\\text{Moles of water}=4mol[/tex]

Calculating the heat released for the condensation process:

[tex]\Delta H=n\times \Delta H_{(vap)}[/tex] ......(2)

where,

[tex]\Delta H[/tex] = amount of heat released

n = number of moles of water = 4 moles

[tex]\Delta H_{(vap)}[/tex] = specific heat of vaporization = -40.7 kJ/mol

Negative sign represents the amount of heat released.

Putting values in equation 2:

[tex]\Delta H=4mol\times (-40.7kJ/mol)=-163kJ[/tex]

Hence, the value of [tex]\Delta H[/tex] is -163 kJ

Which of the following could possibly be true about a strong acid? (Check all that apply:).
It will completely dissociate (break apart) when dissolved in water.
It could have a pH of 6
It could have a pH of 13
Only a few of the acid molecules will dissociate (break apart).
It could have a pH of 2.
It could have a pH of 9

Answers

Answer:

it could have a pH of 2 it will completely dissociate when dissolved in water

How are liquid water, ice, water different from each other?

Answers

Answer: In liquid water, water molecules are moving faster. They are still close together, but they are no longer stuck in a rigid pattern as they are in ice. Water molecules in liquid water are constantly sliding past and bumping into each other; they keep moving from one place to another.

Answer:

they are different forms

Explanation:

ice is solid

and water is liquid

they also have different densities

Which of the following best describes an electron transition?

A. An electron gains or loses energy and moves between continuous
energy levels.
B. An electron gains or loses charge and changes into a proton or a
neutron.
C. An electron gains or loses energy and moves between quantized
energy levels.
D. An atom gains or loses an electron and becomes an ion.

Answers

Answer:

A. An electron gains or loses energy and moves between continuous

energy levels.

calculate the molecular weight of CaCO3.​

Answers

Answer:

Explanation:

CaCO3 = 1*Ca + 1*C + 3*O

              =1*40 + 1*12 + 3*16

               =40 + 12 + 48

               =100 amu

       

Which two laws were discovered by Antoine Lavoisier and Joseph Proust?

Answers

Dalton’s law of multiple proportion and law of conservation of mass

WHAT HAPPENS WHEN ELECTRIC CURRENT PASSES THROUGH ACIDIFIED WATER.

Answers

Answer:

When an electric current is passed through acidified water, it decomposes to give hydrogen and oxygen gas. The hydrogen gas is obtained at the cathode and the oxygen gas is obtained at the anode

Explain why solids and liquids are difficult to compress
whereas gases can easily be compressed.

Answers

Answer:

Because they take up a certain amount of volume because there is no space in-between the particles, a gases can be compressed because there is alot of space in-between each particle

Explanation:

Chemistry 1 question please help!! 10 points

Answers

Answer:

3

Explanation:

its the 3 one it is

A + 2 B + 4 C → products is known to be second order in A, first order in B and independent of the concentration of C. What is the value of the rate constant for this reaction if its rate is 0.783 M · s−1 when [A] = 5.00 M, [B] = 7.00 M, and [C] = 3.00 M? −2 −1 Answerinunitsof M ·s .

Answers

Answer:

4.47 × 10⁻³ M⁻² s⁻¹

Explanation:

Let's consider the following generic equation.

A + 2 B + 4 C → products

This reaction is known to be second order in A, first order in B and independent of the concentration of C (zero order in C). The rate law is:

rate = k × [A]² × [B] × [C]⁰

rate = k × [A]² × [B]

where k is the rate constant

When the rate is 0.783 M/s, [A] = 5.00 M, [B] = 7.00 M, and [C] = 3.00 M, the rate constant is:

k = rate / [A]² × [B]

k = 0.783 M/s / (5.00)² × (7.00) = 4.47 × 10⁻³ M⁻² s⁻¹

What is the pH of a solution?
O A. A measure of the strength of the acid
B. A measure of the buffering ability of the solution
O c. A measure of the hydrogen gas concentration
O D. A measure of the acidity of the solution

Answers

Answer:

D. A measure of the acidity of the solution

Explanation:

pH is a measure of how acidic or basic a solution is, and is measured on a scale from 0-14, where 7 is neutral, anything less than 7 is acidic, and anything more than 7 is basic.

Given the structural formula: This compound is classified as an

Answers

Answer:

A.) aldehyde is the answer

From the given structural formula, the compound is ethanamide and thus, belongs to the group of amides. Thus, the correct option is B.

Amide is a functional group of organic compounds having an acyl group (R-C=O) linked to amine group (-NR¹R² where R¹ and R² are hydrogen atoms or alkyl groups). The amide functional group is given as -CON= (not double bond with N, but two distinct single bonds).

