Answer:B
15 carbon atoms
Which nuclear equation represents a spontaneous decay?
Answer:A
Explanation:
1. [tex]^{222}Rn_{86}[/tex] → [tex]^{218}Po_{84} + ^{4}He_{2}[/tex]
What is a spontaneous decay?
Spontaneous fission (SF) is a form of radioactive decay where an atom's nucleus splits into two smaller nuclei and generally one or more neutrons.Out of the given options, only option 1. [tex]^{222}Rn_{86}[/tex] → [tex]^{218}Po_{84} + ^{4}He_{2}[/tex] is an example of spontaneous decay since an atom nucleus is splitting into two daughter nuclei's.Spontaneous decay would refer to whether or not decay was stimulated by bombardment with neutrons or alphas while random decay refers to the selection of which nuclei actually decayLearn more:
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Give two examples of each of the following:
1.) Physical systems designed by people.
2.) Naturally occurring physical systems.
3.) Social systems that you are a part of.
4.) Naturally occurring social system.
El osmio es un metal sólido que tiene una densidad
de 22 600 kg/m?, ¿qué volumen ocuparán 100 g de
este metal?
Answer:
4.42x10⁻⁶ m³
Explanation:
Primero convertimos 100 gramos a kilogramos:
100 g / 1000 = 0.100 kgAhora se puede calcular el volumen que ocuparán 0.100 kg de osmio, usando la densidad dada por el problema:
Densidad = masa / Volumen22600 kg/m³ = 0.100 kg / volumenvolumen = 4.42x10⁻⁶ m³La respuesta es 4.42x10⁻⁶ m³.
1. Phosphorous reacts with bromine to form phosphorous tribromide. If 35.0 grams of bromine
reacted and 27.9 grams of phosphorous tribromide are actually formed.
what is the percent yield of phosphorous tribromide (PBr3)?
2 P + 3 Br2 ---> 2 PBr3
(Note that the molar masses: P=30.97g, Br = 79.90g) Show your steps
*
Please help me
Answer:
70.6 %
Explanation:
First step, we define the reaction:
2P + 3Br₂ → 2PBr₃
We determine the moles of reactant:
35 g . 1mol / 159.8 g = 0.219 moles
We assume, the P is in excess, so the bromine is the limiting reagent.
3 moles of Br₂ can produce 2 moles of phophorous tribromide
Then, 0.219 moles may produce (0.219 . 2) /3 = 0.146 moles of PBr₃
We convert moles to mass:
0.146 mol . 270.67 g /mol = 39.5 g
That's the 100 % yield reaction, also called theoretical yield. The way to determine the % yield is:
(Yield produced / Thoeretical yield) . 100
(27.9 / 39.5) . 100 = 70.6 %
best way to hump girls
Answer:
When they're sleeping
Explanation:
After they've been drugged
the means of X ? ⊙_⊙⊙_⊙⊙_⊙
Answer:
x means unknown it is an unknown value.
For example if you have 2 x you have 2 u know values.
Explanation:
If you want us to explain it further please provide a picture.
What is X
Answer:-X mean an Unknown value in a question.
for example :- 2x = 4
→ Here, the value of x is not known but it can be known by solving the problem.
The solution is :-
=> 2x = 4
=> x = 4/2
=> x = 2
So, here the value of X is 2
Hence, we can say that "X is an unknown value in a question and solving that question gives the correct value of x"
-TheExtraterrestrial
Which is the same as moving the decimal point 3 places to the left in a decimal
number?
Multiplying the number by 100
Dividing the number by 1,000
Multiplying the number by 1,000
Dividing the number by 100
Answer:
B. Dividing the number by 1,000
Explanation:
Every time you move the decimal ,add a zero.Since the decimal is moved three times ,there are three zeroes. When you move left ,the number is getting smaller so it is division.
1. What is the relationship between pressure and volume?
Answer:
An increase in pressure would cause less volume and vice versa. They are inversely proportional.
Explanation:
This is due to Boyle's Law (and because an increase in pressure would increase the force on the container, however, if it's a closed container, it would burst)
Feel free to mark it as brainliest :D
Which is the best definition of a CHARACTERISTC physical property?
