The mass after 16.042 days : 1.4 g
Further explanationGiven
mass of 5.6 gram sample of I-131
time=16.042 days
Required
The mass of a sample
Solution
General formulas used in decay:
[tex]\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{t/t\frac{1}{2} }}}[/tex]
T = duration of decay
t 1/2 = half-life
N₀ = the number of initial radioactive atoms
Nt = the number of radioactive atoms left after decaying during T time
Half-life of I-131 = 8 days
Input the value :
[tex]\tt Nt=5.6.\dfrac{1}{2}^{16.042/8}\\\\Nt=\boxed{\bold{1.4~g}}}[/tex]
Which substance can be decomposed by a chemical change?
A. Sodium, Na
B.Sulfur, s
C. Calcium Chloride, CaCl2
D.Argon, Ar
Answer:
It could be C. Calcuim Chloride.
Explanation:
Foods that are basic can be identified
by what taste?
astr
A. Salty
B. Sour
C. Bitter
D. Sweet
Answer:
sour!
Explanation:
can yall help w this? iss times so try nd hurry :P
Answer:
The first option
Explanation:
No new compounds were added, and the pre existing ones wern't changed, so option one is the only one that makes sense.
Good luck!
Can someone help me with the answer because I'm not good with chemistry
Three common gaseous compounds of nitrogen and oxygen of different elementary composition are known: (A) laughing gas containing 63.65% nitrogen, (B) a colorless gas containing 46.68% nitrogen, and (C) a brown toxic gas containing 30.45% nitrogen. Show how these data illustrate the law of multiple proportions.
Answer:
Please find how these data prove the law of multiple proportions below
Explanation:
The law of multiple proportions was proposed by an English chemist called John Dalton. The law states that when two elements combine and to form more than one compound. The weights/masses of the second element in the two compounds, which combines with a fixed ratio of the first element, is in a simple whole number ratio.
In this question, Nitrogen is said to combine with oxygen to give three different compounds as follows:
A) laughing gas containing 63.65% nitrogen i.e. 0.6365g
This means that the mass of oxygen will be (1-0.6365) = 0.3635g
B) colorless gas containing 46.68% nitrogen i.e. 0.4668g
This means that the mass of oxygen will be 0.5332g
C) brown toxic gas containing 30.45% nitrogen i.e. 0.3045g
This means that the mass of oxygen will be 0.6955g
The ratios of oxygen in the three compounds is therefore:
0.3635: 0.5332: 0.6955
Divide this ratio by the smallest number (0.3635)
0.3635/0.3635 = 1
0.5332/0.3635 = 1.467
0.6955/0.3635 = 1.913
Multiply this ratio by 2, we have:
2: 2.9 : 3.8
Hence, the simple whole number ratio is 2:3:4.
This proves the law of multiple proportions that oxygen is in simple whole number ratio in the three different compounds.
does lithium lose or gain valence electrons? and how much?
Which of these is a chemical property of a substance?
Compressibility
Ductility
Reactivity
Size and shape
Answer:
Reactivity
Explanation:
Answer:
Reactivity
Hope This Helps!!!
atomic weight of nitrogen,aluminium and calcium
Answer:
Atomic weight of(N) nitrogen is 14.0067
(Al)Aluminium is 26.98154
(Ca) calcium is 40.48
Explanation:
I hope it's helpful!
how does air pressure changes with altitude - the distance from the surface
Answer:At higher elevations, there are fewer air molecules above a given surface than a similar surface at lower levels. ... Since more than half of the atmosphere's molecules are located below an altitude of 5.5 km, atmospheric pressure decreases roughly 50% (to around 500 mb) within the lowest 5.5 km.
Explanation:brainliest plz
Answer:
What is that?
Explanation:
I need a answer quick. PLEASE
What is the volume of 2.43 x 1023 molecules of N2 gas at STP?
If a person is sterile, he or she is:
unable to reproduce
unable to complete meiosis
unable to complete a Punnett square
unable to complete mitosis
Answer:
1
Explanation:
Sterile means sperm or eggs are not able to Technichaly Create or produce.
What gases do scientists think may have been in the early atmosphere? *
When you lie down on a mattress the force of ______ pulls your mass towards the floor, while the force of the mattress pushes back up resulting in _______ forces, which allow you to sleep comfortably.
Answer:
1 gravity 2 counteractive
Explanation:
If the height that an object is dropped is increased, the object will bounce higher and therefore have
Answer:
Greater impact
Explanation:
Not only will it have a greater impact, but it will also have a greater risk of permanently deforming since the impact force can overcome the elastic modulus of the material and thus suffer permanent damage.
