Answer:
8.43 x 1024 moles of I
Explanation:
Certain minerals exclude lead but not uranium from their crystal structure, so when the minerals form they have no lead, only uranium. As time goes on, the uranium decays to lead, so measuring the ratio of lead atoms to uranium atoms allows investigators to determine the ages of the minerals. If a sample of a mineral contains 3 atoms of 207Pb207Pb for every 1 atom of 235U235U, how many years ago was it formed
Answer:
The answer is "[tex]1.4 \ \bold{ billion-years}[/tex]".
Explanation:
Using formula:
[tex]\to N_{Now} = N_{orige}e^{\lambda t} \\\\[/tex]
[tex]\to[/tex] 1 U atom produces 1 Pb atom after decay.
[tex]\to[/tex] U's original numbers are now the sum of U counts and Pb counts.
[tex]\to N_U=(N_U+N_{pb})e^{\lambda Ut}[/tex]
[tex]\to 1 = (1+3) \ exp[(\frac{-\ln(2)}{t_{(half)}} \times t ]\\\\\to t = [\frac{\ln(4)}{\ln(2)}] \times t_{(half)}[/tex]
[tex]= 14 \times 10^8 \ \ years\\\\=1.4 \ billion \ \ years[/tex]
What is the mass in grams of 9.02x10^28 atoms of Fe
Answer:
83.674 grams of Fe
Explanation:
9.02 x 10²⁸ atoms
To convert from atoms to grams, we first need to convert atoms to moles. To do this, divide the atoms by Avogadro's Number, 6.02 x 10²³
9.02 x 10²⁸ ÷ 6.02 x 10²³
= 1.498 moles of Fe
Now we need to convert moles to grams. To do this, multiply the moles by the molar mass of Fe. The molar mass can be found on the periodic table.
1.498 • 55.845
= 83.674 grams of Fe
Hope this helps!
Which of the elements shown will form ions, what will be the charges of those ions, and why will they have those charges?
Answer:
the sodium and chlorine are the form of ion
Explanation:
because sodium have tendency to loose electron it become positive ion and chlorine has tendency to gain electron it becomes negative ion
7.(05.02 MC)
The speed of light in four different materials is shown below:
Material Speed of light in thousand miles per second
A
140
B
78
С
186
D
12
Which material is the most dense? (4 points)
Material A
Material B
Material C
Material D
Answer:
C
Explanation:
thats the answer!! HEHEHHEHHHHSJSKSSSSJS
Answer: B or A
Explanation: Everyone is saying C and i just took the test and it is not C
Please help me it's urgent!!!!!
What does the reaction rate measure?
O A. The collisions per second
O B. The speed of the reaction
C. The reaction activation energy
O D. The moles per liter of product
Answer:
The speed of the reaction
Explanation:
I just took the test and got it right... i hope this helps u :)
Round the following number to 3 significant figures:
15937
pls helpppp
Answer:
15900
Explanation:
I think hope this helps!! :D
Answer:
15900
Explanation:
What is the density of an object that has a mass of 10 grams and a volume of 5 mL?
Answer:
2 g/mLExplanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\[/tex]
From the question we have
[tex]density = \frac{10}{5} = 2 \\ [/tex]
We have the final answer as
2 g/mLHope this helps you
please help
whats the skeleton equation
for this equation
copper sulfate + sodium hydroxide --> copper hydroxide
Answer:
Copper(II) sulphate – sodium hydroxide reaction
The reaction between copper(Il) sulphate and sodium hydroxide solutions is a good place to start. If you slowly add one to the other while stirring, you will get a precipitate of copper(II) hydroxide, Cu(OH)2.
A student performs an acid-base titration experiment to determine the amount of ascorbic acid in different brands of juice. Which solution should the student use as the base solution in this acid-base titration experiment?
A.) HCl
B.) NaOH
C.) LiBr
D.)CaCl2
Answer:
idn Mann nnnnnnnn . .....mmmmm mmmm aaaaaaa it's a
The answer is Option B, NaOH is the solution student should use as the base solution in this acid-base titration experiment to determine the amount of ascorbic acid in different brands of juice.
What is an Acid Base Titration ?
