1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
belka [17]
2 years ago
8

What’s the star made up of challenge?

Chemistry
1 answer:
Crank2 years ago
4 0

Answer:

Stars are made of very hot gas. This gas is mostly hydrogen and helium, which are the two lightest elements. Stars shine by burning hydrogen into helium in their cores, and later in their lives create heavier elements.Stars are huge celestial bodies made mostly of hydrogen and helium that produce light and heat from the churning nuclear forges inside their cores.

You might be interested in
Calculate the osmotic pressure associated with 50.0 g of an enzyme of molecular weight 98 g/mol dissolved in water to give 2600
andrew-mc [135]

Answer:

π = 4,882 atm

Explanation:

To calculate the osmotic pressure (π), the <em>Van´t Hoff equation</em> must be used, which is:

π x V = n x R x T

<em>Where: </em>

• π: Osmotic pressure, which is the difference between the levels of the solution and the pure solvent through a semipermeable membrane, which allows the passage of the solvent but not the solute

• V: Volume of the solution, in liters unit

• n: Number of moles of solute

• R: Constant of ideal gases, equal to 0.08206 L.atm / mol.K

• T: Absolute temperature, in Kelvin degrees

With the data you provide you can calculate the osmotic pressure by clearing it from the equation, we would be equal to:

π = (n x R x T) / V

However, all data must first be converted to the corresponding units in order to replace the values ​​in the equation.

<em>Solution volume ⇒ go from mL to L: </em>

1000 mL of solution ____ 1 L

2600 mL of solution _____ X = 2.6 L

Calculation: 2600 mL x 1 L / 1000 mL = 2.6 L

<em>Temperature ⇒ Go from ° C to K </em>

T (K) = t (° C) + 273.15 = 30.0 ° C + 273.15 = 303.15 K

<em>Number of moles of solute ⇒</em> <em>It can be calculated since we have the mass of the enzyme and its molecular mass: </em>

98.0 g of enzyme ____ 1 mol

50.0 g of enzyme _____ X = 0.510 moles

Calculation: 50.0 g x 1 mol / 98.0 g = 0.510 moles

Now, you can replace the values ​​in the Van´t Hoff equation and you will get the result:

 π = (n x R x T) / V

π = (0.510 mol x 0.08206 L.atm / mol.K x 303.15 K) / 2.6 L = 4.882 atm

Therefore, <em>the osmotic pressure will be 4,882 atm</em>

3 0
3 years ago
Elements with atomic numbers 7 and 83 have how many valence electrons? *
IRINA_888 [86]

Explanation:

element with atomic numbers 7 and 83 have 5 and 5 valence electrons

5 0
2 years ago
Give the number of protons, neutrons and electrons in 99Tc
miss Akunina [59]

Explanation:

Tc - 99 is technetium 99.

It is a radioactive element that decays spontaneously. It has a half-life of 211,000 years and decays to stable ruthenium.

  • On the periodic table, it has an atomic number of 43;

Mass number  = 99

Atomic number = number of protons = number of electrons in atom

  Number of protons in Tc is 43

                      electron is 43

Mass number = number of protons + number of neutrons

  Number of neutrons = mass number - number of protons = 99-43 = 56

learn more:

Atomic number brainly.com/question/2057656

#learnwithBrainly

5 0
3 years ago
What geopolitical process returns carbon to the atmosphere in the from of carbon dioxide
musickatia [10]

Answer:

Explanation:

Recall that plants use water, atmospheric carbon dioxide, and energy from the sun to build their organic framework through photosynthesis. Therefore, plants draw down atmospheric carbon dioxide as part of their life habit. When plants die, the organic matter is oxidized and carbon dioxide is returned to the atmosphere.

3 0
3 years ago
What is a substance?
shusha [124]

I think the answer is C. An element or compound that cannot be physically separated. Sorry if im wrong.

7 0
3 years ago
Other questions:
  • After a hormone enters the bloodstream, it is transported throughout the body, but the hormone only affects certain cells. The r
    6·1 answer
  • Explain how the atoms of one element differ from those of another element. explain how the atoms of one isotope differ from thos
    13·1 answer
  • Solve for t In(A/B) -kt where B-1.65 x 102 M A 1.00 x 10 M. k-4.80 x 104s* and t=
    13·1 answer
  • Given the reaction:
    9·2 answers
  • What element has the lowest melting point
    12·1 answer
  • I need help with this question <br> I will give brainliest if you get it right
    15·1 answer
  • How many molecules are in 54.0 grams of CO2?
    8·1 answer
  • How many moles are equal to 3.5 grams of beryllium
    11·1 answer
  • An area where material from deep within Earth's mantle rises to the crust and melts to form magma is called a
    11·1 answer
  • A stainless steel knife has a mass of 849 grams. It has a density of 7.86 g/cm³. What is the volume of the knife?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!