Phase of matter found in the sun and stars
Solid
Liquid
Gas
Plasma
Answer:
Your answer is Plasma which is D.
Explanation:
This is because lighting can be structed in the sky near stars or sun.
The formula that forms when Magnesium and Permanganate bond
2 of 4 examples as to why humans are the most dangerous creatures in the ocean
Answer
We kill animals and we are creul :)
Explanation:
Your welcome
Need help urgently!!
If samples of two different elements each represent one mole,
a
heir molar masses are equal.
b
they contain the same number of atoms.
c
they are equal in mass.
d
they have the same atomic mass.
Answer:
it's-D...........................
The time it takes the Moon to go from new moon to full moon and back to new moon is about
Answer:
it takes about 29.5 days for the moon to complete a cycle
Aluminum reacts with oxygen to produce aluminum oxide. If I give Tanya 3.2 grams of aluminum, how many g of oxygen does she need??
Al + O2 ---》 Al203
I wrote it out as it was easier to visualise that way, youll need to tap to see the full pic. feel free to comment if u have qns :)
Regan has an empty glass cup. It has a mass of 0.3 kg. She drops the cup on the ground and it shatters into several pieces. If she collected all of the pieces of the cup, how much mass would all of the pieces have combined?
A.
There is no way to determine the mass of the shattered glass.
B.
more than 0.3 kg
C.
less than 0.3 kg
D.
exactly 0.3 kg
Answer:
743456478697
Explanation:
Answer:
Exactly 0.3 kg
Explanation:
This is the right answer
What has occurred?
an endothermic reaction
an energy formation
a chemical reaction
a precipitate formation
The Statue of Liberty is made out of copper and was once shiny and copper-colored. Over the years, the copper has gone through a process called oxidation, where it has changed into a new material.
Answer:
a chemical reaction
Explanation:
What has happened to the statue of liberty is that a chemical reaction has occurred to the materials making up this edifice.
The statue is made up of copper. On reacting with oxygen, it undergoes an oxidation.
This makes the copper to rust and decolorize.
It implies that copper has reacted with oxygen in air and possibly from water.
This gives a new product.
We know this because for most chemical changes, they give new products and are not easily reversible.
show work on how you converted them. (also marking brainliest) <3
explanation for qn:
when converting units, u can show your working in the form
37.5 × 1g/1ml, then convert the g and ml into 1/1000 kg and L, and calculate from there. In the end, u find out its actually a trick qn and 1g/ml = 1 kg/L
Question 11 (5 points)
The following equation is balanced correctly:
Li + 02 --> Li20
O True
False
Answer:
False
Explanation:
On the left side of the equation (Li + O2), there is 1 Li atom and 2 O atoms.
but on thw right side of the equation (Li2O,) there is 2 Li atoms and 1 O atom
Dis fo chem try n answer it ig.
in the food web above which organism has the least amount of energy available?
A. caterpillar
B. Squirrel
C. Fox
D. Shrubs
In a 5.609g of H20, how many molecules H20
arc
present?
Answer:
1.88 x 10²³molecules of H₂O
Explanation:
Given parameters:
Mass of H₂O = 5.609g
Unknown:
Number of molecules of H₂O = ?
Solution:
To solve this problem, we need to find the number of moles of given compound first.
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Molar mass of H₂O = 2(1) + 16 = 18g/mol
Number of moles = [tex]\frac{5.609}{18}[/tex] = 0.31mole
From mole concept;
1 mole of a substance contains 6.02 x 10²³molecules
0.31 mole of H₂O will therefore contain 0.31 x 6.02 x 10²³molecules
= 1.88 x 10²³molecules of H₂O
CH3CH = CHCH3 *
A. alkane
B. alkene
C. alkyne
Answer:
B
Explanation:
when present
double bond the copound is alkene
What is compost manure? Explain.
Answer:
Compost is a mixture of organic residues (manure, animal carcasses, straw, etc.) that have been piled, mixed and moistened to undergo thermophilic (high heat 113 to 160 degrees Fahrenheit) decomposition (SSSA, 1997).
Explanation:
What is the working of fuse ?
Answer:
The interpretation of the frame of reference in question is demonstrated below.
Explanation:
The fuses operate on the assumptions including its heating temperature increase of the power supply. It consists of a single layer strip as well as a tangle of a metal rod or wire with such an, especially non-substance. These were directly linked to the finishes of that same access points. Fuse has always been hooked up to an electrical sequence connection.
