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adelina 88 [10]
3 years ago
9

Which of the following is true about chemical reactions. A. they are accompanied by changes in energy. B. they form new substanc

es with new properties. C. both A & B
D.neither A nor B
Chemistry
1 answer:
Ilia_Sergeevich [38]3 years ago
7 0
The correct answer should be option C. hope this helps
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In order of relative atomic mass.
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The following reactions take place in the ozone layer by the absorption of ultraviolet light.
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Answer:

Option B will require a shorter wave length of light.

Explanation:

The bonding between Ozone (O3) and Oxygen (O2) can be used to explain why the breaking of oxygen into Oxygen radicals will require a shorter wave length.

  • The bond between Oxygen (O2) is a double bond while Ozone (O3) has an intermediate bond between a double bond and a single bond.
  • The bond order of Oxygen (O2) is equals 2 while that of Ozone (O3) is 1.5. Since the bond order of oxygen is higher, it will require more energy to break the bond compared to breaking the Ozone (O3) bond.
  • Recall that Energy is inversely proportional to wave length.
  • So it will require a shorter wave length to break the Oxygen (O2) into its radicals.
5 0
3 years ago
Put the level of organization in order from smallest to largest a. Organelles, cellsorgans, tissuesorgan systems b. Organs, tiss
Lesechka [4]

Answer: My guess is D i hope this is right

Explanation:

8 0
3 years ago
A) Calculate the osmotic pressure difference between seawater and fresh water. For simplicity, assume thatall the dissolved salt
never [62]

Answer:

a)  Δπ = 1.264 atm

b) W = 128 joules

c)  ΔH >> W  ( a factor greater than 17,000 )

Explanation:

a) The osmotic pressure, π , is determined by :

π = nRT/V, where n= moles of solute

                          R= 0.0821 Latm/kmol

                          T = 300 K

calling π(sw) osmotic pressure for  for sea water and π (fw) for fresh water,

salinity of sea water = 3.5 g / 1L water   (assuming only NaCl for the salts)

salinity of fresh water = 0.5 parts per thousand (range: 0- 0.5 ppt)

πsw = (3.5 g/58.44 g/mol) (0.0821 Latm/Kmol) (300 K ) /1 L = 1.475 atm

πfw = (0.5 g/58.44 g/mol) (0.0821 Latm/Kmol) (300 K ) /1 L = 0.211 atm

d water = 1 g/cm³

Δ π = (1.475 - 0.211) = 1.264 atm

b) W = Δπ V = 1.426 atm x 1L = 1.43 L-atm

1 L-atm = 101.33 j

W =  101.33 j/ Latm x  1.43 Latm = 128 joules

c) ΔH = Q₁ + nΔH vap, where

            Q₁  = heat required to bring the solution from 300 K to boiling, 373 K

            ΔH vap = heat of vaporization

Q = mCΔT = 1000 g x 4.186 j x 73 K = 305.6 j = 0.3056 kj

ΔH vap = (1000 g/ 18 g/mol ) 40.7 kj/mol = 2,261 kj

ΔH =  0.3056 kj + 2,261 kj = 2,261.3 kj

Note = Q << ΔH vap and we could have neglected it.

This result shows why nobody talks about evaporation of sea water to produce fresh water ΔH >> W

6 0
3 years ago
6. List the following particles in size order, from<br> biggest to smallest?
Arte-miy333 [17]

Answer:

the particles, molecules, and gas range from smallest to largest in the following order: electron < proton < atom <...

5 0
2 years ago
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