An acid–base titration is a method of quantitative analysis.
It is used for determining the concentration of an acid or base by neutralizing it with a standard solution of base or acid of known concentration.
An indicator is used to monitor the progress of the acid–base reaction.
Ascorbic acid, HC₆H₇O₆ is an acid. So can be titrated with a base , sodium hydroxide, NaOH using the indicator, phenolphthalein.
HC₆H₇O₆(aq) + NaOH(aq) → NaHC₆H₇O₆(aq) + H₂O(l)
Among the options , HCl is an acid , LiBr , CaCl₂ are salts , NaOH is the only base.
Phenolphthalein changes from colorless to pink (or red) when all of the acid gets neutralized.
Therefore NaOH is the solution student should use as the base solution in this acid-base titration experiment to determine the amount of ascorbic acid in different brands of juice.
To know more about Acid Base Titration
https://brainly.com/question/15220646
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how does a drought (lack of water) affect an ecosystem?
When a drought occurs, their food supply can shrink and their habitat can be damaged. Lack of food and drinking water for wild animals. Increase in disease in wild animals, because of reduced food and water supplies. Migration of wildlife.
What happens to sediments that get deposited in basins?
Sedimentary basins are regions of the Earth where long-term subsidence creates accommodation space for accumulation of sediments. As the sediments are buried, they are subject to increasing pressure and begin the processes of compaction and lithification that transform them into sedimentary rock.
Answer: Sedimentary basins are regions of the Earth where long-term subsidence creates accommodation space for accumulation of sediments. As the sediments are buried,
Explanation:Hopeits right i fount it on a site
What type of circuit has a broken path that does NOT let current flow through it?
A : Closed circuit
B: Open circut
C : Toggle
D : Switch
Answer:
B
Explanation:
How much heat is required to raise the temperature of 18 grams of liquid water by 25 C?
Since the molecular weight of water is about 18 g/mol, you have about 1 mol of water. So, now we know that it takes approximately 46.2 kJ of heat energy to warm 18.02g of water from 25C to 100C and then to vaporize it into steam. Hopefully this helped!
Explanation:
Question 4
1 pts
24) Which statement best describes what happens to the particles in ice as it melts?
A) They lock into place.
B) They move more rapidly.
C) They lose some of their mars.
D) They become electrically charged.
How do you know if a material is an elernent or a compound?
Explanation:
Elements and compounds are both examples of pure substances. A substance that cannot be broken down into chemically simpler components is an element. ... A substance that can be broken down into chemically simpler components (because it has more than oneelement) is a compound.
2 uniones iónicas y 2 covalentes, realizando las estructuras de Lewis correspondiente y averiguar la función del compuesto armado en la vida cotidiana.
Answer:
Cloruro de sodio y fluoruro de sodio.
Dióxido de carbono y monóxido de hidrógeno.
Explicación:
El cloruro de sodio y el fluoruro de sodio son los compuestos que tienen enlaces iónicos. Estos compuestos iónicos se utilizan para diferentes actividades de nuestra vida diaria. El cloruro de sodio se usa para cocinar y el fluoruro de sodio se usa en la pasta de dientes para limpiar nuestros dientes. El dióxido de carbono y el monóxido de hidrógeno son compuestos que tienen enlaces covalentes. El dióxido de carbono se usa en refrescos / refrescos y algunos otros líquidos que se pueden usar en la vida diaria. El monóxido de hidrógeno es el agua pura que bebemos todos los días en nuestra vida diaria y es muy importante para nuestra supervivencia.
it is used to lift water from a well
Answer:
When air is admitted into the well, the water recedes from the level of static head to the bottom of the discharge pipe. The displaced column of liquid rises up the discharge pipe. Air bubbles mix with water and this reduces the specific gravity of the column of water sufficiently to lift it to the surface.
Explanation:
Why do silver and copper have similar properties?
(7th Grade science)
Answer:
They are both listed under group 11 on the periodic table and both are highly conductive of electricity
Explanation:
HOPE THIS HELPS ^^
Why does photosynthesis require 6 molecules of carbon dioxide and 6 molecules of water to make 1 molecule of glucose
For each molecule of glucose produced: 6 water water molecules are oxidized, and come to be the supply of electrons for carbon dioxide reduction. 6 molecules of carbon dioxide are required, one for every carbon atom in glucose. 6 molecules of oxygen are produced as a with the aid of made from water oxidation.