Which compounds are most likely ionic? compounds A and B O compounds B and C compounds C and D O compounds D and A
Answer:
compounds D and A
Explanation:
The ionic compound can conduct electricity therefore, the compounds A and D are most likely ionic. Therefore, option (4) is correct.
What are ionic compounds?Ionic compounds can be defined as crystalline solids produced by closely packed ions with opposite charges. The formation of an Ionic compound takes place when metal reacts with non-metal.
In ionic compounds, the ions of the compound are generally linked together by ionic bonds. The ions of an atom are formed by gaining or losing electrons in order to get the noble gas electronic configuration.
In a reaction, the metals are generally electropositive so they can lose electrons to complete their octet while non-metals will gain electrons from the metals to complete their octet.
Ionic compounds can conduct electricity in a molten state and aqueous solution because then they have free ions that can move from one place to another to conduct an electric current.
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does iodine occur naturally in salt ? yes or no
Answer:
[tex]yes[/tex]
Explanation:
Iodine is present in salt which makes it salty:)
Look at the reaction below. Upper H subscript 2 upper S upper O subscript 4 (a q) plus upper C a (upper O upper H) subscript 2 (a q) right arrow upper C a upper S upper O subscript 4 (a q) plus 2 upper H subscript 2 upper O (l). Which substance is the base in the reaction? A. 2H2O (l) B. H2SO4 (aq) C. CaSO4 (aq) D. Ca(OH)2 (aq)
Answer:
Its D
Explanation:
Did it on edge
According to the reaction: H₂S0₄ + Ca(OH)₂ → CaSO₄+ 2H₂O, the base is Ca(OH)₂.
What is a base?Base is defined as a substance which can accept protons or any chemical compound that yields hydroxide ions (OH-) in solution.
Generally, base are substances that produces hydroxide ion when dissolve in water.
Base are substances that reacts with acid to produce salt and water. Example of base includes sodium hydroxide, potassium hydroxide, magnesium hydroxide, calcium hydroxide etc.
Therefore, according to the reaction:
H₂S0₄ + Ca(OH)₂ → CaSO₄+ 2H₂O
The base is Ca(OH)₂.
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Brainiest and 10 points
Which has a HIGHER frequency?
A. Orange light
B. Blue light
Answer:
A. Orange light
Explanation:
According to the band spectrum of white light ( ROYGBIV )
Answer:
I think it blue light is higher
If 1.00 mol of an ideal monatomic gas initially at 74 K absorbs 100 J of thermal energy, what is the final temperature
Answer:
T = 82 K
Explanation:
The computation of the final temperature is shown below;
Given that
T_0 denotes the initial temperature of the gas i.e. 74 K
T denotes the final temperature of the gas = ?
n denotes number of moles of monoatomic gas i.e. 1.00 mol
R denotes universal gas constant = 8.314
c denotes the heat capacity at constant volume i.e.
= (1.5) R = (1.5) (8.314)
= 12.5
Q denotes the Amount of heat absorbed i.e 100 J
We know that
Amount of heat absorbed is provided as
Q = n c (T - T_0)
100 = (1) (12.5) (T - 74)
T = 82 K
5. Calculate the number of molecules of carbon tetrachloride in 0.32 mol of
carbon tetrachloride.
To Find :
The number of molecules of carbon tetrachloride in 0.32 mol of
carbon tetrachloride.
Solution :
We know, 1 mole of any element/compound contains [tex]6.022 \times 10^{23}[/tex] number of atoms/molecules.
So, Number of molecules in 0.32 mol are :
[tex]n = 0.32 \times 6.022 \times 10^{23}\\\\n = 1.93 \times 10^{23}[/tex]
Therefore, number of molecules of carbon tetrachloride in 0.32 mol of
carbon tetrachloride are [tex]1.93 \times 10^{23}[/tex].
Bromine is a red-brown liquid with a density of 3.10 g/mL. A sample of bromine weighing 88.5 g occupies what volume
Answer:
28.55 mL or 0.02855 L
Explanation:
Applying,
Density(D) = mass(m)/Volume(V)
D = m/V............... Equation 1
Where D = Density of the Bromine, m = mass of the bromine, V = volume of the bromine
make V the subeject of the equation
V = m/D............. Equation 2
From the question,
Given: m = 88.5 g, D = 3.10 g/mL
Substitute these values into equation 2
V = 88.5/3.10
V = 28.55 mL
Hence the volume occuppied by the Bromine gas is 28.55 mL or 0.02855 L
HELP ME OMG
A sample of xenon gas collected at a pressure of 1.15 atm and a temperature of 279 K is found to
occupy a volume of 786 milliliters. How many moles of Xe gas are in the sample?
mol
n = 0.0395 mol Xe
Explanation:
Use the ideal gas law:
PV = nRT
n = PV/RT
= (1.15 atm)(0.786 L)/(0.08205 L-atm/mol-K)(279K)
= 0.0395 mol Xe
A 136 g sample of an unknown substance was heated from 20.0 °C to 40.0 °C. In the process the substance absorbed 2440 J of energy. What is the specific heat of the substance? Identify the substance among those listed in Table 2.
A. the specific heat is 0.897 J/g.C, The Substance is aluminum
B. the specific heat is -0.897 J/g.C, The Substance is aluminum
C. the specific heat is 4.184 J/g.C, The Substance is water
D. there's not enough information to determine which is the substance.
Answer:
Option A. The specific heat is 0.897 J/gºC, The Substance is aluminum.
Explanation:
We'll begin by calculating the change in temperature of the substance. This can be obtained as follow:
Initial temperature (T₁) = 20.0 °C
Final temperature (T₂) = 40.0 °C
Change in temperature (ΔT) =?
ΔT = T₂ – T₁
ΔT = 40 – 20
ΔT = 20 °C
Finally, we shall determine the specific heat capacity of the substance. This can be obtained as follow:
Mass (M) = 136 g
Change in temperature (ΔT) = 20 °C
Heat (Q) absorbed = 2440 J
Specific heat capacity (C) =?
Q = MCΔT
2440 = 136 × C × 20
2440 = 2720 × C
Divide both side by 2720
C = 2440 / 2720
C = 0.897 J/gºC
Comparing the specific heat capacity (i.e 0.897 J/gºC) of the substance with those in the table above, the substance is Aluminum.
Thus, option A gives the correct answer to the question.
Please someone help me!
I need this done ASAP *URGENT*
I Need this done before Thursday or Friday because Friday is my last day of school so please finish this today!
Best answer gets BRAINLIEST
PLEASE HURRY AND ANSWER ALL QUESTIONS CORRECTLY
NO LINKS OR ANSWER REPORTED
What’s the difference worksheet
Atoms,molecules,elements and compounds
PLEASE PLEASE PLEASE PLEASE PLEASEEEEEEE ANSWER THIS I only have TWO days of school left! And I need this done quickly
To solve this we must be knowing each and every concept related to chemical formula. Therefore, in the above given ways the chemical formula for the molecule can be written.
What is chemical formula?A chemical formula is a scientific notation that uses atomic symbol and numerical subscripts to represent the number and types of elements contained in a molecule. A chemical formula seems to be a concise written description of an existing three-dimensional molecule.
A chemical formula characterizes a material to the atomic level. There are three sorts of chemical formulas: empirical, molecular, and structural.
The chemical formula for the given molecules are:
2. H[tex]_2[/tex]O
3. O[tex]_3[/tex]
4. H[tex]_2[/tex]
5. CO[tex]_2[/tex]
6. CO
7. NO[tex]_2[/tex]
8. CH[tex]_4[/tex]
Therefore, in the above given ways the chemical formula for the molecule can be written.
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In which substance are molecules moving the fastest? The options are, a. Solid water (ice) b. Liquid water c. Water vapor (gas)
Answer:
The answer is C
Explanation:
The more space the molecules have the faster they will move, solid doesn't allow movement at all, when it gets to liquid they are free to move around because it's more space, when a gas they can move all around in the air.
What mass of HF is produced according to the given equation when 2.397 grams of each reactants are combined?
CaF2 + H2SO4 --> CaSO4 + 2HF
+HF is the answer
Explanation:
7. water, when heated, changes into this
Answer:
We learned that waterhas three states: ice is the solid state, watervapor is the gaseous state, and wateris the liquid state. When water is heatedit evaporates, which means it turns into watervapor and expands. Secondly, does water expand when heated?
Explanation:
How many moles of SO2 will be produced from 11.5 moles of O2?
Explanation:
Respuesta: La masa atómica del carbono (C) es 12 g/mol; para el oxígeno (O) es de 16 g/mol. Esto significa que 6.022 x 1023 átomos de carbono pesan 12 gramos. Según esto, el peso molecular del CO2 es: 12 g/mol [C] + 2 x 16 g/mol [O2] = 44 g/mol
PLEASE HELP ME!!!!
TRUE or FALSE: When sperm and egg cells combine in fertilization, the
offspring ends up with the same number of chromosomes as their
parents.
Answer: False
Explanation:
Hope this help
Answer:
True.
Explanation:
Every child will contain the same number of chromosomes as the parents (otherwise they wouldn't be considered the same species). Additionally, animals can only mate with a species containing the same number of chromosomes as themselves. This means if the offspring of the parents had a different number fo chromosomes the offspring would be unable to mate with animals of it's own species.
A mixture contains 5.0 g of He, 1.0 g of Ar, and 3.5 g of Ne. Calculate the partial pressure of each gas in the mixture at STP and total pressure of mixture.
Answer:
Total pressure of the mixture = 1 atm
Partial pressure of He = 0.863 atm
Partial pressure of Ar = 0.0173 atm
Partial pressure of Ne = 0.1197 atm
We confirm that the sum of partial pressure of each gas valu
Explanation:
STP conditions are:
1 atm of pressure and
273K of T°
We can also say that those value reffers to 1 mol.
We determine the moles of each:
5 g . 1mol / 4g = 1.25 moles of He
1g . 1mol / 39.9 g = 0.0250 moles of Ar
3.5g . 1mol / 20.18 g = 0.173 moles of Ne
Total pressure of a mixture can be obtained from the Ideal Gases Law.
P . V = n . R . T
Total moles: 1.25 + 0.025 + 0.173 = 1.448 moles
But now, we need the volume. We know that 1 mol is contained at 22.4L at STP.
1.448 mol . 22.4L / 1 mol = 32.4 L
That's the volume for our mixture. We replace:
32.4 L . P = 1.448 mol . 0.082 . 273K
P = (1.448 mol . 0.082 . 273K) / 32.4L = 1 atm
Now we can obtained the partial pressure of each gas from mole fraction
Mol of gas / Total pressure = Partial pressure of gas / Total pressure
Partial pressure of He = (1.25 / 1.448) . 1 atm = 0.863 atm
Partial pressure of Ar = (0.025 / 1.448) . 1 atm = 0.0173 atm
We know that sum of partial pressure is 1 - (Mole fraction He + Mole fr. Ar)
Partial pressure of Ne = 1 - (0.863 + 0.0173) = 0.1197 atm
We confirm that the sum of partial pressure of each gas values the total pressure of the mixture: 0.863 + 0.0173 + 0.1197 = 1
Based on this chart, which of the following statements describes sources of
energy in the United States?
