The amount remaining after 36 years is 5 g
How to determine the number of half-lives Half-life (t½) = 12 yearsTime (t) = 36 years Number of half-lives (n) =?n = t / t½
n = 36 / 12
n = 3
How to determine the amount remaining Original amount (N₀) = 40 gNumber of half-lives (n) = 3Amount remaining (N) = ?N = N₀ / 2ⁿ
N = 40 / 2³
N = 40 / 8
N = 5 g
Therefore, the amount remaining after 36 years is 5 g
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LAB: predicting products
Answer:
1) synthesis MgI2
2) double replacement CuS + (HCl)2
3) double replacement, not sure ab the formula sorry
what is conduction,convection,and radiation in science brainiest nice and great answer report wrong answer
Is water wet?
Seriously
Answer:
no its moist
Explanation:
Answer:
I say yes but my friends tell me that it's not because it makes things wet henceforth is not able to be "wet"
Explanation:
it is definitely wet though.
Hope this helps! :)
In lab, a student observes an unknown substance dissolve in water and its mass remains the same. Which law is the student thinking of
The law which this student is thinking of is the law of conservation of mass (LOCOM).
What is LOCOM?LOCOM is an abbreviation for the law of conservation of mass and it states that mass is neither created nor destroyed in any chemical reaction.
This ultimately implies that, the mass of any substance in a balanced chemical equation or chemical reaction would remain the same at the end.
According to the law of conservation of mass (LOCOM), the mass of all the reacting chemical elements of any substance must be equal (remain the same) to the mass of the product formed during a chemical reaction.
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a sample of (NH4)2SO4 contains 0.750 mole. what is the mass of the sample
the checkmarks on thus picture indicating the __________________ factors of an ecosystem
A)Aboiotic
B) biotic
Answer:
We need the picture to answer the question
Explanation:
but i did do this test and number 4 was biotic and number 5 was abotic hope this helped
How can you tell the difference between a rock and a mineral?
Answer:
Explanation:
a mineral would have other elemts in its mixture where as a rock would be more simple, the mineral if were to have a metalic element in it would attract magnets to it making it magnetic
Silicate minerals are subdivided into six groups based on the way silica tetrahedra are.
Answer:
The linking together of silica tetrahedra into chains that do not easily move
Explanation:
Answer:
arranged and bonded
Explanation:
silicate minerals are subdivided into six groups based on the way silica tetrahedra are arranged and bonded
HELP?? Read each statement and determine which characteristic each person is demonstrating. THE OPTIONS TO FILL IN THE "___" ARE, [Creative], [Curious], [Ethical], [Skeptical]
_____ Andrew asks questions about how the volcanoes in Hawaii were formed.
_____ Robyn sees a magazine for kids at the grocery store with an article about a new fossil discovery. So, she searches scientific journals that support the content of the article.
____ Maggie uses her knowledge of physics to create a simple machine for a science fair project.
____ Shaun is testing a new medication on animal subjects. He is sure to follow all guidelines for appropriate care and testing.
Answer:
1. curious
2. curious
3. creative
4. Ethical
Explanation:
I am not sure but I hope they are correct! :)
Answer:
Curious.)
Andrew asks questions about how the volcanoes in Hawaii were formed.
Skeptical.)
Robyn sees a magazine for kids at the grocery store with an article about a new fossil discovery. So, she searches scientific journals that support the content of the article.
Creative.)
Maggie uses her knowledge of physics to create a simple machine for a science fair project.
Ethical.)
Shaun is testing a new medication on animal subjects. He is sure to follow all guidelines for appropriate care and testing.
Explanation:
Have a great rest of your day
#TheWizzer
Which graph most likely represents a rabbit population that found a new, larger habitat, but then eventually experienced an increase in predation?
Graph A
Graph B
Graph C
Graph D
Answer:c
Explanation:
3 Cu + SHNO3 — 3 Cu(NO3)2 + 2 NO + 4 H20
In the above equation, how many grams of water can be made when 11.9 moles of HNO3 are
consumed?
Considering the reaction stoichiometry, the mass of H₂O that is produced when 11.9 moles of HNO₃ react is 107.1 grams.