The Universal Space Agency wants to know the results of your Sim investigation. Write your report to the lead chemist, explaining why there is liquid water on the outside of the can but no liquid nitrogen. Use evidence from your investigation in your explanation.
Answer:
Due to warm temperature.
Explanation:
There is water present in liquid form instead of liquid nitrogen on the outer side of the can because of the temperature present in the surrounding environment. The temperature around the can is little warm which is favourable for the water but not for the liquid nitrogen. The liquid nitrogen present in liquid state when the temperature of the surrounding is too cold. if it is warm, the liquid nitrogen starts boiling and converts into gaseous state so that's why the warmer temperature is responsible for the presence of water not the liquid nitrogen.
What is the formation of gas is an example of?
Answer:
The formation of a gas is a clue to chemical changes. The bubbles of gas that you observed form when an antacid is dropped into water is an example of change. ... As wood burns, it turns into a pile of ashes and gases that rise into air.
Explanation:
An organism that can make its own food may be classified into one of several kingdoms, depending on other characteristics. Based on this information, in which of the following kingdoms would this organism NOT be classified?
Archaea
Fungi
Plant
Protista
Help me!!!!!
The would not be classified into archaea.
So, A.
what do a bald eagle, a komodo dragon, and a lizard have in common
Answer:
All of them derive from a common ancestor. They each share something in their DNA that ties into their past selves, which were more closely related. As they evolved, they became more and more distant, but we can still trace them back to the olden days.
Also they all have scales.
Hope this was at least semi-useful.
Please help me on this
Answer:
the answer is 3(decay) and
the second isa 1(alfa particle) has a mass of equal to helium nucleus
The "fuel" in most combustion reactions
is a hydrocarbon. Using the examples in
Model 2, write a description for the
classification of substances known as
hydrocarbons.
Answer:
hydracarbons are substances consisting of carbon and hydrogen only
Explanation:
how many moles of ammonia could be obtained from a maximum of 5.0 moles of nitrogen
Answer:
10 moles of ammonia could be obtained from a maximum of 5.0 moles of nitrogen.
Explanation:
The balanced reaction is:
N₂ + 3 H₂ → 2 NH₃
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:
N₂: 1 moleH₂: 3 molesNH₃: 2 molesThen you can apply the following rule of three: if by reaction stoichiometry 1 mole of nitrogen produces 2 moles of ammonia, 5 moles of nitrogen produces how many moles of ammonia?
[tex]moles of ammonia=\frac{5 moles of nitrogen*2 moles of ammonia}{1 mole of nitrogen}[/tex]
moles of ammonia= 10
10 moles of ammonia could be obtained from a maximum of 5.0 moles of nitrogen.
PLEASE Answer asap! What characteristics are shared by all alkali metals and alkaline earth metals?
A. They conduct electricity very well
B. They are strong and shiny
C. They form alkaline solutions when mixed with water
D. They do not react with water at all
Answer:
C
Explanation:
Mostly all of them but most likely C
A gas has a volume of 5.00 L at 20 degrees Celsius. What is the volume of gas at 150 degrees Celsius.
Answer:
7.22 L
Explanation:
From the question,
Applying Charles law,
V₁/T₁ = V₂/T₂...................... Equation 1
Where V₁ = Initial volume of gas, V₂ = Final volume of gas, T₁ = Initial Temperature of gas in Kelvin, T₂ = Final Temperature of gas in Kelvin
Make V₂ the subject of the equation
V₂ = (V₁×T₂)/T₁................. Equation 2
Given: V₁ = 5.00 L, T₁ = 20 °C = (20+273) K = 293 K, T₂ = 150 °C = (150+273) K = 423 K
Substitute these value into equation 2
V₂ = (5.00×423)/293
V₂ = 7.22 L
How many atoms of hydrogen are there in one molecule of water. if the chemical formula is H202 ?
a. 0
b. 1
c. 2
d. 3