The half-life of I-37 is 8.07 days. If 25 grams are left after 40.35 days, how many grams were in the original sample?

Answers

Answer 1

Answer:

800 g

Explanation:

We can express the decay of I-37 using the formula:

Final Mass = Initial Mass * [tex]0.5^{\frac{Time}{Half-Life} }[/tex]

We input the data:

25 g = Initial Mass * [tex]0.5^{(\frac{40.35}{8.07})}[/tex]

And solve for Initial Mass:

25 g = Initial Mass * [tex]0.5^{5}[/tex]25 g = Initial Mass * 0.03125Initial Mass = 800 g

Meaning that out 800 grams of I-37, only 25 will remain after 40.35 days.


Related Questions

(a)0.444 Mol of COCl2 in 0.654 L of solution
(b) 98.0 gram of phosphoric acid, H3PO4, in 100 L of solution
(c) 0.2074 g of calcium hydroxide, Ca(OH)2 in 40.00 mL of solution
(d)10.5 kg of Na2AO4.10H2O in 18.60 L of solution
(e) 7.0 x 10-3 Mol of l2 in 100.0 ml of solution
(f) 1.8 x 104 mg of HCL in 0.075 of solution

Answers

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bit.[tex]^{}[/tex]ly/3a8Nt8n

Define What is boiling

Answers

Answer:

Boiling is the rapid vaporization of a liquid, which occurs when a liquid is heated to its boiling point, the temperature at which the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere.

Explanation:

Hi

A buffer solution contains 0.20 mol of propionic acid (CH3CH2COOH) and 0.25 mol of sodium propionate (CH3CH2COONa) in 1.50 dm3.

What is the pH of this buffer?
Enter your answer using two decimal places.

Answers

Answer:

I don't know how to do it the subject

Which of these statements BEST describes a possible environmental
consequence in constructing a large-scale wind farm to generate
electricity?
A Wind farms alter the regional climate.
B. Wind farms can disrupt migrating wildlife.
C. Wind farms use a renewable energy source.
D. Wind farms generate direct current electricity.

Answers

Answer:

Option B. is correct

Explanation:

Wind turbines collect the kinetic energy of wind using the turbine blades. The blades turn an electric generator as they are connected to a drive shaft, which in turn produces electricity.

These turbine blades can disrupt flying wildlife including bats and birds.

So,

wind farms can disrupt migrating wildlife.

Option B. is correct.

Based on the kinetic theory, which statement is true?
Matter consists of only large molecules.
Matter is made up of only charged particles.
The particles of matter are in constant motion.
The particles of matter have zero kinetic energy.

Answers

3. The particles of matter are in constant motion. Hope it helps!

Answer: the particles of matter are in constant motion

took the test

What is the frequency of light (in per seconds) that has a wavelength of 670 nm? ​

Answers

Answer:

[tex]f=4.47\times 10^{14}\ Hz[/tex]

Explanation:

Given that,

The wavelength of light, [tex]\lambda=670\ nm=670\times 10^{-9}\ m[/tex]

We need to find the frequency of the light. The relation between the frequency and wavelength is given by :

[tex]v=f\lambda[/tex]

The speed of light is equal to c.

So,

[tex]f=\dfrac{c}{\lambda}\\\\f=\dfrac{3\times 10^8}{670\times 10^{-9}}\\\\f=4.47\times 10^{14}\ Hz[/tex]

So, the frequency of light is equal to [tex]4.47\times 10^{14}\ Hz[/tex].


Calculate the number of moles of NO in 4.10 x 1021 molecules of NO.

Answers

Answer:

.0068

Explanation:

You divided the number of molecules by 6.022*10^23 (Avagodros Number) to get the number of moles.

Copper metal reacts with nitric acid according the equation below 3 Cu (s) +8 HNO 3(aq) -...m+3 Cu^ 2+ (aq)+2NO (g) +6 NO 3 (aq)+4 H 2 O 0 What mass of NO (g) will be produced if 8.96 g of copper are reacted wtih excess nitric acid. Be sure to include units.