Amides can be classified into the following types depending on the moiety attached to nitrogen other than the carbonyl carbon:

1. Primary amides - amide in which the nitrogen atoms is attached to two hydrogen atoms

2. Secondary amides - in which the nitrogen atom is attached to one hydrogen and one alkyl group.

3. Tertiary amides - in which the nitrogen atom is attached to two alkyl groups.

Learn more about amides in:

https://brainly.com/question/29595493

#SPJ2

an engineer chooses to use bamboo as a building material because it grows quickly and needs little space to grow. This is an example of?

Answers

Mark Brainliest please

Answer: This is an example of Green Design

Green design can be described as a method in which any building project is made by minimizing the harmful effects of construction on humans and environment. Green design is a sustainable design which is better for the economy too. In a green design, eco- friendly materials are used for construction works.
In the scenario discussed in the question, an engineer is using bamboo as a building material due to its eco- friendly features. Hence, it is an example of green design.

Answer:

A) This is an example of Green Design

Explanation:

Which of the following statements is correct about electrical insulators?
A. They do not contain any atoms.
B. Their protons are not allowed to move about freely.
C. The electrons are not able to move about freely.
D. They are good at conducting heat only.

Answers

Answer:

the answer is C in my opinion.. hope this might be helpful

Which sequence of steps describes the life cycle of a lake?
A. Runoff fills a depression - sediments build up - water becomes
increasingly shallow
B. Runoff fills a depression - sediments are eroded - water becomes deeper
C. Runoff fills a depression - sediments build up
- water rises continuously
D. Runoff fills a depression - sediments are eroded - water spreads over a wider area

Answers

Answer:

The actual sequence of steps which describe the life cycle of a lake is given below:

C. Runoff fills a depression - sediments build up

- water rises continuously

Explanation:

This is because, the water which builds up as a result of the runoff water accumulating on the depression helps towards building up. When it must have accumulated greatly, it ends up forming a lake.

Which defines the word planet?


A. A large body that revolves around the Moon.
B. A large body suitable for life.
C. A large body that contains water and land.
D. A large body that revolves around the Sun.

Answers

Answer:

I think it's D cause one of the requirements for a planet is that it has to revolve around a star

if five elements have atomic numbers 2,3,6,9 which two numbers are the most reactive??​

Answers

Explanation:

[tex]element \: with \: 2 \: atomic \: number \\ \\ is \: stable \: because \: it \: has \: already \: \\ \\ completed \: its \: orbit \: \\ \\ but \: atomic \: number \: with \: 3 \: and \: 9 \\ \\ will \: have \: to \: become \: stable \: \\ \\ after \: giving \: one \: electron \\ \\ so \: \: element \: with \: 3 \: and \: 9 \: atomic \: number \\ \\ is \: most \: reactive[/tex]

What happens when an unstable nucleus undergoes radioactive decay?
A. Electrons change energy levels to balance the nucleus.
B. Energy is absorbed by the nucleus to make it more stable.
O C. Particles or electromagnetic radiation are emitted.
D. The nucleus increases in mass through radioactive decay.

Answers

i believe the answer is C. an unstable nucleus emits radiation and is transformed into the nucleus of one or more elements. i hope this helps!

Use mathematics to prove that the 5.50 grams of salicylic acid (C7H6O3) used in this experiment is equal to 0.04 mol.

Answers

Answer:

Please find the answer to the question below

Explanation:

In chemistry, the following mathematical formula is used to calculate the number of moles contained by a substance:

mole = mass of substance (g)/molar mass of substance (g/mol)

Molar mass of salicylic acid (C7H6O3) = 12(7) + 1(6) + 16(3)

= 84 + 6 + 48

= 138g/mol

Mass = 5.50grams

mole = 5.5/138

mole = 0.039

Approximately, the number of moles of 5.5grams of salicylic acid is 0.04moles. This is in accordance with the mole value (0.04) given in this question.

Por qué razón se fomenta la inmigración Europea?​

Answers

Hola aquí va la respuesta!

Se fomentó la inmigración europea porque la economía no era buena y vinieron a Paraguay para mejorar su situación.

Hola aquí va la respuesta!

Se fomentó la inmigración europea porque la economía no era buena y vinieron a Paraguay para mejorar su situación.

Which question would most likely be studied by a biologist?
A.
How can a drug that treats cancer be synthesized?
B.
How can cancer-causing substances be regulated?
C.
How much ultraviolet radiation passes through the atmosphere?
D.
What causes cancer cells to grow uncontrollably?

