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.
Plssss help ASAP I really need help with this y’all I’m bad at science
how do you melt water FREE 100 POINTS
Answer:
by adding heat
Explanation:
Adding heat can cause ice (a solid) to melt to form water (a liquid). Removing heat causes water (a liquid) to freeze to form ice (a solid).
by adding heat
when water was changes to soild or a gas , we say change to a different state of the matter. Even though the waters physical from change its molecular stay the same
How many fluorine atoms are there in 39.4 moles of CF4?
Answer:
here
Explanation:
Answer: 4
A molecule of carbon tetrafluoride, CF4 , is made up of 1 carbon atom bonded to 4 fluorine atoms. Each carbon atom weighs 12.0 amu and each fluorine atom weighs 19.0 amu so 1 CF4 molecule weighs 1×12.0 amu + 4×19.0 amu = 88.0 amu. This number, 88.0, is called the molecular weight (or molecular mass) of CF4.
I don’t understand please help
when forces act in equal and opposite directions the net force is and the object
Answer:
Equal forces acting in opposite directions are called balanced forces. Balanced forces acting on an object will not change the object's motion. When you add equal forces in opposite direction, the net force is zero.
Explanation:
2.0M Propionic Acid HC3H5O2 Dissolves In Distilled Water. If It Has A Ka Of 1.3*10-5, What Is The Final PH?
The base ethylamine C2H5NH2 has a Kb of 5.6*10-4. What will the pH be in .53 molar solution?
Answer: first you have to calculate the amount ionized. We will say it is x mol / L
then % ionization = (amount ionized / initial concentration) * 100%
x can be calculated using an ice chart
HC3H5O2 -----> H+ + C3H5O2-
Initial HC3H5O2 = 0.250
change = -x
equilibrium = 0.250 - x
initial H+ = 0
change = +x
equilibrium = x
C3H5O2- initial = 0
change = +x
equilibrium = x
Ka = [H=][C3H5O2-] / HC3H5O2]
1.3 * 10 ^ -5 = [x][x] / (0.250 - x)
So 1.3 * 10 ^ -5 * (0.250 - x) = x ^ 2
3.25 * 10^ -6 - (1.3 * 10^-5)x = x^2 now this is a quadratic equation and you have to rearrange it and solve for x
x^2 + 1.3 * 10^-5)x - 3.25 * 10^ -6 = 0
use the equation x = {-b (+ or -)[b^2 - 4.a.c] ^ 1/2} / 2a
you should get x = 1.80 * 10 ^ -3 or x = -1.80* 10^-3
but x can not be negative..
so x = 1.80 * 10 ^ -3
so percent ionization = (1.80 * 10 ^ -3 / 0.250) * 100%
=0.72 %
the other way which is more easier is
assuming that x is very small and therefore 0.250 - x is approximately equals to 0.250
then 1.3 * 10^-5 = x^2 / 0.250
so x^2 = 1.3 * 10^-5 * 0.250
x = 1.80 * 10 ^-3
then percent ionization is = (1.80 * 10 ^ -3 / 0.250) * 100%
=0.72 %
if the percent ionization is > 5 % you can not do that approximation. in such a case you have to solve the quadratic equation. that is why I showed both methods.
now you can do the parts b and c
b answer : percent ionization = 1.27 %
c answer : 2.54%
good luck
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.
You have 281 kilojoules how many kilocalories is it need to know ASAP
Solution Mass of NaCl (9) Volume of water (mL)
A
5.0
50.0
B
5.0
75.0
с
5.0
100.0
D
5.0
125.0
Which of the solutions has the highest salt concentration?
O A Solution B
B. Solution A
O
C. Solution C
D. Solution D
Divide the volume of water with mass of salt and multiply with 100 you'll get the concentration percentage
answer is B, because solution A's percentage is 10%
brainliest plz
What is thePercent composition of dichlorine heptoxide?
Answer:
The percent composition of dichlorine heptoxide is 38.76% CI and 61.24% O
Answer:
38.76%cl and 61.24%o
Explanation:
the percent composition of dichlorine heptoxide is 38.76%Cl and 61.24%O
What is the molality of a 10.0 % by mass solution of NaCl?
(molar mass of NaCl = 58.44 g/mol)
mol/kg
On CK-12 all of these answers are correct
1.9
1.888
1.89
1.88
The molality of a 10.0 % by mass solution of sodium chloride (NaCl) is 1.7M.
How do we calculate molarity?Molarity of any solution will be calculated as number of moles of solutes present in per litre of the solution.