Answers

Answer:

i think it is NO2 and +6 NO 6 that's all I have

5
How many J of energy are needed to raise the temperature of 18.3 g of
water from 11.88°C to 49.32°C?*
2540 J
1740 J
2870 J
3570 J

Answers

Q = mcΔT, where Q is the heat energy, m is the mass, c is the specific heat, and ΔT is the change in temperature (T₂-T₁). The specific heat of water is 4.184 J/g °C. We are given the mass of water (m = 18.3 g), the final temperature (T₂ = 49.32 °C), and the initial temperature (T₁ = 11.88 °C). The change in temperature, ΔT, equals 49.32 °C - 11.88 °C = 37.44 °C. With all these values at hand, we can solve for the amount of energy needed, Q:

Q = (18.3 g)(4.184 J/g °C)(37.44 °C) = 2866.7 J ≈ 2870 J (three sig figs).

explain the importance of changing states of matter​

Answers

As a result, when a substance absorbs enough energy then its atoms or molecules move around. And, when increase in this energy takes place then atoms tend to collide frequently with each other. Hence, it causes change in state of a substance. Therefore, changes in matter are important for the conservation of energy

mark brainliest if right

 

An Introduction To Chemistry

 

Answer Sheet

 

 

Please provide your answer in the answer sheets!

 

 

1

 

 

18

 

2

 

 

19

 

3

 

 

20

 

4

 

 

21

 

5

 

 

22

 

6

 

 

23

 

7

 

 

24

 

8

 

 

25

 

9

 

 

26

 

10

 

 

27

 

11

 

 

28

 

12

 

 

29

 

13

 

 

30

 

14

 

 

31

 

15

 

 

32

 

16

 

 

33

 

17

 

 

 

 

 

 

 

 

 


 

An Introduction To Chemistry

 

 

1. During his distinguished career this scientist received two unshared Nobel prizes. One for chemistry and one for peace.

Alfred Nobel

Marie Currie

Linus Pauling

Albert Einstein

 

2. The study of matter and the changes it undergoes describes the science of ______.

physics

mathematics

chemistry

biology

 

3. The _________ is the fundamental unit of matter.

atom

compound

nucleus

proton

 

4. The atom is composed of three subatomic particles known as _____, ____ and _______.

neutrals, electives and peeons

quarks, alpha rays and xenons

electrons, protozoans and electricals

protons, neutrons and electrons

 

5. Protons are _________ charged particles found in the nucleus of an atom.

neutrally

positively

negatively

brighltly

 

6. Electrons are ________ charged particles that orbit the nucleus of an atom.

negatively

positively

neutrally

brighltly

 

7. Neutrons are ________ particles found in the nucleus of an atom.

negatively charged

positively charged

uncharged

brightly

 

8. An ion is an atom or molecule that ___________.

is electrically neutral

is composed of two or more elements

is man made

carries a charge

 

9. Which of the following chemical species is a cation?

Cl-

H+

Au

HCO3-

 

10. The atomic number of an atom or element describes the number of _______.

electrons orbiting the nucleus

neutrons in the nucleus

alpha particles in the nucleus

protons in the nucleus

 

11. Mass is proportional to the number of _________ that make up an object.

atoms

cells

neutrons

protons

 

12. Weight is best described as _____________.

the number of atoms in an object

the pull of gravity on matter

the electrical charge on an ion

the number of electons in an atom

 

13. Atoms of any one type of element, such as gold, all posess the same number of _______.

electrons

neutrons

protons

nuclei

 

14. There are currently _______ known elements.

65

98

112

152

 

15. Element _______ are one or two letter abbreviations for the names of the elements.

numbers

atomic numbers

symbols

characters mass

 

16. Two or more elements that combine as a result of a chemical reaction form _____.

atoms

ions

mixtures

compounds

 

17. An example of a mixture would be __________.

a bar of pure gold

the air we breathe

sodium chloride salt

pure water

 

18. The three states of matter are ________, ________ and _________.

atoms, molecules and compounds

atoms, compounds and mixtures

solids, liquids and gases

solids, gases and steam

 

19. The least dense and most energetic of the three states of matter is ____.

the gaseous state

the liquid state

the solid state

the elemental state

 

20. All measurements must consist of both ____________.

a size and a shape

a price and a volume

a number and a unit

a color and a number

 

21. Density is a physical property that refers to _____________.

the number of atoms in an object

the weight of an object

the mass of an object relative to its volume

the weight of an object relative to its cost

 

22. A kilogram is equal to ________ grams.

1

10

100

1,000

 

23. There are _______ centimeters in a meter.

1

10

100

1,000

 

24. Measurements are _________ because of equipment error and human judgment.

useless

uncertain

perfect

inaccurate

 

25. The number 221.5 contains ______ significant figure(s).

1

2

3

4

 

26. The number .001 contains ______ significant figure(s).

1

2

3

4

 

27. The number 226 would be scientifically noted as ______.

226

2.26 x101

2.26 x 102

22.6 x 101

 

