Iron-55 has a half-life of 3 years. How much of a 40 gram sample will remain after 12 years? A. 0 grams B. 4 grams C. 2.5 grams D. 20 grams

Answers

Answer 1

Answer:

[tex]\boxed {\boxed {\sf C. \ 2.5 \ grams }}[/tex]

Explanation:

We are asked to find how much of a 40 gram sample remains after 12 years.

Iron-55 has a half-life of 3 years. Therefore, after 12 years, 4 half-lives have been completed.

12 years/3 years = 4 half-lives

Every time a half-life is completed, half of the sample's mass decays. Remember we start with a 40 gram sample.

1 half- life: 40 g / 2 = 20 g 2 half-lives: 20 g / 2= 10 g 3 half-lives: 10 g / 2 = 5 g4 half-lives: 5 g / 2 = 2.5 g

There is also a formula that can be used to solve this problem.

[tex]A= A_o(\frac {1}{2})^{\frac{t}{hl}[/tex]

Where A₀ is the initial amount, t is the time, and hl is the half-life.

We know 40 grams is the inital amount, 12 years is the time, and 3 years is the halflife.

A₀= 40 g t= 12 hl= 3

[tex]A= 40 \ g (\frac{1}{2})^\frac{12}{3}[/tex]

[tex]A= 40 \ g (\frac{1}{2})^4[/tex]

[tex]A= 40 \ g * 0.0625[/tex]

[tex]\bold {A= 2.5 \ g}[/tex]

After 12 years, 2.5 grams of Iron-55 will remain.


Related Questions

answer these two please

Answers

the answer to question one is a dissecting microscope.
The answer to question two is the third option about three-dimensional images

what do you mean by acrophobia and ephebiphobia?​

Answers

Answer:

Acrophobia ------- intense fear of heights

Ephebiphobia -----the fear of youth

Answer:

Acrophobia means extreme or irrational fear of height .Ephebiphobia is the fear of youth

hope your day goes great.

The corpus callosum separates the brain into two halves. separates the brain into two halves. is a large network of neurons on the cerebral cortex. is a large network of neurons on the cerebral cortex. is a thick band of neural fibers enabling communication between the two brain hemispheres. is a thick band of neural fibers enabling communication between the two brain hemispheres. describes the hemispheres of the brain

Answers

Answer:

is a thick band of neural fibers enabling communication between the two brain hemispheres.

Explanation:

A brain can be defined as an organ of soft nerve tissue that is found in the skull of vertebrates and it's typically responsible for the coordination of nervous activities, intellect and sensation.

The human brain consists of various sections and these includes;

I. Anterior Cingulate Cortex (ACC) which resembles a bow or collar surrounding the frontal part of the corpus callosum. This is the frontal part of the cingulate cortex which helps to make complex cognitive functions such as impulse control, decision-making, emotions and empathy.

II. Ventral prefrontal cortex in humans are interconnected with the brain and are responsible for the processing of risk, empathy, fear and social decision-making

III. The Cerebral Cortex: this part of the brain primarily comprises of grey matter, foldable sheets of neurons and forms its outermost layer. Therefore, cerebral cortex is known as the outermost layer of the brain (cerebrum) and thus, makes up half of its weight. It is about 2.5 millimeters in thickness and as such it's able to fold.

The corpus callosum is a large, thick band of C-shaped neural fibers found beneath the cerebral cortex and it's saddled with the responsibility of enabling communication between the two brain hemispheres i.e the right hemisphere and the left hemisphere.

can someone please help with this urgently.

you don't have to explain, just answer ​

Answers

Answer:

B. option A 2 daughter cells

C. option D metaphase

Answer:

Q1 B

Q2 D

Q3  D

Q4 D

Explanation:

A zombie apocalypse wipes out almost the entire human species before the zombie threat is eliminated. It appears that only a group of 100 people who were at a family reunion on an uninhabited island survived. They returned to the mainland completely unaware of what had happened to everyone. Answer the following questions regarding the few survivors that now begin to rebuild the human population.

Certain traits will have been lost from the gene pool forever. Some may be obvious, like people with red hair and double jointed thumbs. Others will be less obvious, like the ability to process cholesterol or being allergic to peanuts.

a.) Which of the following best describes the mechanism of microevolution that has altered the human gene pool? Explain.

b.) Despite an abundance of habitat, why will it be difficult for the human species to recover in numbers?

c.) A straggler with green eyes stumbles into the last remaining human outpost. The green eye trait did not exist in the outpost before her arrival, but it does now. What is the name of this mechanism of evolution? Explain.

