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2 years ago

Pls pls help Pls pls pls help

Chemistry

1 answer:

asambeis [7]2 years ago

3 0

Question 3

Explanation:

answer -A /A chemical reaction happens when substances break apart or combine to form one or more new substances. New substances form when bonds break and new bonds form. The chemical properties of the new substances are different from those of the original substances. ... Some chemical reactions produce a precipitate.

answer- B /Chemical reactions occur when chemical bonds between atoms are formed or broken. The substances that go into a chemical reaction are called the reactants, and the substances produced at the end of the reaction are known as the products

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Answer:

At equilibrium, the rate of the forward, and the reverse reactions are equal.

Explanation:

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What is meant by a chemical bond? why do atoms form bonds with each other? why do some element esist as molecules in nature inst

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How many moles of hydrogen are in 2.8 moles of caffeine

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What is the simplest alkane

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What is the activation energy (in kJ/mol) of a reaction whose rate constant increases by a factor of 89 upon increasing the temp

Setler [38]

Answer:

15.9 KJ/mol

Explanation:

Given data:

Temperature = T1 = 307 K

Temperature = T2 = 343 K

Gas constant R= 8.314 J/(mol • K)

rate constant = k2/K1 = 89

To find:

Activation energy (in kJ/mol) = Ea = ?

Formula:

The Arrhenius equation gives the relation between temperature and reaction rates:

$ln\frac{K2}{K1} = \frac{Ea}{R} (\frac{1}{T1} - \frac{1}{T2})$

here, in this equation

k = the rate constant

Ea = the activation energy

R = the Universal Gas Constant

T= the temperature

Solution:

$ln\frac{89 K1}{K1} = \frac{Ea}{8.314 J/mol . k\\} (\frac{1}{307 K} - \frac{1}{343 K})$

ln 89 = Ea / 8.314 J/mol.K x (0.0325 - 0.00291)

ln 89 = Ea / 8.314 J/mol.K x (2.95 x 10^2 )

4.488 = Ea / 8.314 J/mol.K x (2.95 x 10^2)

Ea = 4.488 x (2.95 x 10^2) / 8.314 J/mol.K

= 0.1324 / 8.314

Ea = 0.0159

Ea = 1.59 x 10^2 J/mol

= 15.9 KJ/mol

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3 years ago