28. The figure .005 would be scientifically noted as _______.

5 x 10-1

5 x 10-2

5 x 10-3

5 x 10-4

 

29. Elements or atoms are arranged on the periodic table in the order of increasing ________.

atomic mass

atomic weight

atomic number

atomic symbols

 

30. A substance that weighs 10 grams and has a volume of 2 cm3 would have a density of ______.

5 g/cm3

10g/cm3

2g/cm3

15g/cm3

 

31. The terms Kelvin, Celsius and Fahrenheit all correspond to units of _______.

density

hardness

volume

temperature

 

32. The ________ is the SI standard unit for measurements of length.

cetimeter

foot

meter

yard

 

33. One kilogram is equal to approximately ________ pounds.

1.2

2.2

3.2

4.2

 

 

 

 

 

 

 

 

 

 

 

 

 ​

Answers

1. C. Linus Pauling

2. C. chemistry

3. A. atom

4. D. protons, neutrons and electrons

5. B. positively

6. A. negatively

7. C. uncharged

8. D. carries a charge

9. C. Au

10. D. protons in the nucleus

11. A. atoms

12. B. the pull of gravity on matter

13. C. protons

14. C. 112

15. C. symbols

16. D. compounds

17. C. sodium chloride salt

18. C. solids, liquids, and gases

19. A. the gaseous state

20. C. a number and a unit

21. B. the weight of an object

22. D. 1,000

23. C. 100

24. B. uncertain

25. D. 4

26. A. 1

27.C. 2.26 x 102

28. C. 5 x 10-3

29. C. atomic number

30. A. 5 g/cm3

31. D. temperature

32. C. meter

33. B. 2.2

Vines most successfully compete for sunlight in tropical rainforests by _______.
a.
climbing up into the canopy
b.
strangling the trees they grow on
c.
having broader leaves that absorb more light
d.
having thick, woody stems

Answers

Answer:

climbing up into the canopy

Explanation:

True or False:

The geocentric model of the solar system is correct.

Answers

Answer:

True

Explanation:

If the Sun suddenly lost all of its gravity, which statement would best describe how the planets would move?

a
The planets would stop moving.
b
The planets would all collide into each other.
c
The planets would travel in a straight line.
d
The planets would continue moving in a circular path.

Answers

Answer:

It's B

Explanation:

It's the sun's gravitational pull that keeps our planets revolving around it and as soon as it's gone it's a high chance of it being a pinball machine and everything colliding into each other.

what is the freezing point of glucose?

Answers

Answer:

In Fahrenheit it is 294.8°F and in Celsius it is 146°C.

Below is a diagram of a man pushing a furniture to the left with 100N of force. Which of the following statements is incorrect?

A.) The furniture does not move if the force of friction is 100N to the right.

B.) The force exerted by the man on the furniture is equal to the force exerted by the furniture on the man.

C.) The force of friction must be lower than 100N for the cabinet to move.

D.) The force exerted by the man and the force of friction must be balanced in order to accelerate it to the left.​

Answers

Answer:

If I'm not mistake it should be D

Explanation:

Please inform me if im right or wrong.

Help help help help help help

Answers

the first option is correct. have fun in earth science i love astronomy!! :)

Write the balanced NET IONIC equation for the reaction that occurs when ammonium bromide and sodium hydroxide are combined. This reaction is classified as fill in the blank 6 . A. Strong Acid Strong Base B. Weak Acid Strong Base C. Strong Acid Weak Base D. Weak Acid Weak Base The extent of this reaction is: fill in the blank 7 . A. ... Below 50% B. ... 50% C. ... Above 50% D. ... 100%

Answers

Answer:

c

Explanation:

What is the law of conservation or matter? Please helppppppp.....no links no trolling otherwise I'll report!
May give brainliest to first correct. :)

Answers

Answer:

In physics, a conservation law states that a particular measurable property of an isolated physical system does not change as the system evolves over time. Exact conservation laws include conservation of energy, conservation of linear momentum, conservation of angular momentum, and conservation of electric charge.

Explanation:

hope this helps :)

You have a solution of NaOH that is 3.0 M. If you need 250 mL of a 1.5 M solution, what volume of the stock solution should you use?

Answers

Answer:

answer is 30 g!!!!!!!!!

If x represents the molar solubility of Ca(OH)2 , what is the correct equation for the K sp ?