Answers

Answer and Explanation:

A. Hello. You did not enter answer options. However, we can state that mutation, natural selection and genetic drift will be the microevolution mechanisms that will affect the gene pool of these humans. This is because the new environment and the small number of living beings, will make this population completely susceptible to all these evolutionary factors, which will affect, in different ways, the gene frequencies in a population.

B. As the amount of living beings and human beings has become very small, the world will have a low genetic diversity. This will make it difficult for these humans to adapt to the new environment and will make them more susceptible to possible diseases that will arise in this new environment. This will make these humans more fragile and make it harder for them to multiply.

C. The evolution mechanism is the Gene Flow. Gene Flow refers to the exchange of genetic information between individuals in a population, through the donation of gametes that occur in reproductive processes. In this case, we can consider that the individual with green eyes, upon arriving in the community with individuals without green eyes, began to reproduce descendants, who, upon receiving the gametes responsible for green eyes, began to populate this community with this characteristic.

Which is a molecule found in the body?
O urethra
O nutrients
O atoms
O water

Answers

Answer:

water

Explanation:

Answer:

Water

Explanation:

Match the following STDs with their descriptions. 1. can cause sores, rashes, dementia, or blindness gonorrhea 2. can cause burning urination and infertility chlamydia 3. similar to gonorrhea but more likely to be carried unknowingly syphilis 4. parasitic STD causing genital irritation and mild discharge 5 crabs 5. pubic lice that cause itching trichomoniasis 6. untreatable STD causing periodic outbreaks of blisters 1 HPV 7. can cause genital warts or cervical cancer 6 genital herpes

Answers

Answer:

1. Syphilis

2. Gonorrhea

3. Chlamydia

4. Trichomoniasis

5. Crabs

6. Genital herpes

7. HPV

Explanation:

STD is an acronym for sexually transmitted disease and it can be defined as diseases that are easily transmissible or contractable from another person through sexual intercourse. Thus, STD spread from an infected person to an uninfected person while engaging in unprotected sexual intercourse. Some examples of STDs are gonorrhea, chlamydia, syphilis, HIV, HPV, etc.

Generally, contracting STDs has a detrimental effect to a patient because it causes an opening (break) or sore in the body of the carrier (patient) and as such making them vulnerable to diseases that are spread through bodily fluids e.g human immunodeficiency virus (HIV), Hepatitis, staphylococcus, AIDS, etc.

1. Syphilis: can cause sores, rashes, dementia, or blindness.

2. Gonorrhea: can cause burning urination and infertility

3. Chlamydia: similar to gonorrhea but more likely to be carried unknowingly

4. Trichomoniasis: parasitic STD causing genital irritation and mild discharge.

5. Crabs: pubic lice that cause itching.

6. Genital herpes: untreatable STD causing periodic outbreaks of blisters

7. HPV: can cause genital warts or cervical cancer. HPV is an abbreviation for human papillomavirus and it's a virus that causes most common sexually transmitted infection, giving rise to skin or mucous membrane growths (warts).

Answer:

1) syphilis

2) gonorrhea

3) chlamydia

4) trichomoniasis

5) crabs

6) genital herpes

7) HPV

Plant
cell can be identified by the process of
A) Choloroplast
B) plasma membrana
c) cell wall
D)Mitochondria
A )i and ii (B) i and iii
(c) ii and iii (0) iv only​

Answers

Explanation:

i think it is choloroplast

the answer is A, chloroplast.

The following illustration shows a food web for a kelp forest off of the coast of California. What do you predict would happen to the kelp population if the sea otter population declined?




The kelp population would decrease: sea otters eat urchins, and urchins eat kelp.

The kelp population would increase: sea otters eat urchins, but not exclusively.

The kelp population would remain unchanged; sea otters do not eat the kelp.

The kelp population would remain unchanged: sea otters eat urchins, but not exclusively.

Answers

Answer:

The kelp population would decrease: sea otters eat urchins, and urchins eat kelp.

Explanation:

The diagrammatic illustration in this question is showing a food web made up of a variety of species feeding on one another. As shown in the food web, sea otters are one of the top predators that can eat a wide variety of organisms.

Sea urchins feed directly on kelp, however, the population of sea urchins can be controlled by sea otters which feed on sea urchins. Hence, if population of sea otters declined, more sea urchins will be available to feed on the kelp population, hence, will DECREASE.