Reaction stoichiometryThe balanced reaction is:
3 Cu + 8 HNO₃ → 3 Cu(NO₃)₂ + 2 NO + 4 H₂O
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
Cu: 3 molesHNO₃: 8 molesCu(NO₃)₂: 3 molesNO: 2 molesH₂O: 4 molesThe molar mass of the compounds present in the reaction is:
Cu: 63.54 g/moleHNO₃: 63 g/moleCu(NO₃)₂: 187.54 g/moleNO: 30 g/moleH₂O: 18 g/moleThen, by reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of mass of each compound participate in the reaction:
Cu: 3 moles ×63.54 g/mole= 190.62 grams
HNO₃: 8 moles ×63 g/mole= 504 grams
Cu(NO₃)₂: 3 moles ×187.54 g/mole= 562.62 grams
NO: 2 moles ×30 g/mole= 60 grams
H₂O: 4 moles ×18 g/mole= 72 grams
Mass of H₂O producedIt is possible to determine the the amount of mass of H₂O produced by a rule of three: if by stoichiometry 8 moles of HNO₃ produce 72 grams of H₂O, if 11.9 moles of HNO₃ react how much mass of H₂O will be formed?
[tex]mass of H_{2}O=\frac{11.9 moles of HNO_{3} x72 grams of H_{2}O}{8 moles of HNO_{3}}[/tex]
mass of H₂O= 107.1 grams
In summary, the mass of H₂O that is produced when 11.9 moles of HNO₃ react is 107.1 grams.
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Which describes an effect that ocean currents have on short-term climate change? Ocean currents increase the strength of prevailing winds, which can cool the air and land. Ocean currents can carry cold water, which can cool the air and land. Ocean currents increase hurricane activity, which can raise the temperature of the air and land. Ocean currents carry cold water, which may not affect hurricane activity and lower the temperature of the air and land.
The movement of the ocean and sea waves in a direction is called the ocean currents. Ocean currents can bring cold water, which cools the land and atmosphere.
What are the effects of ocean currents?Ocean currents are the movement of the oceanic waves by the influence of the gravitational forces that can affect the atmosphere and the climate of the region.
Oceanic currents are capable of carrying cold water from polar areas to the regions of the equator resulting in a cooling atmosphere over the geosphere.
Therefore, option B. oceanic currents carry colder air to the warmer regions.
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Answer:
B
Explanation:
Rank each of the molecules below in order of the shortest to the longest sulfur oxygen bond length a.SO2 b.SO3^2- c.SO4^2-
Based on factors affecting bond length, the rank from shortest to longest bond length is SO42-, SO32- SO2.
What is bond length?The bond length of a bond is defined as the average distance between nuclei of two bonded atoms in a molecule.
The bond length is determined by the number of bonded electrons also known as bond order.
The higher the number of bonded electrons, the shorter the bond length and vice versa.
SO2 has the least number of bonded electrons, followed by S032- and then SO42-.
Therefore, the rank from shortest to longest bond length is SO42-, SO32- SO2.
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PLEASE HELP I DONT UNDERSTAND AT ALL I’LL GIVE BRAINLEST
1. An experiment calls for 3 moles of FeCl how many grams of Iron (IIl) chloride would you measure out?
2. Copper sulfate is a common compound how many moles are contained in a 3.2 gram sample?
3. How many moles of solid Iron would be contained in a 112gram sample of Iron?
4. If 12 grams of lead is loaded into a shotgun shell, how many atoms of lead are contained in the shell?
5. If a 6 gram sample of Carbon is measured in a lab how many moles of Carbon is there?
6. Convert 120 grams of Calcium to atoms of Calcium,
7. How many atoms of Vanadium are contained within a 2.63 mole sample?
8. What is the molar mass of Mg0?
9.Cows can produce upwards of 250L of methane in a day. On a particular day Bessy the cow produces 11.16
moles of methane (CHa). How many atoms of methane did Bessy add to the atmosphere that particular day?
10. How many moles of KMnO, are contained in a solution of KMnO, that was created using 0.23 grams of KMnO4?
11. How many grams are there in 3.4 × 10^24 molecules of NH3?
12. A lab calls for 2 grams of (NH4)3 PO3, however the sample you have contains 4.3 moles of (NH4)3 PO3, do you have
enough of a sample to complete the lab? How much more is needed/left over?