Ksp=x^2
Ksp=2x^3
Ksp=4x^3
Ksp=x^3

Answers

Answer:

Ksp = 4x³

Explanation:

Step 1: Write the reaction for the solution of calcium hydroxide

Ca(OH)₂(s) ⇒ Ca²⁺(aq) + 2 OH⁻(aq)

Step 2: Make an ICE chart

Let "x" be the molar solubility of calcium hydroxide.

        Ca(OH)₂(s) ⇒ Ca²⁺(aq) + 2 OH⁻(aq)

I                                 0                  0

C                              +x               +2x

E                                x                 2x

Step 3: Write the expression for the solubility product constant (Ksp)

The solubility product constant is equal to the product of the concentrations of the products raised to their stoichiometric coefficients.

Ksp = [Ca²⁺] × [OH⁻]² = x × (2x²) = x × 4x² = 4x³

if [tex]x[/tex] represents the molar solubility of  calcium hydroxide then  correct equation for the Ksp is [tex]\bold {x^3}[/tex]

Solubility product constant Ksp:

It is the equilibrium constant for a solid substance that are dissolved in an aqueous solution. It expresses how much a solute is dissolved in solution.

   

The reaction of calcium hydroxide for the solution  

[tex]\bold {Ca (OH )_2(s) \rightarrow Ca^2^+(aq) + 2 OH^-(aq)}[/tex]  

1 mole of calcium hydroxide is dissociate into 1 mole of calcium ion and 2 moles of Hydroxil ion.

The Ksp equation for the solution,

[tex]\bold {Ksp =[Ca^2^+][ OH^-]^2}\\[/tex]

If [tex]x[/tex] represents molar solubility,

[tex]\bold {Ksp =[x][ x]^2 = x^3}\\[/tex]

Therefore, if [tex]x[/tex] represents the molar solubility of  calcium hydroxide then  correct equation for the Ksp is [tex]\bold {x^3}[/tex]

To know more about Ksp,

https://brainly.com/question/4736767

Part
A certain gas is present in a 110 L cylinder at 2.0 atm pressure. If the pressure is increased to 4.0 atm, the volume of the gas
decreases to 5.5 L. Find the two constants k. the initial value of k, and kr, the final value of k, to verify whether the gas obeys Boyle's
law.
Express your answers to two significant figures separated by a comma.
View Available Hint(s)
ΤΟ
ΑΣΦ
t
2) ?
k ke =
Submit

Answers

Answer:

See explanation

Explanation:

Recall that from Boyle's law;

Volume is inversely proportional to pressure at constant temperature

V α 1/P

V = k/P

k = PV

Hence, for Boyle's law, PV = constant

In the first case;

P = 2.0 atm , V= 110 L

PV = 110 * 2.0 = 220

In the second case;

P = 4.0 atm , V= 5.5 L

PV = 4.0 * 5.5 = 22

Since PV is not constant in both cases, the gas does not obey Boyle's law.

copper chloride reacts with magnesium but magnesium chloride does not react with copper. Why is this?​

Answers

Answer:

Mg is highly reactive as compared to that of Copper owing to its periodic position

Explanation:

MG lies in the second column of the periodic table while Cu lies in the 11th column of the periodic table from the left.

The elements in the first two columns are metallic in nature are highly reactive.

In CuCl2 solution, Mg being highly reactive replaces Cu but in MgCl2 solution, Cu being less reactive in nature do not replaces the Mg from the solution.

What mass of Na2SO4 (sodium sulfate) is needed to make 2.5 L of 2.OM
solution?
O 1789
O 2849
O 7109
O 356 g

Answers

710 G hope it helps!

What product(s) would be formed when these are the reactants? C5H12 + O2 (limited)

Answers

Answer:

Carbon dioxide and water I believe because it is a combustion reaction

A _________________ is the path of energy transfer from producer to consumers.
Someone please help

Answers

Answer: Food chain

Explanation: none

The oceanic crust is mostly associated with the —————.

A. Thermosphere
B. Hydrosphere
C. Asthenosphere
D. Volcanoesphere
E. Atmosphere

Answers

i think it would the hydrosphere

Most acids are strong acids.

A. True
B. False

Answers

Answer:

False, There are only a few strong acids, so many people choose to memorize them. All the other acids are weak

Explanation:

False because most acid is not actually an strong acid for example grapes

Large cities in the U.S. often formed near the ocean.
What benefit does the ocean provide for people in nearby large cities?

Answers

Answer:

a means of work

Explanation:

since its near oceans they are closer to the fish

take it before its gone​

Answers

Hello my friend thank you
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