Answer:The kelp population would decrease: sea otters eat urchins, and urchins eat kelp.

Because the otter population decreases the urchin population increases and therefore the demand for kelp increases and the kelp population will decrease as the population of urchins increases and it feeds on the kelp and due to the reduction in otters there is nothing controlling the urchin population

Explanation: Took the test got it correct

Dose anyone know the answer

Answers

Answer:

Anthracite is the answer

What is the process that human
beings undergo to release ATP from
carbohydrates?
A. cell duplication
B. cellular genesis
C. cellular respiration
D. photosynthesis

Answers

Answer:

[tex]\huge\boxed{\sf Option \ C}[/tex]

Explanation:

Cellular respiration is the process in which carbohydrates (Glucose) are broken down into carbon dioxide and water in the presence of oxygen and a lot of energy is released which is further used for ATP synthesis and ATP is released!

[tex]\rule[225]{225}{2}[/tex]

Hope this helped!

~AH1807Peace!

¿Cuál es la importancia de la colonización de habitad para la ecología?

Answers

Answer:

i dont speak spanish so ya but thanks for the points

Explanation:

How do animals and people cause weathering?

How do plants cause weathering ?

Answers

Answer:

Plants can cause mechanical and chemical weathering

Explanation:

Plants can cause mechanical and chemical weathering. When plants cause mechanical weathering, their roots grow into rocks and crack them.It can also happen in streets or sidewalks. When plants cause chemical weathering, there roots release acid or other chemicals, onto rocks, which then forms cracks, and breaks apart.

Animal and plant mobility is a factor in biological weathering, for instance, a plant may grow in a gap in a rock and, as its roots spread, cause the fracture to expand.

What is the cause of weathering?

A rabbit may also burrow into a crack in a rock, making it wider and eventually separating the rock.

Animals and plants can act as mechanical weathering agents. In dirt that has gathered in fractured rock, a tree seed may emerge. The fissures get wider as the roots spread out, finally shattering the rock into pieces.

Even big rocks might get dislodged by trees over time, rocks are broken down by plants like moss that absorb their minerals.

Therefore, holding onto soil and rocks is another way that plant roots cause weathering, and might stop erosion.

Learn more about weathering, here:

https://brainly.com/question/17056344

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2) ¿Cuál de los siguientes hechos no es una evidencia de una reacción química? a) Presencia de un catalizador b) Cambio de color d) Liberación de gas​

Answers

Answer:

a) Presencia de un catalizador

Explanation:

Los dos tipos de cambios que experimentan las sustancias en la química son cambios químicos y físicos.

Un cambio físico es un cambio es un cambio en el que la sustancia cambia en su apariencia o su forma de una manera que es reversible y en la que no se forma una nueva sustancia.

Un cambio químico es aquel en el que hay un cambio en las sustancias presentes y se forma una nueva sustancia.

La evidencia de que ha tenido lugar un cambio químico incluye

1) La formación de un precipitado a partir de la mezcla de sustancias.

2) Un cambio en el color de las sustancias.

3) Un cambio en el olfato (que desprende un olor) o en el sabor.

4) La sustancia produce luz (brilla)

5) El volumen total cambia

6) Cambio de temperatura (la mezcla se calienta o enfría)

Por lo tanto, la presencia de un catalizador, que es una sustancia que no participa en una reacción pero aumenta la velocidad de reacción, no es evidencia de una reacción química.

What describes how individuals are distributed, or spread, throughout their habitat.

1: Population density
2: Population distribution

Answers

Population Distribution, mark brainliest if this helped!

What are the three examples to justify Newton first law of motion .​

Answers

1. A book sitting on top of a table
2. A soccer ball rolling on the ground
3. A person driving a car to a stop

How Can I Explain Why A Theory Is Also A Hypothesis?

Answers

Answer:

well a hypothesis is literally a scientific assumption or theory used to describe what they think is going to happen during a experiment

Economic impact of agricultural pollutants on water sustainability for agricultural production. summarise your findings in a table form​

Answers

Answer:

nalaqdua

Explanation:

sbospka ai9wlhzux5 s8fvekg

Which ocean borders the western coast of South America

Answers

Answer:

Pacific Ocean

Explanation:

here is your answer

The Pacific Ocean borders the western coast of south america

Answer me!!!!
Read the descriptions of two experiments below.
Experiment 1: A group of students did a test to see if the
acidity of water affects the growth of pea plants. They
followed a logical method and performed their experiment
once, using a control group and experimental groups. The
results supported their hypothesis.
Experiment 2: A group of students did a test to see if the
acidity of water affects the growth of bacteria in the water,
They used a control group and experimental groups. They
repeated their experiment several times and received the
same results each time.
Which experiment is more likely to be reliable, and why?
O A. Experiment 2, because it gave the same results every time
O B. Experiment 1, because its results supported the hypothesis
O C. Experiment 1, because it followed a logical method
O D. Experiment 2, because its setup included a control group

Answers

Answer:

A

Explanation:

Because it is giving you the same results ( i just did the test and got it right)

Answer:

a.

Explanation:

just took the test

Una especie de mariposa presenta rasgos fenotípicos diferentes entre los miembros de sus poblaciones. Estos rasgos van desde una coloración verdosa y antenas cortas (características recesivas). El fenotipo más común (características dominantes) de esta especie es de coloración amarilla y de antenas tan largas que se pueden doblar. Realice el cruce entre dos mariposas que presentan fenotipo más común, pero de genotipos heterocigotos y determine los posibles rasgos fenotípicos que se pueden presentar.

Answers

Answer:

can you please translate for us into English

A genetic factor for a trait is always expressed when it is present is best described as ?

Answers

Answer:

A genetic factor for a trait that is always expressed when it is present is best described as dominant.

OAmalOHopeO

Does cellular respiration follow the law of conservation of energy?

Answers

Yes. Every chemical reaction obeys the law of conservation of mass.

Believe it!!

Pls follow me.

is the presence of industry in developing nations high? what about developed nations?​

Answers

Answer:

Developing countries don't have lots of industries, so it's not high

Developed nations have a wide variety of industries

Explanation:

Binary Fission and Mitosis are similar processes. One way they are different is that: A. In Binary Fission, the DNA does not form into chromosomes. B. They both split by growing a new cell wall. C. In Mitosis, the DNA does not form into chromosomes. O D. Binary Fission only occurs in Eukaryotes.

Answers

Answer:

C. In Mitosis, the DNA does not form into chromosomes

ASAP
Identify the error in the following statement: “Photosynthesis is a chemical reaction that takes place in the chloroplasts of green plant cells, where light energy is used to convert glucose and water into carbon dioxide and oxygen.”
A. “glucose” and “carbon dioxide” should be switched
B. No errors
C. “water” and “oxygen” should be switched
D. “chloroplasts” should be “mitochondria”

Answers

I think its B the answer for your questions not sure
Hope u find it

Photosynthesis is a chemical reaction that takes place in the chloroplasts of green plant cells, where light energy is used to convert carbon dioxide and water into glucose and oxygen. Option A is the right answer.

What is photosynthesis?

Photosynthesis is the process by which green plants prepare their own nutrients with the help of sunlight, water, and carbon dioxide.

Photosynthesis helps plants to prepare their own food, these plans are called autographs.Photosynthesis takes place inside the protoplast.This process takes place in some other organisms other than green plants.Chlorophyll is the green pigment that is required for this process to take place.The end products that are formed in the process of photosynthesis are glucose and water.

Hence Option A is the right answer.

To learn more about photosynthesis, refer:

https://brainly.com/question/1388366

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Forces that act in pairs are said to be _____________.

A. Stable
B. Unbalanced
C. Unstable
D. Balanced

Answers

The answer is A, stable.

Suppose you traveled back in time and located the first animals to have evolved feathers. You found that these animals were tree-dwelling ectotherms, able to run quickly but unable to fly. You also noticed that only males had feathers. Which hypothesis of feather evolution would these data most support? Feathers initially evolved in a role associated with ________.

Answers

Answer:

Feathers initially evolved in a role associated with sexual selection.

Explanation:

In species where only males had feathers, these feathers can be considered to have evolved into a role associated with sexual selection. This is because in these species, males used their feathers as a sexual attraction for females, in this case, females chose the males that had more attractive feathers to mate and generate new individuals for the species. An example of this can be seen in the peacock, where the tail with lush feathers is only present in males and is intended to sexually attract females.

Which of the following is present in eukaryotes......
A) Cell wall B) Flagellum
C)Diploid nucleus D) membrane bounded organelles

Answers

D. membrane bounded organelles

Answer:

Membrane bounded organelles are present in eukaryotes..

Explanation:

hope it is helpful to

Plant roots are more easily able to absorb ammonium that has been produced from ________.

A. nitrification
B. nitrogen fixation

Answers

Plants roots are more easily able to absorb ammonium that has been produced from nitrogen fixation
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