Answers
Answer:
See detailed solution below
Explanation:
Now, let us solve each question step by step.
1) Given that;
N = amount of radioactive material at time t
No= amount of radioactive material originally present
t = time required for N amount of radioactive material to remain
t1/2= half life of the radioactive material
So,
N/No = (1/2)^t/t1/2
N/60 = (1/2)^22.8/3.8
N/60= (1/2)^6
N/60=1/64
64 N = 60
N = 60/64
N = 0.9 g
2) N/No = (1/2)^t/t1/2
N/8 = (1/2)^103.2/34.4
N/8 = (1/2)^3
N/8 = 1/8
8N = 8
N = 1 L
3) N/No = (1/2)^t/t1/2
50/No = (1/2)^18/6
50/No = (1/2)^3
50/No = 1/8
No = 50 * 8
No = 400 micrograms
4) N/No = (1/2)^t/t1/2
62.5/500 = (1/2)^26/t1/2
0.125 = (1/2)^26/t1/2
Since 0.125 = 1/8
1/8 = (1/2)^26/t1/2
(1/2)^3 = (1/2)^26/t1/2
Hence;
3 = 26/t1/2
t1/2 = 26/3
t1/2 = 8.7 hours
Related Questions
Which human activity can have the greatest positive effect on global climate change by helping to reduce the amount of carbon dioxide in the atmosphere
Answers
Answer:
C. Limiting internal combustion engines that power automobiles.
Explanation:
I majored in Chemistry
You are eating dinner with your familiy one night. Your little brother (Who is a disgusting monster ) asked if you likes "seafood?" When you said yes, He proceeded to show you his chewed up, or "See Food". Did a chemical reaction take place, yes or no? What evidence or lack of evidence do you have to support your answer?
Answers
Answer:
yes eating the food involves both physical and chemical changes. The chewing of food is a physical change, while the mixing of saliva with food triggers chemical reactions
Explanation:
Once the food mixes with the saliva in our mouth, chemical reactions start taking place in the food, leading to its breakdown and changes in its chemical composition. An evidence of the chemical changes is the taste that we feel when we eat something sweet or sour etc.
Answer:
a chechimal
Explanation:
determine the number of charged particles in nucleus of calcium atom then deduce the number of electrons
NUCLEAR CHARGE (20+)
ATOMIC MASS (40 amu)
given the relative charge of a proton =1+\ m1nucleon=1amu
Answers
Answer:
detail is given below.
Explanation:
The charged particles of nucleus are protons while neutrons are neutral having no charge.
We know that an atom consist of electrons, protons and neutrons. Neutrons and protons are present inside the nucleus while electrons are present out side the nucleus.
Electron has a negative charge and is written as e⁻. The mass of electron is 9.10938356×10⁻³¹ Kg . While mass of proton and neutron is 1.672623×10⁻²⁷Kg and 1.674929×10⁻²⁷ Kg respectively.
Symbol of proton= P⁺
Symbol of neutron= n⁰
The number of electron or number of protons are called atomic number while mass number of an atom is sum of protons and neutrons.
one proton contribute 1 amu to the total weight. There are 20 protons and 20 neutrons in Ca thus its atomic mass is 40 amu.
While the atomic number is 20.
the filament in an electric light bulb is made from a. platinum b. fiberglass c. aluminum d. tungsten
Answers
how do humans benefit from photosynthesis
Answers
Answer:
Explanation:
Without photosynthesis there would be no oxygen in the earth's atmosphere and we wouldn't be here!
I WILL DIE I HAVE A KNIFE IN MY HAND. ANSWER WITH EXPLANATION. If the sound is high pitched, then the wave's frequency would have a:
A.high frequency, short wavelength
B. high frequency, long wavelength
C. low frequency, long wavelength
D. low frequency, short wavelength
Answers
Answer:
A
Explanation:
High frequency, short wavelength
(Pls help i will give brainlyest) Label the missing parts of the diagram.
Answers
Answer:
Sedimentary rock
Metamorphic rock Igneous rock
The following compounds will
decompose on heating except
A Ag2CO3.
B. CaCO3.
C. K2CO3
D. PbCO.
E. ZnCO3
Answers
AnsThe option C is correct
which is a greater threat to a mountain ecosystem: a beetle that kills coniferous trees or a wolf thats hunts and eats deer?
Answers
Answer:
Explanation:
The mountain ecosystems are characterized by coniferous tree species such as pinus, firs, and spruces and species such as deers, bears, and wolves.
A beetle that kills coniferous trees would be a greater threat to the ecosystem than a wolf that hunts and eat deer because the dominant trees in the ecosystem are conifers. Hence, a beetle that kills coniferous trees might end up killing the dominant tree species in the ecosystem and this will gravely affect other plant and animal species within the ecosystem.
Wolves and deers have their niche in the mountain ecosystem already and hence, their populations are naturally limited by limiting factors of the environment. Hence, a wolf that hunts and eats deers would be of a lesser threat to the mountain ecosystem.
AB + energy→ A +B
23.
The general equation shown is a reaction that is an
a. exothermic decomposition
b. endothermic decomposition
c. endothermic synthesis
d. exothermic synthesis
Answers
Answer:
b. endothermic decomposition
Explanation:
Decomposition reaction:
It is the reaction in which one reactant is break down into two or more product.
AB → A + B
Synthesis reaction:
It is the reaction in which two or more simple substance react to give one or more complex product.
A + B → AB
Endothermic reactions:
The type of reactions in which energy is absorbed are called endothermic reactions.
In this type of reaction energy needed to break the bond are higher than the energy released during bond formation.
For example:
C + H₂O + 131 kj/mol → CO + H₂
Thus, in given reaction energy is added and AB compound is decomposed to give A and B so this reaction is endothermic decomposition.
What causes these H-bonds to form?
Answers
Answer: It is caused by the tendency of some atoms in molecules to attract electrons more than their accompanying atom.
What is this called? it might be sideways but it show look like a Y
Answers
Answer:
I'm thinking it might be Element 39: Yttrium, as this is Chemistry.
Explanation:
How is a scientific law different from other laws in society?
O A. A scientific law is a rule about how to treat and punish people.
B. A scientific law describes what always happens under specific conditions in nature. O C. A scientific law serves to protect people, property, and nature from harm.
O D. A scientific law is what scientists have decided should be forced to happen in nature.
Answers
Answer:
The answer will be A
Explanation:
A scientific law is based on repeated experiments or observations, that describe or predict a range of natural phenomena. A scientific law is something that is unexpected
Answer:
B
Explanation:
It just is.......
How would life be different if there were 10 hours in a day
Answers
Answer:
If there was only 10 hours in a day, including the night time it would be complexly new environment. Say you are up for 7 hours and sleep 3, in those 7 hours you would go to work for probably 4 hours, come home and do stuff for 3 then go to bed and do it all over again.
Does anyone know what Yttrium(II) Dichromate's formula would look like?
Answers
Answer:
YCr2O7
Explanation:
Please if you don't know don't answer
Answers
Answer:
Mass = 50kg, a = 20m/sec^2
F = MA
F = 50 * 20
F = 1000N
F = MA
650 = M * 10
M = 650/10 = 65kg
The phenomenon of weightlessness occurs when there is no force of support on your body. when your body is effectively in free fall, accelerating downward at the acceleration of gravity, then you are not being supported.
F = Gm1m2/distance^2
F = 6.6726* 10 ^-11 * 70 * 5.98 * 10^24/(6.38 * 10^6)^2
hope it helps you
What is the bond order for a single covalent bond?
Answers
Answer:
We typically represent covalent bonds with a dash ( - ) between the atoms. This indicates a single bond. Ex: Cl - Cl
Single bond, double bond, triple bond.
Explanation:
We call it a single covalent bond because the atoms are sharing a single pair of electrons.
Answer: If you have this question: The bond order for a single covalent bond is ____.
Then the answer is oneExplanation:
What is the only force that acts on a falling body when it is in free fall?
