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3 years ago

in a chemical change how does the total energy of the reactants compare to the total energy of the products

Chemistry

1 answer:

jeka57 [31]3 years ago

8 0

Answer:

Explanation:

All chemical changes requires a substantial amount of energy. Depending on the type of reaction, the energy of reactants and products differs.

In an exothermic chemical change where heat is always given off to the surroundings, the energy of the product is less than that of reactants.

For endothermic changes, the surrounding becomes colder at the end of the reaction. This implies that the heat energy of the product is higher than that of the reactants.

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NaOH is an Arrhenius base because it increases the concentration of hydroxide ions when dissolved in solution.

Licemer1 [7]

The answer is true, NaOH is and Arrhenius base.

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3 years ago

Read 2 more answers

A sample of xenon gas occupies a volume of 5.24 L at 411 K. If the pressure remains constant, at what temperature will this

stiks02 [169]

Answer:

161.57 K

Explanation:

V1/T1 = v2/T2

(5.24 L)/(411 K) = (2.06 L)/T2

T2 = 161.57 K

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2 years ago

Using your old and new reaction roadmaps as a guide, show how to convert ethane into 1- butanol. You must use ethane as the sour

Naddik [55]

Answer:

Ethane can be converted into 1- butanol in 4 different steps and reactions.

Explanation:

Step 1 : Ethane follows Markovnikov's rule and reacts with a protic acid called Hydrogen chloride to form Chloroethane.

Step 2: Chloroethane undergoes Wurtz reaction where it reacts with sodium metal in the presence of dry ether to form an higher alkane called butane.

Step 3: Butane undergoes chlorination where it reacts with an halogen called chlorine to form 1-chlorobutane.

Step 4: 1-chlorobutane reacts strong aqueous Potassium hydroxide (KOH) to form 1-butanol.

Attached to this answer is the handwritten conversion of Ethane to 1-butanol showing all the reagents and molecules synthesized along the way.

5 0

3 years ago

Pyridine, C5H5N, is a bad-smelling liquid that is a weak base in water. Its pKb is 8.77. What is the pH of a 0.20 M aqueous solu

kari74 [83]

Answer:

pH = 9.26

Explanation:

Let's make the reaction of this weak base:

C₅H₅N + H₂O ⇄ C₅H₅NH⁺ + OH⁻ Kb

We do not know the Kb, but we can discover it from pKb

Kb = 10^⁻pKb → 10⁻⁸'⁷⁷ = 1.70×10⁻⁹

So, let's make the expression for Kb

Kb = [OH⁻] . [C₅H₅NH⁺] / [C₅H₅N]

In the equilibrum, we would have 0.20 moles from the begining - x (react)

So we would proudce x moles of OH⁻ and x moles of C₅H₅NH⁺.

In conclussion:

1.70×10⁻⁹ = x . x / (0.20 - x)

To avoid the quadratic formula we can miss the x from the substraction

1.70×10⁻⁹ = x² / 0.20

1.70×10⁻⁹ . 0.20 = x²

We avoid the x from the (0.20-x), because the base is so concentrated, and Kb is very small.

x = √(1.70×10⁻⁹ . 0.20) → 1.84×10⁻⁵

That's the value of [OH⁻], so we can calculate pOH

- log [OH⁻] = pOH → - log 1.84×10⁻⁵ = 4.73

Then pH = 14 - pOH

14 - 4.73 = 9.26

4 0

4 years ago

What is the concentration of hydrogen ion with the poh of 11.5

ankoles [38]

PH +pOH = 14

(14 - 11.5) = 2.5 (the ph is 2.5)

NOW, Ph = -lg (H*)

apply the formula

6 0

3 years ago