Sources of Energy
Petroleum
3796
Other
91%
Natural Gas
24%
Renewable
Energy
7%
Coal
2396
*Nuclear
Electric Power
8%
A. Most energy comes from nuclear power and renewable sources.
B. Most energy comes from nonrenewable energy sources.
C. Most energy comes from sources in the solid phase.
D. Most energy comes from greenhouse gases.
Answer:
B. Most energy comes from non-renewable sources
Explanation:
A P E X
In United States Most energy comes from non-renewable energy sources, as petroleum coal and others has the highest consumption in the given chart
What is the energy source in US?In the given chart, the energy consumption in US is based on Petroleum, coal and others the highest consumption pattern as compared to other energy sources
Hence, most energy in the US is from non-renewable energy sources
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An archaeologist finds 14C in a sample of material to be decaying at 20 Geiger Counter clicks per second. A modern equivalent sample of the same material decays at 160 clicks per second. The half-life of 14C is 5,730 years. How old is the sample
Answer:
17188 years
Explanation:
Recall the formula;
0.693/t1/2 = 2.303/t log(No/N)
t1/2 = half life of 14C
No = initial activity of 14C
N = activity of 14C at time t
t = age of the sample
Substituting values
0.693/5730= 2.303/t log(160/ 20)
1.21 * 10^-4= 2.0798/t
t = 2.0798/1.21 * 10^-4
t = 17188 years
Radium has a half-life of 1500 years. How long will it take for 250kg of Radium to decay down to less than 10kg
Answer:
6967 years
Explanation:
The radioactive substance left after a periodical t year can be expressed by using the formula:
[tex]Q(t) = Q_oe^{-kt}[/tex]
here;
[tex]Q_o[/tex] = the radioactive initial value.
We need to understand that provided that the radioactive substance will get reduced to half of the provided initial amount after a periodic time, Then:
the half-life of the radioactive substance left is:
[tex]Q(h) = \dfrac{Q_o}{2}[/tex]
Given that:
the half-life = 1500 years
[tex]\dfrac{Q_o}{2}= Q_o e^{-k\times 1500} \\ \\ \dfrac{Q_o}{2}= Q_o e^{ -1500k}[/tex]
Divide both sides by [tex]Q_o[/tex]
[tex]\dfrac{1}{2} =e^{-1500k}[/tex]
Then, find the natural logarithm of both side;
[tex]\mathtt{In \dfrac{1}{2} = -1500 k}[/tex]
[tex]k = \dfrac{1}{-1500}\mathtt{In}\dfrac{1}{2}[/tex]
k = 0.000462
So, after a particular (t) time, a 250 kg radium sample was reduced to 10 kg;
Then:
[tex]10 = 250 e^{-0.000462t}[/tex]
[tex]0.04 = e^{-0.000462t}[/tex]
From both sides, finding the natural logarithm, we have:
In(0.04) = -0.000462t
[tex]t = \dfrac{In(0.04)}{-0.000462}[/tex]
t = 6967.26
Thus, it will take approximately 6967 years for a 250 kg radium sample to get reduced to 10 kg.
Please type out all of your calculations for this dilution equation: In your vitamin C experiment, it calls for a 5% concentration of iodine. However, your 7 fluid oz. tincture of iodine contains 70% iodine. How would you dilute this
Answer:
The original7 fluid oz. 70% tincture of iodine is diluted to 98 fluid oz. to obtain a 5% solution.
Explanation:
Dilution is a technique employed in experimental sciences such as chemistry and biochemistry as well as in medicine to obtain a less concentrated solution from a more concentrated one.
The dilution formula is the most important formula required in dilution. The dilution formula is given as: C1V1 = C2V2
Where C1 is the initial concentration of the stock solution;
V1 is the volume of the stock solution required;
C2 is the final concentration of the diluted solution to be prepared;
V2 is the final volume of the diluted solution.
Using the dilution formula to determine the answer to the above question:
C1 = 70% = 0.7; V1 = 7 fluid oz.; C2 = 5% = 0.05; V2 = ?
To determine V2, it is made subject of the dilution formula:
V2 = C1V1/C2
V2 = (0.7 × 7) / 0.05
V2 = 98 fluid oz.
Therefore, the original7 fluid oz. 70% tincture of iodine is diluted to 98 fluid oz. to obtain a 5% solution.
How many grams of oxygen are necessary to react completely if you have 4.0 moles of oxygen
Answer:
1.3 × 10² g
Explanation:
Step 1: Given data
Moles of oxygen: 4.0 mol
Step 2: Calculate the mass corresponding to 4.0 moles of oxygen
For a given chemical reaction, we need 4.0 moles of oxygen and we want to find what mass in grams it represents. To convert moles to mass, we need a conversion factor: the molar mass. The molar mass of oxygen is 32.00 g/mol.
4.0 mol × 32.00 g/mol = 1.3 × 10² g