Moles of the substance will be calculated as:
n = W/M, where
W = given mass
M = molar mass
Given that percent mass of NaCl = 10% i.e. 10g of NaCl is present in 100 g of solution.
We know that 1 g = 0.001 L
100 g = 0.1 L
Moles of NaCl = 10g / 58.44g/mol = 0.17 mol
Molarity of NaCl = 0.17 / 0.1 = 1.7M
Hence required molarity is 1.7 M.
To know more about molarity, visit the below link:
https://brainly.com/question/489225
A helium nucleus with two protons and two neutrons is called a(n)
A. alpha particle
B. beta particle
C. electroscope
D. gamma ray
Clear selection
Answer:
Explanation:
Alpha particles,
How many electrons and protons does the sodium ion have 11 protons and 11 electrons
Answer:
A sodium ion Na+ contains 10 electrons, 11 protons, and 12 neutrons.
Explanation:
ionization of sodium dichromate
Explanation:
this is the answer of your question .
hope it helped you
Of the three Intermolecular forces, the type with the largest dissociation energy is ________.
A. Dipole-dipole interactions
B. Dispersion forces
C. Hydrogen bonds
Answer:
C. Hydrogen bonds
Explanation:
Strongest intermolecular force
Hydrogen Bonding (H-Bonding)
Hydrogen bonds are caused by highly electronegative atoms. They only occur between hydrogen and oxygen, fluorine or nitrogen, and are the strongest intermolecular force.
Answer: C hydrogen bonds
Explanation:
5.07 x 10^24 atoms of antimony is how many moles?
8.98 mol
7.99 mol
4.82 mol
8.42 mol
Answer:
8.42 moles (3 sig. figs.)
Explanation:
Given 5.07 x 10²⁴ atoms of antimony (Sb) => ? moles Sb
1 mole of any substance contains 6.02 x 10²³ particles ( atoms or molecules)
∴ Think in terms of 'how many 6.02 x 10²³'s are in 5.07 x 10²⁴ atoms Sb?
That is => moles Sb = 5.07 x 10²⁴ atoms Sb / 6.02 x 10²³ atoms Sb/mole Sb
= 8.42192691 moles Sb (calculator answer) ≅ 8.42 moles (3 sig. figs.)
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
depression what are the effects to the brain
Which of the following is the best hypothesis?
A. If paper is burned, the products will be carbon dioxide and water.
B. At what temperature does a piece of notebook paper start to burn?
C. Some people use burning paper to help get a campfire started.
D. You should recycle paper instead of burning it.
Answer:
THE CORRECT ANSWER IS A
sorry for caps
How many moles of LiOH are in a 4.5 M solution containing 1.5 L of water?
Answer:
d
Explanation:
The mass of a salt in grams that will dissolve in 100 mL of water.
____________ A solution that has dissolved the maximum amount of a compound at a given temperature. Any further addition of salt will remain undissolved.
_________ The product of the molarities of the dissolved ions, raised to a power equal to the ion's coefficient in the balanced chemical equation.
__________ A decrease in the solubility of an ionic compound as a result of the addition of a common ion.
__________ The maximum number of moles of a salt that will dissolve in 1 L of solution.
a. A decrease in the solubility of an ionic compound as a result of the addition of a common ion.
b. The mass of a salt in grams that will dissolve in 100 mL of water.
c. A solution that has dissolved the maximum amount of a compound at a given temperature. Any further addition of salt will remain undissolved.
d. The product of the molarities of the dissolved ions, raised to a power equal to the ion's coefficient in the balanced chemical equation.
e. The maximum number of moles of a salt that will dissolve in 1 L of solution.
Answer:
Solubility : The mass of a salt in grams that will dissolve in 100 mL of water
Saturated solution : A solution that has dissolved the maximum amount of a compound at a given temperature. Any further addition of salt will remain undissolved
Solubility product constant :The product of the molarities of the dissolved ions, raised to a power equal to the ion's coefficient in the balanced chemical equation
Common ion effect : A decrease in the solubility of an ionic compound as a result of the addition of a common ion
Molar solubility : The maximum number of moles of a salt that will dissolve in 1 L of solution
Explanation:
Solubility is expressed usually as the mass of solute per 100 grams or 100 ml of solvent.
Molar solubility of a solid is expressed as the concentration of the dissolved solid in a saturated solution.
Solubility product constant is defined as the equilibrium constant in which a solid ionic compound is dissolved to produce its ions in solution. It is represented as
The common-ion effect is the decrease in solubility of a sparingly soluble salt by the addition to the solution of a soluble compound with an ion in common with the precipitate.
