Answer:
1.5e + 24 I think, hope this can help
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]
The Moon only emits light at night.
True
False - does not emit light at all
Answer:
It's trueeeeeee:))))))
Answer:
TRUE
Explanation:
How are the testes and the ovaries similar?
They are part of the human skeleton.
They are reproductive organs.
They are sensory organs.
They produce sperm.
can alluminium sulphate or carbonate test the purity of water
Explanation:
When added to water, aluminum sulfate causes microscopic impurities to clump together into larger and larger particles. These clumps then settle to the bottom of the container and can be filtered out. This makes the water safer to drink
,
The molarity of a solution that contains 28 g KOH (molar mass 56 g/mol) per 250 mL of solution is:
What is the answer to this?
the answer is A.
the scientist used mud and vinegar to make a model of the volcano.
An organism whose cell contains a nucleus.
Answer:
Eukaryotes
Explanation:
Name the gases that mostly compose the atmosphere.
O Argon and Carbon Dioxide
O Oxygen and Carbon Dioxide
Oxygen and Nitrogen
Carbon Dioxide and Nitrogen
Explanation:
Oxygen and Nitrogen. is the correct pair.
If a sound wave refracts, what happens to it? Select all that apply.
It changes its speed and wavelength when it bounces off of a solid surface.
B
It changes direction when it passes through an opening
С
It changes its speed and wavelength when it passes through an opening
D
It changes direction when it passes from one medium to another
E
It changes its speed and wavelength from one medium to another.
F
It changes direction when it bounces off of a solid surface.
If a sound wave refracts,It changes its speed and wavelength when it bounces off of a solid surface,It changes its speed and wavelength when it passes through an opening, and It changes direction when it passes from one medium to another. Therefore, option A, C and D are correct.
What is refraction of sound wave ?An important case in which sound waves change form or spread out is called refraction. This phenomenon affects the bending of a sound wave owing to changes in the wave's speed.
Refraction is the reason ocean waves near a shore parallel to the beach and why glass lenses can be used to focus light waves.
If the air above the earth is warmed than that at the surface, sound will be change shape back downward toward the surface by refraction. Sound propagates in all directions from a point source.
Thus, option A, C and D are correct.
To learn more about the refraction of sound wave, follow the link;
https://brainly.com/question/17227614
#SPJ6
I’ll give the brainliest
What will happen to buildings, statues and canyons where water flows through them over many years?
Answer:
Water gradually degrades them until the metal parts rust and the other materials deteriorate.
Explanation:
What variables are used to calculate speed
S /\ Speed
mph, km/h, ft/s
Answer:
Calculating speed, distance and time
We can use formulas to model real-life situations. For example, the formula for calculating speed is speed = distance ÷ time. It is possible to calculate the speed, distance or time if you have the other two values.
Explanation:
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
Lab: Limiting Reactant and Percent Yield
Student Guide
Pre-Lab Information
Purpose Explore the yield of a chemical reaction by identifying the limiting reactant, comparing the
theoretical and actual yields, and explaining the sources of error.
Time Approximately 45 minutes
Question While observing a chemical reaction, how can you tell which reactant is limiting?
Reaction The reaction of copper(II) chloride and aluminum is shown in this balanced equation:
3CuCl2 + 2Al 2AlCl3 + 3Cu
Hypothesis If a substance is the limiting reactant, then it will be fully consumed by the time the
reaction completes because it is the reactant that reacts completely and the reaction
cannot proceed further.
Summary You will react copper(II) chloride with different quantities of aluminum in two trials. You
will also calculate percent yield for Trial 2.
Answer:
pre lab information would be the thing you to ressearch the lab to get the information
Limiting Reactant and Percent Yield Lab Report attached
what is the electronic structure of an atom with a proton number 11 and mass number 23
Answer:
1s^2 2s^2 2p^6 3s^1
Explanation:
electron configuration of an element gives description of the distribution of electron in it's orbital of the atom, the superscript symbolize number of electron been hold by them.
The element here is sodium, which is a alkali metal
mass number =23
Number of proton= 11
electron must be seen in thelowest-energy subshell that is available in the the 3s orbital,
Hence, the electronic configuration is
1s^2 2s^2 2p^6 3s^1
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
What can lead to being curious and also lead to fascinating scientific investigations? a. Questions b. Answers c. Qualitative Measurements d. Quantitative Measurements
Answer:
Questions
Explanation:
The word "science" was obtained from the Latin word "Scire" which means "to know". Hence science is a systematic investigation into the nature of the universe.
Scientific investigations begin with asking questions about the universe. It is this curiosity to know about occurrences in the universe as well as how to solve problems in the universe that leads to fascinating scientific investigations and discoveries.
At what temperature would the volume of a gas be 0.550 L if it had a volume of 0.432 L at –20.0°C? Be careful! This is not in the correct units for temperature.