13. If 9.3x10^-3 moles of ZnO react in a sample how many grams of zinc oxide were originally present?
14. A sample of NaOH is weighed and measured so that it contains exactly 3.41x10^22 molecules, how many grams
were originally weighed out?
15. Carbon monoxide is a colorless odorless gas that in a closed environment is lethal at 2 ppm, which is .002 grams
per liter of air. A liter sample of air contains 1.01x10^18 molecules of CO, how many grams of CO are present in
the sample.
Answer:
the molar mass of mgo is 40.3
If the temperature of the water were 0°C and the pressure was above 760 mm Hg, what phase would the water be in?
-Gas
-Liquid
or
-Solid
(Note pick one answer only)
Answer:
the answer is liquid.
Explanation:
A student who did the same experiment that you did determined the specific heat for all of the metals. His values were all 0. 10 to 0. 20 less than the actual specific heat values. Select all possible sources of this error listed below. The metals were not heated to 100°C. The metals were heated beyond 100°C. The metals cooled before they were added to the water. The thermometer was not completely submerged in the water while reading. The calorimeter was not sealed properly, so heat escaped. Less metal was added to the calorimeter than was massed.
The error source is metals were heated to 100 degrees celsius, they were cooled before water addition, a thermometer was not submerged properly, and the calorimeter was not sealed properly.
What are specific heat and calculation errors?To raise the temperature by one degree of the one gram substance the heat required is called specific heat. The heat given by the system gets absorbed by the surrounding environment.
As the calorimeter was not sealed properly the heat from the system got escaped to the outer environment and the metals of the experiment were not heated till the specific temperature required.
The heat got transferred from the hotter to the cooler environment even before water addition. While taking the readings for the experiment the thermometer was not completely dipped and the values of the specific heat differed.
Therefore, errors during the measuring and estimation vary the calculation.
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What is Molecules ???
.
.
Good evening (๑•ᴗ•๑)♡
A combination of two or more elements or compound combine each other is called as molecules.
.
.
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Gud mrng sis
Look at the map and follow the paths of the Colorado, Gila, and Salt Rivers. Then, answer the following questions
1.What river has the most dams on it?
2.What are the bodies of water behind a dam called?
3.Name three dams on the Colorado River. HELP ME PLS!
which of these is a element
Answer:
its b i remember learning this
Explanation:
5. A car travelled for 6 hours at a distance of 60 kilometers. What is the speed
of the car?
A. 10 km/h
B. 20 km/h
C. 30 km/h
D. 60 km/h
Answer:
A. 10 km/h
its the answer.......................................
Why do we need to use moles when we try to determine amounts of reactants and products in a reaction?.
[tex]\huge\fbox{Answer ☘}[/tex]
Chemists use the mole unit to represent 6.022 × 10 23 things, whether the things are atoms of elements or molecules of compounds. This number, called Avogadro's number, is important because this number of atoms or molecules has the same mass in grams as one atom or molecule has in atomic mass units.
hope helpful~
Define melting, evaporation, freezing, sublimation and condensation.
Answer:
Melting- The process by which a substance changes from its solid state to its liquid state.
evaporation- turning liquid into vapor.
Freezing- The process by which a substance changes from its liquid state into its solid state.
condensation- water which collects as droplets on a cold surface when humid air is in contact with it
sublimation- a solid deposit of a substance which has sublimed.
Explanation:
Which answer is the right one
Answer:
Pressure and volume
How many formula units are in 3.25 moles of (NH4)2SO4
Answer:
Three formula units, Two Ammonium radical and Sulphate radical
Explanation:
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solve this questions please
Answer:
A
Explanation:
A solid that dissolves in water produce alkaline solutions
ex. sodium reacts with water to form sodium hydroxide – caustic soda
What is the percentage of nitrogen, by mass, in calcium nitrate?.
Answer:
Nitrogen = 17.07%
Explanation:
We are asked to calculate the percentage by mass of nitrogen in Ca(NO3)2.
The molar mass of calcium nitrate is 164,088 g/mol.