Answers
Answer:
Gravity
Explanation:
Objects that are experiencing free fall, are not encountering a significant force of air resistance or as a matter of fact any other kind of forces, they are falling under the complete control of gravity.
Which particle has no mass and no charge?
O alpha
O beta
gamma
O
neutron
Answers
Answer:
Neutrons
Explanation:
I NEED ANSWER ASAP Which of the following statements is true for a scientific theory? It is a well-tested hypothesis. It is verified by only one scientist. It is based on only one experiment. It is investigated over a short period.
Answers
Answer:
A.) It is a well-tested hypothesis.
Answer:
Its is a well-tested hypothesis
Explanation:
i took the test
Complete this sentence. If mass remains the same while the volume of a substance ________, the density of the substance will_______________.
(NOT GIVING BRAINLIEST, JUST ANSWERING A QUESTION MOST PEOPLE GOT WRONG ON)
A. decreases, decrease
B. increases, decrease
C. increases, stay the same
D. decreases, stay the same
**It's D**
Answers
Answer:
B. Increases, Decreases
Explanation:
I majored in Chemistry
Which sample contains the same number of atoms as a gram-atomic mass of He?
1.
6 g of C
2.
7 g of Li
3.
8 g of o
4.
9 g of F
Submit Answer
Answers
Answer: 2. 7g of Li
Explanation: A mole of any substance contains the same number of particles (Avogadro's number, 6.02*10^23). 1 gram atomic mass of He (4g) is equivalent to 1 mole; so is 1 gram atomic mass (7g) of Li
Can someone help please
Answers
Answer:
d. cells are made of atoms and molecules. :)
Explanation:
hope i helped
Which example shows how genetic engineering can be used in the agricultural industry?
A.
Two tomato plants that produce sweet tomatoes are crossed to produce offspring that also produce sweet tomatoes.
B.
A horse is bred with a donkey to produce a hybrid offspring that has characteristics of both parents.
C.
A gene for pest resistance is inserted into the genome of a corn plant.
D.
A sheep is cloned to produce an exact copy of the original sheep.
Answers
Answer:
c. a gene for pest resistance is inserted into the genome of a corn plant
Explanation:
Answer: A duh
Explanation:
becastse
A ball is moving at a speed of 6.70 m/s. If the kinetic energy of the ball is 3.10 J, what is the mass of the ball?
Answers
Answer:
0.14 kgExplanation:
The mass of the ball can be found by using the formula
[tex]m = \frac{2k}{ {v}^{2} } \\ [/tex]
v is the velocity
k is the kinetic energy
From the question we have
[tex]m = \frac{2(3.10)}{ {6.70}^{2} } = \frac{6.20}{44.89} \\ = 0.138115...[/tex]
We have the final answer as
0.14 kgHope this helps you
How does knowing the meaning of prefix-trans help you remember what happens to light that strikes a translucent object ?
Answers
Explanation:
The prefix trans- and its variant tra- mean "across".
A translucent substance allows some light to go "across" it to the other side. Also, think about a transparent substance: it allows light to go "across" it; or a translation, it is a going "across" from one language into another.
Ratan started business with cash Rs 50000
Answers
Answer:
what's the question here then ?????
Explanation:
nepal ????
On a roller coaster, where is maximum kinetic energy I’ll mark the brainiest.
Answers
Answer:
its the pink one I think
Explanation:
Answer: At the bottom of a big hill
how is wind energy captured?
where is wind energy found?
how is water energy captured?
where is water energy found?
plz use the passage i put. plz and thank you!!!!!
Answers
When glucose is totally oxidized to CO2 and H2O, how many ATP molecules are made by oxidative phosphorylation out of a maximum yield of how many ATP molecules?
Answers
Answer: 26 out of 30.
Explanation:
Out of 30 ATP molecules, 26 are produced from maximum oxidative phosphorylation production. Two more come from glycolysis and two more are from the citric acid cycle.
To power other cellular processes, ATP captures and releases chemical energy obtained from the breakdown of food molecules.