Answers

Answer:

The correct answer would be - D. What causes cancer cells to grow uncontrollably?

Explanation:

A Biologist is a person that studies living organisms and the study of living organisms and their process called biology. Biology is a very vast field that involves many branches such as zoology, botany, biochemistry, immunology, biophysics, anatomy, ecology and many more.

So, given all are can be an example of the study biology wanted to do, however, the question most likely studied by a biologist would be What causes cancer cells to grow uncontrollably as it deals with an organism and their biological process.

An example of a product made from a synthetic material is
Question 5 options:

A)

a PET plastic water bottle.

B)

knitted wool socks.

C)

a cotton t-shirt.

D)

a pine 2×4 board.

Answers

Hi there! A simple answer and explanation is below :)

Answer:

A) PET plastic water bottle

Explanation:

Plastic goes through a manufacturing process before being used to make bottles for liquids like milk, soda, motor oil, and shampoo, as well as dry items like pharmaceuticals and nutritional supplements. Plastic is made up of a variety of organic polymers, including polyethylene and ethylene, in its unprocessed condition. In a soft state, plastic can be molded into the desired shape and then cast into a solid stat

What does a vacuole mean

Answers


a small cavity or space in tissue, especially in nervous tissue as the result of disease.

Answer:

a space or vesicle within the cytoplasm of a cell, enclosed by a membrane and typically containing fluid.

or

a small cavity or space in tissue, especially in nervous tissue as the result of disease.

4. What is a renewable resource? List some examples.

Answers

Answer:

Renewable resources include biomass energy (such as ethanol), hydropower, geothermal power, wind energy, and solar energy. Biomass refers to organic material from plants or animals. This includes wood, sewage, and ethanol (which comes from corn or other plants).

five examples of renewable resources

Solar energy.

Wind energy.

Geothermal energy.

Hydropower.

Bioenergy.

I hope it help you

Answer:

The most popular renewable energy sources

currently are

Solar energy

Wind energy

Hydro energy

Tidal energy

Geothermal energy

Biomass energy

A. 2 pts: In terms of conservation of mass, what were the results of each experiment (which one conserved mass and which one did not)?
B. 4 pts: PROVIDE a SPECIFIC explanation for "why" the results in both videos were different.
. 2 pts: Discuss differences in the experimental steps between the two videos (for example what was done in video one that was not done in
video two, why would this make a difference in conserving mass?)
• 2 pts: Look at both chemical equations (below for convenience), what difference in the type of products would have contributed to the
differences in why one conserved mass and one did not?
REACTION 1: Pb(NO3)2 (aq) + 2K1 (aq) --> 2KNO3 (aq) +Pölz (s)
• REACTION 2: NaHCO3(s) + CH3COOH(aq) → CO2(g) + H2Om + CH3COONa(aq)

Answers

Answer:

dftdffdgxrdfdrdxxxxdddddddddddddeeertdffddy

Briefly explain why adding insulation to an attic helps reduce heating costs.

Answers

Answer:

Insulation reduces the exchange of heat through a surface such as a wall, attic, duct or roof. In a well-insulated home, less warm air escapes from the house during the winter, and less cool air escapes during the summer, reducing the amount of energy needed for heating and cooling

Consider the following intermediate chemical equations.
CH2(g) →C(s) + 2H2(g)
CC1.(g) → C(s) +2012(g)
H2(g) +C12(g) → 2HCl(9)
ΔH, = 74.6 kJ
ΔH2 = 95.7 kJ
ΔΗ =
ΔHg =-92.3 kJ
What is the enthalpy of the overall chemical reaction CH (g) +4012(g) → CCl4(h)+ 4HCl(g)?

Answers

Answer: The enthalpy of the overall chemical equation is -205.7 kJ

Explanation:

Hess's law is defined as the law which states that the total amount of heat absorbed or released for a given chemical reaction will remain the same whether the process occurs in one step or several steps.

In this law, a chemical equation is treated as an ordinary algebraic expression that can be added or subtracted to yield the required overall equation.  

The enthalpy change or heat of the overall reaction is the summation of the enthalpies or heats of the intermediate reactions involved in the process.