In this 164.088 g/mol there are 2 nitrogen atoms.
Molar mass of nitrogen = 14,0067 g/mol
% Nitrogen = molar mass of N/total molar mass of the compound
% Nitrogen =[(2 x 14.0067)/164.088]*100
% Nitrogen = 17.07%
Please mark me as brainliest if you found this answer helpful
At what temperature will 0.554 moles of helium gas occupy 11.30 liters at 1.95 atmospheres?
Also, what are the 4 gas laws, and what relationships do the represent?
Answer:
This is what we're given:
P (pressure), which is 1.95 atm
V(volume), which is 11.30 L.
n(number of moles), which is 0.554 moles of helium gas.
We have to find T, or temperature. To do this, we'll need to use the Ideal Gas Law, which is:
[tex]PV = nRT[/tex]
Rearranging this equation to get temperature on one side, we get:\\ [tex]T =\frac{PV}{nR}\\ \\
Pressure \: is \: in \: atm \: and \\ volume \: is \: in \: L . \: This \: tells \\ \: us \: that \: we'll \: need \: to \: \\ use \: the \: value \: of \: 0.08206 L atm/K \: mol \: for \: R \: the \: ideal \: gas \: constant.\\ \\ Plugging in all of the values, we can solve for temperature:
[tex]T =\frac{PV}{nR}\\ \\
T = (1.95 atm × 12.30 L) ÷
(0.654 mol × 0.0820575LatmK−1)
mol
[tex]T =\frac{PV}{nR} \\ \\
T =
\frac{ (1.95 atm × 12.30 L)}{(0.654 mol × 0.0820575LatmK−1)} [/tex]
[tex]T = 447 K [/tex]
4 gas laws, and relationships do they representBoyle’s Law (PV law)
a. Volume of a GIVEN MASS OF GAS (mass is fixed) is inversely proportional to the Absolute pressure of the gas at constant Temperature.
b. Absolute pressure means pressure that is measured relative to Vacuum. Vacuum = 0 pressure. Thus, absolute pressure is measured relative to absolute 0.
c. Another way : PV = Constant. Thus, if you measure the Pressure and Volume at 3 different times, then P1 V1 = P2 V2 = P3 V3. In order to keep the product as a constant, whenever Pressure increases, the Volume will decrease.
Charle’s Law (VT Law)
a. Volume of a GIVEN MASS OF GAS (mass is fixed) is directly proportional to the Absolute Temperature at constant pressure.
b. When you measure the Temperature of a body on a scale in which 0 corresponds to Absolute 0, then the measured temperature is Absolute Temperature. Put simply, this refers to the Kelvin scale.
c. Absolute 0 is the temperature at which objects are at their lowest possible energy (Since Temperature is a measurement of the Kinetic energy of the atoms).
Gay Lussac Law (PT Law)
a. Pressure of a GIVEN AMOUNT OF MASS (mass is fixed) at constant volume is directly proportional to the absolute Temperature (that is, Kelvin Temperature).
b. Another way : P / T = Constant. P1 / T1 = P2 / T2 = P3 / T3.
Avogadro’s law (Vn law)
a. All the above laws were talking about relationships at fixed mass. So we needed a law which would relate mass with other quantities. This is Avogadro’s law.
b. It is a very straight forward law, if the amount of gas in a Container increases (that is, if the amount of matter increases), then the Volume of the gas increases which is very straight forward.
c. Volume is directly proportional to n (number of moles) or V/n = Constant.
Considering the Ideal Gas Law, at 485.05 °K 0.554 moles of helium gas will occupy 11.30 liters at 1.95 atmospheres.
On the other side, the 4 gas laws are Gay Lussac's law, Boyle's law, Charles' Law and Avogadro's law.
Ideal Gas LawIdeal gases are a simplification of real gases that is done to study them more easily. It is considered to be formed by point particles, do not interact with each other and move randomly. It is also considered that the molecules of an ideal gas, in themselves, do not occupy any volume.
