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hammer [34]
2 years ago
12

There is a theory that gravity could pull galaxies back together, causing a reverse big bang.

Chemistry
2 answers:
Mrrafil [7]2 years ago
8 0

C. the expansion of the universe is accelerating

Alex787 [66]2 years ago
8 0

Answer:

C

Explanation:

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How did the uncertainty principle influence thinking about the arrangement of electrons in atoms?
pishuonlain [190]

Answer:

The correct answer is option C

Explanation:

According to Heisenberg's principle "At the instant of time when the position is determined, that is, at the instant when the photon is scattered by the electron, the electron undergoes a discontinuous change in momentum. This change is the greater the smaller the wavelength of the light employed, i.e., the more exact the determination of the position. At the instant at which the position of the electron is known, its momentum therefore can be known only up to magnitudes which correspond to that discontinuous change; thus, the more precisely the position is determined, the less precisely the momentum is known".

Hence, this principle made scientists to realize that electrons could not be located in defined orbits which a contradictory of Bohr's model.

3 0
3 years ago
Given these reactions, X ( s ) + 1 2 O 2 ( g ) ⟶ XO ( s ) Δ H = − 668.5 k J / m o l XCO 3 ( s ) ⟶ XO ( s ) + CO 2 ( g ) Δ H = +
qwelly [4]

<u>Answer:</u> The \Delta H^o_{rxn} for the reaction is -1052.8 kJ.

<u>Explanation:</u>

Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.

According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.

The given chemical reaction follows:

X(s)+\frac{1}{2}O_2(g)+CO_2(g)\rightarrow XCO_3(s)      \Delta H^o_{rxn}=?

The intermediate balanced chemical reaction are:

(1) X(s)+\frac{1}{2}O_2(g)\rightarrow XO(s)    \Delta H_1=-668.5kJ

(2) XCO_3(s)\rightarrow XO(s)+CO_2     \Delta H_2=+384.3kJ

The expression for enthalpy of the reaction follows:

\Delta H^o_{rxn}=[1\times \Delta H_1]+[1\times (-\Delta H_2)]

Putting values in above equation, we get:

\Delta H^o_{rxn}=[(1\times (-668.5))+(1\times (-384.3))=-1052.8kJ

Hence, the \Delta H^o_{rxn} for the reaction is -1052.8 kJ.

7 0
3 years ago
A balloon sits in the sunlight causing it to heat up and explode. Which of the following
luda_lava [24]
I think it’s A, the particles of gas inside the ballon move faster and decrease pressure in
6 0
1 year ago
What refers to the attractive forces that exist between molecules?​
CaHeK987 [17]
Intermolecular forces are the forces of attraction or repulsion which act between neighboring particles (atoms, molecules, or ions ). These forces are weak compared to the intramolecular forces, such as the covalent or ionic bonds between atoms in a molecule.
8 0
3 years ago
which method would be best for separating the compounds of a mixture that is made from two diffrent liquids
kobusy [5.1K]

Answer:

fractional distillation since ot depends on the different liquids to have different boiling points

5 0
2 years ago
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