Answer:
49.2°C is the temperature
Explanation:
Based on Charles's law, the absolute temperature of a gas is directly proportional to the volume under constant pressure. The equation is:
V1 / T1 = V2 / T2
Where V is volume and T is absolute temperature of 1, initial state and 2, final state of the gas.
Computing the values of the problem:
V1 = 0.432L
T1 = -20.0°C + 273.15K = 253.15K
V2 = 0.550L
T2 = ?
0.432L / 253.15K = 0.550L / T2
322.3K = T2
322.3K - 273.15 =
49.2°C is the temperatureWhat is the average speed of a race car if it travelled a total of 500 miles in 3.5 hours
Answer:
speed = 142.8571 miles per hour OR 142.8571 mi/h
Explanation:
speed= [tex]\frac{distance}{time}[/tex]
distance = 500, time = 3.5hours or 210 minutes
speed= [tex]\frac{500}{210}[/tex] = 142.8571
hope this helps!!!!
Earth is currently 150 million km away from the Sun. If Earth was 200 million km away from the Sun, why would it no longer be able to support life?
Answer:
The temperature would be too cold
Explanation:
can someone pleaze help me
Answer:
I think its the last one
Explanation:
Super sorry if its incorrect.
How many mL of a 1.63 M solution would contain 12 g of Na(OH)?
Answer:
89 mL of solution would contain the given amount of Al(NO₃)₃.
Explanation:
Hope this help
How many moles of nitrogen gas are present in a 28.9 dm3 temperature of 55.0 °C and a pressure of 144 kPa?
Given :
Temperature, T = 55° C = ( 55 + 273 ) K = 328 K .
Volume of container, V = 28.9 dm³ = 0.0289 m³ .
Pressure, P = 144 kPa = 144000 Pa .
To Find :
Number of moles of nitrogen gas.
Solution :
We know, by ideal gas equation :
PV = nRT ( R ( universal gas constant ) = 8.31 J K⁻¹ mol⁻¹ .
[tex]n = \dfrac{PV}{RT}\\\\n = \dfrac{144000\times 0.0289}{8.31 \times 328} \ moles\\\\n = \dfrac{4161.6}{2725.68}\\\\n = 1.53 \ moles[/tex]
Therefore, number of moles of nitrogen gas is 1.53 moles.
A material in which electrons are able to move easily or freely is a(n)
A none of these
В electric field
C insulator
D conductor
Answer:b
Explanation:
Sn(IV) and Br
chemical formula
A sealed container is heated from 110K to 175K. The gas begins at a volume of 95L, what is the new volume of the gas upon heating?
PLEASE HELP ME ASAP!!!!!!!!!!!!!
6) A student measures out 96.21 g of sulfur for an experiment. How many moles of Sulfur are in this
sample? (show your work!)
Atomic mass of Sulfur = 32g
32g of Sulfur is one mole.
1g of Sulfur is [tex] \frac{1}{32} moles [/tex]
96.21g of Sulfur is [tex] \frac{96.21}{32} moles=> 3moles(appx) [/tex]
Answer:
[tex]\boxed {\boxed {\sf 3 \ moles \ sulfur}}[/tex]
Explanation:
To convert from grams to moles, the molar mass is used. This value is the number of grams in 1 mole of a substance and it can be found on the Periodic Table. Look for Sulfur or S.
Sulfur: 32.07 g/molWe use this as a ratio.
[tex]\frac {32.07 \ g \ S}{1 \ mo;\l\ S }[/tex]
Multiply by the given number of grams.
[tex]96.21 \ g \ S*\frac {32.07 \ g \ S}{1 \ mo\l\ S }[/tex]
Flip the fraction so the grams of sulfur cancel out.
[tex]96.21 \ g \ S*\frac {1 \ mol \ S}{32.07 \ g \ S }[/tex]
[tex]96.21*\frac {1 \ mol \ S}{32.07 }[/tex]
[tex]\frac {96.21 \ mol \ S}{32.07 }= 3 \ mol \ S[/tex]
96.21 grams of sulfur is equal to 3 moles of sulfur.
What is the poh of a solution with a ph of 1.30? PLZZ ANSWER
Answer:
12.70
Explanation:
Balance the following chemical equation:
C2H60+02 → CO2 + H20
Answer:
Explain: In order to balance the chemical equation, you need to make sure the number of atoms of each element on the reactant side is equal to the number of atoms of each element on the product side. In order make both sides equal, you will need to multiply the number of atoms in each element until both sides are equal.
Lyle filled a glass bottle completely with water. He put the lid on tightly, then put the water in the freezer to cool it down quickly. Lyle forgot about his water until the next day. When Lyle took his bottle out of the freezer, all the water was frozen solid. The bottle had cracked in several places and was broken. If water in the ground acts like water in the bottle when it freezes, how does water in the ground affect layers of rock and soil
Answer:
The answer would be It breaks them up.
Explanation: