Answer:
Hubble's law says that the universe is expanding outward.
Explanation:
Actually Hubble's law was discovered before the Big Bang theory was formulated. The Big Bang Theory is an attempt to explain the observations that led to Hubble's Law.Before the 1900s the theory was that the universe was eternal and self existent. The idea was that the universe was in a steady state having always existed and would always continue to exist. Albert Einstein even changed the equations in his general theory of relativity to reflect the idea of a steady state. Later he called putting in a fudge factor to result in a steady state the worse mistake of his life.
Hubble observed that most of the universe has a red shift indicating that the universe is expanding and moving away from itself. The further out that the universe is observed the faster it is moving apart.
These observations were inconsistent with a steady state universe.
The Big Bang theory extrapolated backwards. If the universe is expanding and spreading out from itself then further back in time the universe was closer together. The Theory explained Hubble's observations by the idea that at the beginning of time ( for our universe) all the matter and energy were together in one place.
This super dense ball of matter and energy then exploded outwards creating space and time as it is presently observed. The question was would the forces of gravity and black holes bring the matter and energy back together again. The answer found in 1998 was no. The rate of the expansion of the universe is increasing not slowing down and the universe will not collapse back into the super dense ball of matter that it began as.
The Big Bang Theory postulated based on the empirical evidence that our universe had a beginning and it will eventually cease to exist. The conclusion based on Hubble's observations is that matter and energy are not eternal and self existent.
When 577 J of energy is added to 32.3 g of aluminum at 17.4ºC, the temperature increases to 46.6ºC. What is the specific heat of aluminum?
Answer:
0.612 J/g°C
Explanation:
Using the formula as follows:
Q = m × c × ∆T
Where;
Q = amount of heat (Joules)
m = mass of substance (g)
c = specific heat capacity (J/g°C)
∆T = change in temperature (°C) i.e. final - initial temperature
According to the information provided in this question;
Q = 577 J
m = 32.3 g
c = ?
Final temp = 46.6ºC, initial temp. = 17.4°C
∆T = (46.6 - 17.4) = 29.2°C
Using Q = m × c × ∆T
c = Q ÷ m.∆T
c = 577 ÷ (32.3 × 29.2)
c = 577 ÷ 943.16
c = 0.6117
c = 0.612 J/g°C
What is the total number of nitrogen atoms in two mol of NH4NO3?
Answer:
the answer is B if one mol contains of NH4NO3 contains 6.02X 10^23
help people i really need this
Calculate the [H+] concentration for a solution with a pH of 6.4
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Answer: 3.98 x 10^-7
Explanation:
I hope this helped!
<!> Brainliest is appreciated! <!>
- Zack Slocum
*☆*――*☆*――*☆*――*☆*――*☆*――*☆*――*☆*――*☆**☆*――*☆*――*☆*――*☆
Match the function to the part of the cell.
1.lysosome
A.serves as a temporary storage area for nutrients and waste materials
2.vacuole
B.breaks down waste materials
3.chloroplast
C.converts energy from the sun to food energy
Answer: Chloroplast: Converts energy from the sun to food energy
Answer: Vacuole: Servers as a temporary storage area for nutrients and waster materials.
Answer: Lysosome: Breaks down waste materials
Explanation: Dude above me is wrong
Chromium is manufactured by heating a mixture of chromium(III) oxide with aluminium powder.
Cr2O3(s) + 2Al(s) → 2Cr(s) + Al2O3(s)
a=Calculate the mass of aluminium needed to react with 50 g of Cr2O3.
b=Calculate the mass of chromium produced from 50 g of Cr2O3.
c=Calculate the mass of chromium produced from 5 kg of Cr2O3.
d=Calculate the mass of chromium produced from5 tonnes of Cr2O3.
Note: 1 tonne = 1,000,000 g
Ar: Cr = 52, O = 16, Al = 27
2C2H2 + 502 = 4CO2 + 2H20
when 20000g of 2C2H2 + 5O2 = how much 4CO2?
Answer:
6.761 × 10⁴ g
Explanation:
Step 1: Write the balanced combustion reaction
2 C₂H₂ + 5 O₂ ⇒ 4 CO₂ + 2 H₂O
Step 2: Calculate the moles corresponding to 20000 g of C₂H₂
The molar mass of C₂H₂ is 26.038 g/mol.
20000 g × 1 mol/26.038 g = 768.11 mol
Step 3: Calculate the moles of CO₂ produced from 768.11 moles of C₂H₂
The molar ratio of C₂H₂ to CO₂ is 2:4.
768.11 mol C₂H₂ × 4 mol CO₂/2 mol C₂H₂ = 1536.2 mol CO₂
Step 4: Calculate the mass corresponding to 1536.2 moles of CO₂
The molar mass of CO₂ is 44.01 g/mol.
1536.2 mol × 44.01 g/mol = 6.761 × 10⁴ g
Use the following balanced reaction to solve:
P4 (s) + 6H2 (g) → 4PH3 (g)
How many grams of phosphorus trihydride will be formed by reacting 60 L of Hydrogen gas with an excess of P4?
Answer: 60.7 g of [tex]PH_3[/tex] will be formed.
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given volume}}{\text{Molar volume}}[/tex]
[tex]\text{Moles of} H_2=\frac{60L}{22.4L}=2.68moles[/tex]
The balanced chemical reaction is
[tex]P_4(s)+6H_2(g)\rightarrow 4PH_3(g)[/tex]
[tex]H_2[/tex] is the limiting reagent as it limits the formation of product and [tex]P_4[/tex] is the excess reagent.
According to stoichiometry :
6 moles of [tex]H_2[/tex] produce = 4 moles of [tex]PH_3[/tex]
Thus 2.68 moles of [tex]H_2[/tex] will produce=[tex]\frac{4}{6}\times 2.68=1.79moles[/tex] of [tex]PH_3[/tex]
Mass of [tex]PH_3=moles\times {\text {Molar mass}}=1.79moles\times 33.9g/mol=60.7g[/tex]
Thus 60.7 g of [tex]PH_3[/tex] will be formed by reactiong 60 L of hydrogen gas with an excess of [tex]P_4[/tex]
Which compound is more soluble in water at 25°C?
A.
MgF2 (Ksp = 5.2 x 10-11)
B.
SrF2 (Ksp = 7.9 x 10-10)
C.
AgBr (Ksp = 5.0 x 10-13)
D.
Agl (Ksp = 1.5 * 10-16)
Answer:
B
Explanation:
The solubility depends on the ksp. As the value of ksp increases the compound becomes more and more soluble.
In the options, the highest ksp value is 10^-10, thus that one is the most soluble.
Where do most of the rivers in North Carolina flow to?
what happens when ?? Fresh red flower is introduced into a vessel contain Sulphur dioxide along
with moisture.
A student places 2 mL of 2% ethanolic silver nitrate solution into test tube. They add 2 drops of an unknown compound into the test tube while gently mixing. After five minutes, the student heated the test tube in a water bath and a white precipitate formed. They added 2 drops of 1 M nitric acid to the mixture which was cooled to room temperature and still noticed the precipitate did not dissolve in response to the nitric acid. What compound is most likely the unknown
Answer:
hi
Explanation:
i am smart but i need this app cuz some are realy hard
can you help me please I would love that
Answer:
what are you confused on?
Which of the following is a homogeneous mixture ?A.pizza B.oxygen
C.tea
D .pure water
I think it would be d bc water is everywhere
What is h+ concentration associated with a pH=10.2
A. 10.9
B. 6.3*10^-11
C. 3.1
D. 3.2 * 10^-3
Answer:
6.3*10^-11
no reasoning i just know thats the answer you dont have to trust me.
It is often possible to change a hydrate into an anhydrous compound by heating it to drive off the water (dehydration). A 45.91 gram sample of a hydrate of MnSO4 was heated thoroughly in a porcelain crucible, until its weight remained constant. After heating, 37.07 grams of the anhydrous compound remained. What is the formula of the hydrate
Answer: The formula of the hydrate is [tex]MnSO_4.2H_2O[/tex]
Explanation:
Decomposition of hydrated manganese sulphate is given by:
[tex]MnSO_4.xH_2O\rightarrow MnSO_4+xH_2O[/tex]
Molar mass of [tex]MnSO_4[/tex] = 151.0 g/mol
According to stoichiometry:
(151.0+18x) g of [tex]MnSO_4.xH_2O[/tex] decomposes to give 151.0 g of [tex]MnSO_4[/tex]
Thus 45.91 g of [tex]MnSO_4.xH_2O[/tex] decomposes to give= [tex]\frac{ 151.0}{151.0+18x}\times 45.91g[/tex] of [tex]MnSO_4[/tex]
Also we are given : 37.07 g of [tex]MnSO_4[/tex] is produced
Thus we can equate the two equations:
[tex]\frac{ 151.0}{151.0+18x}\times 45.91=37.07[/tex]
[tex]x=2[/tex]
Thus the formula of the hydrate is [tex]MnSO_4.2H_2O[/tex]
What is Heat? What is Cold?
Answer:
Heat is the process of something getting hot(temperatures going up). Cold is when something gets cold(temperature decreases).
Explanation:
depression what are the effects to the brain
The force of gravity can act between two people.
True or false??
7x[(7+7)divide7]
PLEASE HELP
Answer:
ik this isnt the answer but mathwa will solve all yours problems
Explanation:
True or false silicon is a nonmetal
Answer:
True , Silicon is a nonmetal
If 43.1 g of O2 and 6.8 g of CO2 are placed in a 13.7 L container at 34 degrees C, what is the mixture of gasses?
answer must be in atm
Answer:
The total pressure of the gas mixture = 2.76 atm
Note: The question is not complete. The complete question is as follow:
If 43.1 g of O2 and 6.8 g of CO2 are placed in a 13.7 L container at 34 degree Celsius , what is the pressure of the mixture of gases?
Explanation:
Mass of O₂ gas = 43.1 g, molar mass of O₂ gas = 32.0 g/mol
Number of moles of O₂ gas = 43.1/32.0 = 1.347 moles
Mass of CO₂ gas = 6.8 g, molar mass of CO₂ gas = 44.0 g
Number of moles of CO₂ gas = 6.8/44 = 0.155 moles
Total number of moles of gas mixture, n = (1.347 + 0.155) = 1.502 moles
Volume of gas mixture, V = 13.7 L
Temperature of gas mixture, T = 34 °C = (273.15 + 34) K = 307.15 K
Pressure of gas mixture = ?
Molar gas constant, R = 0.0821 liter·atm/mol·K.
Using the ideal gas equation: PV =nRT
P = nRT/V
P = (1.502 × 0.0821 × 307.15) / 13.7
P = 2.76 atm
Therefore, the total pressure of the gas mixture = 2.76 atm
Given that C = n/V. And you have n=2 and C=4 what does V= ??
1...0.5
2...2
3...4
4...8
or5...Dont know
Solubility is the mass in a given volume of a substance.
True
False
Answer: True
Explanation:
For each of the solutions from above order the following in increasing polarity (from lowest to highest): solvent, more polar molecule, less polar molecule, silica gel. If the difference cannot be determined, indicate this by entering N/D. Note you might have to use a bit of logic and consider the properties of each. Useful information is found in the lab manual and student guide.
Solution % %Ethyl Lowest Next Lowest Next Highest Highest Number Hexane Acetate Polarity Polarity Polarity Polarity 1 100 0 4 75 25 3 50 50 5 5 25 75 2 0 100
Answer:
Solvent, less polar molecule, more polar molecule, silica gel
Explanation:
Solvent has lowest polarity but less polar molecule has more polarity than solvent. The more polar molecule has higher polarity value whereas silica gel has the highest polarity. The polarity of compounds is due to the difference of electronegativity values of the elements that bonded with each other. The difference of electronegativity value is high between silicon and oxygen is responsible for high polarity of silica gel.
How does pollution affect Earth Systems.