The given overall chemical equation follows:

[tex]CH_4(g)+4Cl_2(g)\rightarrow CCl_4(g)+4HCl(g);\Delta H^o_{rxn}[/tex]

The intermediate equations for the above reaction are:

(1)  [tex]CH_4(g)\rightarrow C(s)+2H_2(g);\Delta H_1=74.6 kJ[/tex]

(2)  [tex]CCl_4(g)\rightarrow C(s)+2Cl_2(g);\Delta H_2=95.7kJ[/tex]

(3)  [tex]H_2(g)+Cl_2(g)\rightarrow 2HCl(g);\Delta H_3=-92.3kJ[/tex]

According to Hess law, the enthalpy of the reaction becomes:

[tex]\Delta H^o_{rxn}=[1\times (\Delta H_1)] + [1\times (-\Delta H_2)] + [2\times (\Delta H_3)][/tex]

Putting values in above expression, we get:

[tex]\Delta H^o_{rxn}=[1\times (74.6)] + [1\times (-95.7)] + [2\times (-92.3)]\\\\\Delta H^o_{rxn}=-205.7kJ[/tex]

Hence, the enthalpy of the overall chemical equation is -205.7 kJ

Joelle is a manager at a construction company, and she is interested in the chemistry behind the materials they use. She has begun studying the materials used to fill walls. She knows that to keep the temperature inside a room steady the material must be a thermal insulator, and she predicts that materials should not be acidic or else they would dissolve too easily in water.

Which of these is a molecular ingredient that could be used in a wall-filling material ?

C27H36N2O10
Na6Ba6
NeNa
HCl

Answers

Answer:

a

Explanation:

A molecular ingredient that could be used in a wall-filling material is C₂₇H₃₆N₂O₁₀, is not a good thermal insulator, hence option A is correct.

The big molecule C₂₇H₃₆N₂O₁₀ is a poor thermal insulator. Since NeNa is a relatively reactive chemical, it would probably dissolve in water far too quickly. The acidic molecule HCl would dissolve far too quickly in water.

Not a good thermal insulator is C₂₇H₃₆N₂O₁₀. It is a big molecule composed of a lot of hydrogen atoms. Since hydrogen atoms are excellent heat conductors, they would be ineffective in stopping heat from passing through a material used to fill a wall.

Thus, the option (A) C₂₇H₃₆N₂O₁₀ is correct.

Learn more about thermal insulator, here:

https://brainly.com/question/23134662

#SPJ6

WHAT IS EXOTHERMIC EXPLAIN

please ।
।।।​

Answers

Answer:

Exothermic reactions are reactions or processes that release energy, usually in the form of heat or light. In an exothermic reaction, energy is released because the total energy of the products is less than the total energy of the reactants.

Explanation:

I hope this helps u have a nice day ☘

Answer:

An EXOTHERMIC reaction is when energy is released.

Other Questions
Discuss the any two applications of Beers law with suitable justification. 21 POINTS!! Thank you so much!! Theres also things on my page worth lots points points as well! So if you could help with those that would be awesome!! I got it partially right I think but I need help ! 1. Of the three angles in a right-angled triangle, one angle has a measureof 60 degrees. What is the measure of the third angle, Angle X? *al 60 In a game of chance,players spin a pointer on a spinner with eight equal-sized sections. Answer to the question Select the correct answer.What are the directions of an object's velocity and acceleration vectors when the object moves in a circular path with a constant speed?OA. The question is meanimgless, since the acceleration is zero..The vectors point in opposite directions.Oc.Both vectors point in the same direction.ODThe vectors are perpendicular, A person who forwards on a sexual picture of another can get in as much trouble as a person sending a picture of themselves (sexting). True False Please help mew ith this questionsasd What was one key WEAKNESS of the Articles of Confederation?A.it was not ratified by every stateB.it was too structured for the states to followC.it gave too much power to the federal governmentD.it gave too much power to the states please help me i have 5 minutes left: )! ill give Brainliest thanks The Union raised money for the war by taxing persons based on how much they made which was called _________________________. Rationalize 1/18Will Mark as Brainliest for the best 50 points easy read the following prompt.Think of something you would like to change in your neighborhood. Imagine you have the opportunity to make an appeal to the local leaders who, if convinced, have the power make the change you desire.Construct an outline that includes a claim, makes an appeal based on logos, and ends with a call to action.just wanna see people have an opinion cause some adults may forget that Answer please of that Please help!!!!! Will give brainlistYou call your best friend to invite him or her to a concert. Nobody answers the phone so you decide to leave a message. Record the message that you would leave for your friend. Your message should be at least 5 complete sentences in French. La camisa que lleva Mara es _____.1. blanca2. blancas3. blanco ou se trouve la course interne Which of the following instruments are traded in the capital markets? Check all that apply. Treasury bills Certificates of deposit Common stocks Commercial paper Preferred stocks in The Veldt, why does the story end with Peter and Wendy having a picnic behaving politely toward David McClean?