Saturated solution is defined as the solution in which no more solute particles can be dissolved in the solvent.
The force of gravity can act between two people.
True or false??
A certain metal M forms a soluble nitrate salt M(NO3), Suppose the left half cell ofa galvanic cell apparatus is filled with a 4.00 M solution of M (NO,), and the right half cell with a 20.0 mM solution of the same substance. Electrodes made of M are dipped into both solutions and a voltmeter is connected between them. The temperature of the apparatus is held constant at 35.0 °C.
Required:
a. Which electrode will be positive?
b. What voltage will the voltmeter show?
Answer:
Explanation:
The left electrode will be positive on the grounds that focus on the concentration that the cell electron moves from a lower concentration fixation to a higher concentration. Thus right electrode will go about and act as an anode and will be negative. Also, the left electrode will be the cathode and will be positive.
The concentration cell [tex]E_{Cell} = \dfrac{-0.0591}{1} log \dfrac{0.02}{4}[/tex]
[tex]E_{Cell} =0.136 V[/tex]
= 136 mV
what is a mole and its properties
One mole of a substance is equal to 6.022 × 10²³ units of that substance (such as atoms, molecules, or ions). The number 6.022 × 10²³ is known as Avogadro's number or Avogadro's constant. The concept of the mole can be used to convert between mass and number of particles.
the form of EMR that has less energy per photon than microwaves is ____?
Answer: radio wave frequencies have longer wavelengths and smaller
Energies per photon
Identify the techniques used in the work-up and characterization of benzoic acid. The analytical method used to confirm the structure and functional groups of the product NMR spectroscopy The technique used to separate the pure product from any excess reagent, impurities, and byproducts Recrystallization The quick, numeric analysis used to characterize the product and assess the purity Melting point.
Answer:
Explanation:
[tex]\text{From the list of the options given; we are to identify the suitable techniques} \\ \\ \text{for the characterization of benzoic acid.}[/tex]
[tex]\text{The analytical method used to confirm the structure and functional groups}\\ \\ \text{present in the product is} \ \ \mathbf{IR \ spectroscopy.}[/tex]
[tex]\text{The technique used to separate pure products from any excess reagents,} \\ \\ \text{impurities, and byproducts is}\ \ \mathbf{Recrystallization.}[/tex]
[tex]\text{The quick, numeric analysis done to characterize the product and assess the purity is}[/tex][tex]\mathbf{melting \ point.}[/tex]
Consider the fatty acid. A carboxylate salt is attached to a 19 carbon chain, where double bonds are present between carbons 5 and 6, between carbons 8 and 9, between carbons 11 and 12, and between 14 and 15. The carboxylate carbon is carbon 1. All double bonds are cis. Which of the designations are accurate for the fatty acid
Answer:
ω-3 fatty acid and 19:4(Δ5,8,11,14)
Explanation:
From the image attached below:
We can see the structure of the delta nomenclature showing the numbers of carbons, numbers of double bonds, and the locations of the double bonds in the structure of the carboxylate salt.
Also, we can see the structure of the fatty acid where; the location of the first double bond from the methyl end is shown.
Hence, the designation which are accurate for these structures are:
ω-3 fatty acid and 19:4(Δ5,8,11,14)
match the following
Answer:
Ai --> Bii
Aii --> Bi
Aiii --> Bv
Aiv --> Biii
Av --> Biv
Explanation:
For Ai, naphthalene sublimes directly from a solid to gas when heated at around 80 degree Celsius.
For Aii, Ozone has a molecular formula of O₃.
For Aiii, weeds are normally considered as "unwanted" plants. Many people may consider using herbicides to clear the weeds in their gardens.
For Aiv, filtration is a physical method for separating solid and liquid from a mixture. A filter paper is normally used, in which the complex structure of the paper only allows fluid to pass through it, but not the solid ones. The solid left behind on the filter paper is called "residue".
For Av, photosynthesis is a chemical reaction that occurs in the leaves of a plant, which produces food for plants to survive. Carbon dioxide, water and light are required for photosynthesis to take place.
what is the molecular formula of a compound with the empirical SO and molecular weight 96.13?
Answer:
Explanation: A compound with the empirical formula SO has a molecular weight of 96.13
If 22.4L = I moles How many liter of CO2 are produced if you produce 9.6 moles of CO2?
Answer:
215 moles
Explanation:
[tex]9.6mol CO_{2} (\frac{22.4 L CO_{2}}{1 mol CO_{2}} ) = 215 L CO_{2}[/tex]