ILL GIVE BRAINLIEST!!!!!!
Answer:
pollution causes smog
Smoke fog, or smog for short, is a type of intense air pollution.
it makes GHG wich is greenhouse gas and it makes the smog to stay inside the earth wich heats the Earth and it causes flood, storm, tornadoes, ect.
1) Give all the mole-to-mole relationships (ratios) that exist in fraction form for the following reaction. (12 total) 2 Li2O2 + 2 CO2 2 Li2CO3 + O2
Answer:
1 mol Li₂O₂/mol CO₂ or 1 mol CO₂/mol Li₂O₂
2 mol Li₂CO₃/mol O₂ or 1 mol O₂/2 mol Li₂CO₃
1 mol Li₂O₂/mol Li₂CO₃ or 1 mol Li₂CO₃/mol Li₂O₂
2 mol Li₂O₂/mol O₂ or 1 mol O₂/2 mol Li₂O₂
1 mol CO₂/mol Li₂CO₃ or 1 mol Li₂CO₃/mol CO₂
2 mol CO₂/mol O₂ or 1 mol O₂/2 mol CO₂
Explanation:
The balanced chemical equation is:
2 Li₂O₂ + 2 CO₂ → 2 Li₂CO₃ + O₂
The mole-to-mole relationships are provided by the chemical stoichiometric coefficients (2 for Li₂O₂, 2 for CO₂, 2 for Li₂CO₃ and 1 for O₂).
We have to relate the moles of 1 compound to the moles of another compound in the equation. So, we can start writing the relationships between reactants (Li₂O₂ and CO₂)
2 moles of Li₂O₂ react with 2 moles of CO₂ → 2 mol Li₂O₂/2 mol CO₂= 1 mol Li₂O₂/mol CO₂ or 1 mol CO₂/mol Li₂O₂
Now, the relationships between products (Li₂CO₃ and O₂):
2 moles of Li₂CO₃ are produced when 1 mol of O₂ produced → 2 mol Li₂CO₃/1 mol O₂= 2 mol Li₂CO₃/mol O₂ or 1 mol O₂/2 mol Li₂CO₃
Finally, between reactants and products:
2 moles of Li₂O₂ produce 2 moles of Li₂CO₃ → 2 mol Li₂O₂/2 mol Li₂CO₃= 1 mol Li₂O₂/mol Li₂CO₃ or 1 mol Li₂CO₃/mol Li₂O₂
2 moles of Li₂O₂ produce 1 mol of O₂ → 2 mol Li₂O₂/1 mol O₂= 2 mol Li₂O₂/mol O₂ or 1 mol O₂/2 mol Li₂O₂
2 moles of CO₂ produce 2 moles of Li₂CO₃ → 2 mol CO₂/2 mol Li₂CO₃= 1 mol CO₂/mol Li₂CO₃ or 1 mol Li₂CO₃/mol CO₂
2 moles of CO₂ produce 1 mol of O₂ → 2 mol CO₂/1 mol O₂= 2 mol CO₂/mol O₂ or 1 mol O₂/2 mol CO₂
In the reaction 2 H, Ł02 → 2 H, O, what is the mole ratio of hydrogen to water?
A 2:2
B 2:1
C 1:2
D 4:4
A
because both have 2's in front of them
You heat water and olive oil in two separate pans for a delicious new pasta recipe. The pans are the same temperature, but only the water is boiling! Why?
A
Olive oil has weaker intermolecular forces than water. This makes the intermolecular forces in oil easier to break, and keeps the molecules stuck together in a liquid state.
B
Water has weaker intermolecular forces than olive oil. This makes the intermolecular forces easier to break, allowing the individual water molecules to separate and change to a gas.
C
Water is losing electrons more quickly than olive oil is. The electrons float to the surface of the water, and their movement allows the phase change to happen.
Answer:
I think A is the correct answer
Answer: the answer is B 100%
How do I tell my crush I like them...
Answer:
You can tell them on April Fools and if they reject you just say April Fools.
Answer: if u do it on text just say oh wrong person or something I’m not sure
Explanation: