1. A 50 gram sample of a radioisotope decays to 12.5 grams in 14.4 seconds. What is
the half-life of this isotope?

Answers

Answer 1

Answer:

Half life = 7.2 seconds

Explanation:

[tex]from \: decay \: equation \\ 2.303 log( \frac{n.}{nt} ) = kt \\ 2.303 log( \frac{50}{12.5} ) = k \times 14.4 \\ k = \frac{2.303 log( \frac{50}{12.5} )}{14.4} \\ k = 0.096288 {s}^{ - 1} \\ since \: half \: life = \frac{ ln(2) }{k} \\ half \: life = \frac{ ln(2) }{0.096288} \\ half \: life = 7.2 \: seconds[/tex]

Answer 2
14.2 because basically you just divide it by 2 which would be half of it

That will work with all of those problems

So if it’s is a quarter of an isotope you’d divide by 4

Related Questions

HELP IN 8TH GRADE ADV SCIENCE

Answers

Answer:

protons: 36

neutrons: 48

electrons: 36

do all-stars mak energy through fusions

Answers

Yes they do make stars through fusions

Choose all that are correct about the elements in the column highlighted in blue
in the periodic table below (there are FOUR correct answers)

help !!!

Answers

Answer:

running a business is the best i have ever done to make a good friend of yours to get to the point where you have a lot to say

ill attach a picture​

Answers

Answer:

35.50

Explanation:

There are two stable isotopes, 35Cl (75.77%) and 37Cl (24.23%), giving chlorine a standard atomic weight of 35.45

what is the correct name for the compound MgBr?

Answers

Answer:

Magnesium bromide

Explanation:

its just the answer give brianliest

Elements in group 17 want to lose seven valence electrons and elements in group 1 want to gain seven valence electrons to become stable ions.

Answers

Because the halogen elements have seven valence electrons, they only require one additional electron to form a full octet. This characteristic makes them more reactive than other non-metal groups. hope it helped

If a parent cell has 24 chromosomes , how many chromosomes will each daughter cell have? Then compare the chromosomes in the parent cell and the daughter cells.

Answers

Answer:

If a cell has 24 chromosomes before cell division then daughter cell resulting from mitotic division will have 24 chromosomes while daughter cell resulting from the meiotic division will contain 12 chromosomes each.

Explanation:

what everyday things turn green because acid

Answers

Coins or anything copper

Explanation
They are everyday objects that turn green.

The measure of the speed of the moving or
vibrating particles is called the

Answers

Answer:

Temperature

Explanation:

It's called temperature.

This is because, in any substance an increase in temperature means that the particles on the average will move with greater speeds, or that they have greater kinetic energy while a decrease in temperature means that the particles on the average will move with lesser speeds, or that they have lesser kinetic energy.

why is water considered a pure substance?

a. each water molecule is identical

b. water can be broken down by physical means

c. water molecules are made up of different types of atoms

d. water can be combined with other substances by physical means

heLp ​

Answers

um i think its A or C

The more variation in a species, the less likely the chance that species has of surviving. true or false

Answers

Answer:

The more variation in a species, the less likely the chance that species has of surviving. false

Explanation:

As species have heritable variation the species produce more offsprings that can survive and offsprings within a favorable variation are more likely to survive and reproduce. Hence favorable variation makes the species diverse and more in population. Thus greater are the chances of survival, a decrease in diversity will lead to a decline in variability, and fewer chances of survival.

Please help me choose the correct statement

Answers

The ball has more mass because it weights more it may be less dense but more weight is being added to it

which is more reactive between magnesium and sulphur?​

Answers

Answer:

Sulfur (in British English: sulphur) is a chemical element with the symbol S and atomic number 16. It is abundant, multivalent and nonmetallic. Under normal conditions, sulfur

How to balance:


_N2+__O2+__H2O-> _HNO3



Answers

Answer:

2N2 + 5O2 + 2H2O → 4HNO3

Explanation:

Dinitrogen - N2

N₂ Nitrogen Gas Nitrogen Diazyne

Molar Mass of N2 Bond Polarity of N2

Dioxygen - O2

O₂ Oxygen Molecular Oxygen Diatomic Oxygen Triplet Oxygen Oxygen Gas Liquid Oxygen LOx

Molar Mass of O2 Bond Polarity of O2

Water - H2O

Dihydrogen Monoxide Dihydridooxygen [OH2] HOH Hydrogen Hydroxide Dihydrogen Oxide Oxidane Hydrogen Oxide

Molar Mass of H2O Oxidation State of H2O

Products

Nitric Acid - HNO3

Spirit Of Niter Fuming Nitric Acid Aqua Fortis Engravers Acid Hydrogen Nitrate HONO2 Peroxynitrous Acid [NO(OOH)]

Molar Mass of HNO3 Oxidation State of HNO3

A chemical reaction that has the general formula of AB + C → CB + A is best classified as a
synthesis
polymerization
decomposition
oxidation
replacement
reaction.

Answers

Replacement  reaction.

Further explanation

Given

A chemical reaction

AB + C → CB + A

Required

reaction type

Solution

There are several types of reactions that can occur

synthesis: 2 elements combine to form a single product

polymerization: monomers combine to produce a polymer

decomposition: One compound breaks down into 2 components

oxidation : a change in oxidation number

replacement can be divided into 2

single replacement if one element replaces the other elements of a compound

double replacement if there is an ion exchange between two ion compounds in the reactant to form two new ion compounds

AB + C → CB + A

If we look at this reaction, element C replaces element A to form a new compound CB. So it is single replacement. But this reaction can also be said to be an oxidation-reduction reaction because there is a change in oxidation number

element A undergoes a reduction reaction

element C undergoes an oxidation reaction

So types of redox reactions can be combination, decomposition, displacement, combustion, and disproportion.

Answer:

oxidation

Explanation:

i passed and got 100%

Liam observed that the pyrite looks like metal. what property did the student investigate?

Answers

Answer:

The correct answer is - Luster.

Explanation:

Luster is a property that explains how the light is reflected on the surface of a mineral. Luster can be categorized with the help of if an element or mineral is metallic or non-metallic.

Pyrite has a shiny, opaque metallic luster which is similar to other metals. There are different types of luster other than metallic also found like, silky, dusty, pearly, waxy, and a few more.

How many moles of Gold (Au) are in 3.60x10-5 g?
Choose the correct set up from the given choices.

a. .000360g divided by (196.96g/1 mol)

b. .0000360 g multiply by (1mol/196.96 g)

c. .00360 g divided by (1mol/196.96 g)

d. .0000360 g divided by (1mol/196.96 g)

Answers

Explanation:

[tex](.0000360 gAu} )\frac{1molAu}{196.96gAu}= ? mol Au[/tex]

The answer is d. .0000360 g divided by (1mol/196.96 g)

Identify and describe the processes that change rock below Earth's surface.

Answers

Answer:

crystallization, metamorphism, and erosion and sedimentation.

~+lil more info+~

The three processes that change one rock to another are crystallization, metamorphism, and erosion and sedimentation. Any rock can transform into any other rock by passing through one or more of these processes. This creates the rock cycle.

If you start with 3 moles of sodium and 3 moles of chlorine to produce sodium chloride, what is the limiting reagent?(You will need to balance
the equation first.)
Na + Cl2 -> NaCl A. They are equal B. Na C. Cl2 D. NaCl

Answers

Answer:

B. Na

Explanation:

Once balanced you get 2Na + Cl₂ ⇒ 2NaCl. Sodium is the limiting reagent because it would produce the smallest amount of the product (NaCl)–while chlorine is the excess reagent. Based off of the Na in the balanced equation, it would produce 3 moles of NaCl, and for Cl₂ it would produce an excess of 6 moles of NaCl. [It'd be wise to utilize stoichiometric factors to get a good grasp of this]

Why does soap work to remove oil? (Note that most oils can be considered non-polar. A soap molecule has one end that is polar and one end that is non-polar.)

Answers

Answer:

Soap breaks up the oil into smaller drops, which can mix with the water.

Explanation:

This works because soap is made up of molecules with two different ends.

The soap molecules works as a surfactant for the water oil interphase. The hydrophobic head of the soap molecules trap the oil and dirt ad remove from the surface.

What are surfactants?

Surfactants are chemical substances used to reduce the interfacial tension between substance boundary. Soaps and detergents acts as surfactants which are used to remove the dirt and oil from material surface.

Soap has both polar and non-polar characteristics. The alkaline part  in the soap causes it to have a polar head, and because of the electric charge on this head, the soap is hydrophilic. A hydrophilic part of soap is drawn to water and will cling to it.

In this instance, the positive-charged hydrogen atoms of the water's hydrogen atoms match with the polar head of the soap molecule. The other part of soap is a fatty acid tail, which is hydrophobic and can bind with the oil and dirt. The trapped oil molecules are then be removed by water.

To find more on surfactants refer here:

https://brainly.com/question/3062579

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_____is the chemical bond formed when two atoms share electrons.

Answers

Answer:

covalent bond

Explanation:

Answer:

The covalent bond is the chemical bond formed when two atoms share electrons.

Test Yourself
1- Which is larger:
a) Million or billion?
b) A part of million or a part of billion?
2- Which is more harmful: concentration of a poisonous substance (lead) in
drinking water to be a part of a billion or a part of a million?

Answers

Answer:

billion is larger \ part if billion

HELP PLEASE ASAP :)

What is the purpose of a salt bridge?
O.
A. To supply energy for the reaction
B. To connect two electrodes
O C. To prevent charge buildup
O D. To dissolve metals into solution

Answers

Answer: B. To connect two electrodes

Explanation:

The salt bridge forms a connecting link between the two electrodes. The function of the salt bridge is not to supply electrons from one electrolyte to another but to maintain a constant balance of charge as the electrons move from one half of the cell to the another. The electrons from from negative electrode to positive electrode that is from anode to cathode.

Answer: C. To prevent charge buildup

Explanation: I just took the quiz.

Specifically critique your personal impact on the changing climate.

Answers

Answer:

We can no longer ignore the fact that the world's climate is becoming more unpredictable and more extreme. As water levels rise, the risk of flooding looms large. At the same time, periods of drought are becoming longer and more frequent. Yet, our most precious resource – our planet's biosphere – is not only under threat. It is also the source of many of our solutions. Green Climate Solutions is the Wageningen Environmental Research programme that applies our understanding of nature and natural processes to address the challenges of climate change.

You discovered a new compound with the following formula: H(O) Pe. Using the information below, what would be the correct name for this compound?
*H(O) is an Alkaline Earth Metal.
*Pe is classified as a Halogen.

Answers

Answer:

Home personide.

Explanation:

In relation of Magnesium and Chlorine, MgCl2 is called Magnesium chloride

What is the rise in sea level between 1930 and 2003?
A)
About 20cm
B)
About 16cm
C
About 12cm

Answers

Answer:

about 16

Explanation:

its 20 - ( approximately 5)

= approximately 16

Answer:

It should be (C) about 12cm

Is 2AgNO3 + BaCI2 -> 2AgCl + Ba(NO3)2 Balanced or unbalanced. If unbalanced which element cause the unbalance

Answers

Answer:

This is balanced

Explanation:

Both sides contain 2 Ag 2 NO3 1 Ba and 2 Cl.

Describe each of the 3 main
domains used to classify living
things.

Answers

Answer:

Organisms can be classified into one of three domains based on differences in the sequences of nucleotides in the cell's ribosomal RNAs (rRNA), the cell's membrane lipid structure, and its sensitivity to antibiotics. 3. The three domains are the Archaea, the Bacteria, and the Eukarya.

Explanation:

Which of the following has the highest ionization energy?
a. F or I
b. Fr or C
c. Ne or Bi
d. Kor Kr
e. Ar or Mg

Answers

Answer:

helium

The first ionization energy varies in a predictable way across the periodic table. The ionization energy decreases from top to bottom in groups, and increases from left to right across a period. Thus, helium has the largest first ionization energy, while francium has one of the lowest.

Explanation:

hope it helps, mark brainliest please

What is the mass of .550 mL of alcohol (density = 82.0 g/mL)

Answers

Answer:

1.223 g/ml

Explanation:

45.1 ml of alcohol. Multiply 82 by .55 because it’s less than 1 ml
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