The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:
P×V = n×R×T
where:
P is the gas pressure.V is the volume that occupies.T is its temperature.R is the ideal gas constant. The universal constant of ideal gases R has the same value for all gaseous substances. n is the number of moles of the gas.Temperature of heliumIn this case, you know:
P= 1.95 atmV= 11.30 LT= ?R=0.082 [tex]\frac{atm L}{mol K}[/tex]n= 0.554 molesReplacing in the Ideal Gas Law:
1.95 atm×11.30 L = 0.554 moles× 0.082 [tex]\frac{atm L}{mol K}[/tex]× T
Solving:
T= (1.95 atm×11.30 L) ÷ (0.554 moles× 0.082 [tex]\frac{atm L}{mol K}[/tex])
T= 485.05 K
Finally, at 485.05 °K 0.554 moles of helium gas will occupy 11.30 liters at 1.95 atmospheres.
Gay Lussac's lawGay Lussac's law states that the pressure of the gas is directly proportional to its temperature: when there is a constant volume, as the temperature increases, the pressure of the gas increases. And when the temperature is decreased, gas pressure decreases.
Boyle's lawBoyle's law says that volume is inversely proportional to pressure: if pressure increases, volume decreases; while if the pressure decreases, the volume increases.
Charles' LawCharles' Law that the volume is directly proportional to the temperature of the gas: if the temperature increases, the volume of the gas increases; while if the temperature of the gas decreases, the volume decreases.
Avogadro's lawAvogadro's law states that the volume is directly proportional to the amount of gas: if the amount of gas increases, the volume will increase, while if the amount of gas decreases, the volume will decrease.
SummaryIn summary, the 4 gas laws are Gay Lussac's law, Boyle's law, Charles' Law and Avogadro's law.
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4NH_3+ 〖3 O〗_2 → 2 NO+6 H_2 O
1. How many grams of NO can be produced from 12 g of NH3 and 12 g of O2?
2. What is the limiting reactant? What is the excess reactant?
3. How much excess reactant remains when the reaction is over?
[tex]\\ \tt\hookrightarrow 4NH_3+3O_2\longrightarrow 2NO+6H_2O[/tex]
#1
We can solve through ammonia or oxygen .Lets go through ammonia
4mol of ammonia produces 2mol NO2mol of ammonia produces 1mol NO1mol of ammonia produces 0.5mol NO.Moles of Ammonia
[tex]\\ \tt\hookrightarrow \dfrac{12}{17}=0.7mol[/tex]
Moles of NO
[tex]\\ \tt\hookrightarrow 0.7(0.5)=0.35mol[/tex]
Mass of NO
0.35(30)=10.5g#2
NH_3 is excess reagent and O_2 is limiting reagent .
#3
We need ∆n
∆n=8-7=1molSelect the correct answer. Thomas has 235 grams of K2S in the chemistry lab. How many atoms of potassium (K) are in 235 grams of the compound? A. 2. 13 × 1023 B. 4. 26 × 1023 C. 2. 57 × 1024 D. 3. 37 × 1024 E. 7. 08 × 1024.
Atoms are the smallest division of the element. The potassium atoms present in the 235 gm of the compound is [tex]2.57 \times 10^{24}[/tex] atoms.
What is the number of atoms?Given,
Mass (m) of Potassium sulfide [tex](\rm K_{2}S)[/tex] = 235 gmMolar mass (M) of Potassium sulfide = 110.26 g/molCalculate the number of moles as:
[tex]\begin{aligned}\rm Moles (n) &= \dfrac{\rm mass}{\rm molar\;\rm mass}\\\\&= \dfrac{235}{110.26}\\\\&=2.13\;\rm mol\end{aligned}[/tex]
In the given compound [tex]\rm K_{2}S[/tex], there are two atoms of potassium and one atom of sulphur.
If, 1 mole = [tex]2 \times 6.022 \times 10^{23}[/tex] atoms of potassium
Then, 2.13 moles = X atoms
Solving for X:
[tex]2.13 \times 2 \times 6.022 \times 10^{23} = 2.57 \times 10^{24}[/tex]
Therefore, option c. [tex]2.57 \times 10^{24}[/tex] is correct.
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_______ marshes are the most diverse.
Answer:Freshwater marshes are the most diverse
Explanation:
Answer:
freshwater
i got it right on my test
Hope This Helps :D