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3 years ago

What happens in a chemical change that does not occur in a physical change?

Chemistry

1 answer:

Andrej [43]3 years ago

6 0

Answer:

In a chemical reaction, there is a change in the composition of the substances in question; in a physical change there is a difference in the appearance, smell, or simple display of a sample of matter without a change in composition. Although we call them physical "reactions," no reaction is actually occurring.

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Which is regarding enzyme inhbition

lys-0071 [83]

Explanation:

An enzyme inhibitor is a molecule that binds to an enzyme and decreases its activity. ... Since blocking an enzyme's activity can kill a pathogen or correct a metabolic imbalance, many drugs are enzyme inhibitors. They are also used in pesticides.

7 0

3 years ago

Using wolfram alpha or some other reference, determine which of these elements would be liquid at 525 k (assume samples are prot

romanna [79]

The choices for this problem are bismuth, Bi; platinum, Pt; selenium, Se; calcium, Ca and copper, Cu. I think the correct answer would be selenium. The melting point of bismuth is at a temperature of 544.4 Kelvin. At a temperature of 525 K, it would exist as solid. Platinum melts at 2041.1 K. At 525 K, platinum would be in solid form. Selenium has a melting point at 494 K so that at a temperature of 525 K, it would exist in its liquid state. Calcium has a melting point of 1112 K so it would exist as solid at 525 K. Copper has a melting point at 1358 K, so it would still exist as solid at a temperature of 525 K. Therefore, the answer would only be selenium.

3 0

3 years ago

10. Make your own unique problem for your classmates to solve for the

babymother [125]

Answer:

Explanation:

<u>Problem</u>:

In a gender based experiment, the blood pressure of different ages of men is been checked and recorded to determine if there is any correlation. What will be the independent, dependent and controlled variables?

<u>Answer</u>:

A controlled variable is the variable that is left constant throughout the course of an experiment. The controlled variable here is the gender.

A dependent variable is the variable that is been determined or measured during the course of an experiment. The dependent variable here is the blood pressure.

An independent variable is the variable that is intentionally or decidedly altered during the course of an experiment. The independent variable here is the age.

3 0

3 years ago

A balloon has a volume of 1.75L at a temperature of 298K. What will be the volume of the balloon if you take it out into the win

lozanna [386]

Answer:

1.52 L

Explanation:

P1V1T2=V2P2T1

V2=V1T2/T1

Fill in with given values then solve

We can check this by knowing that V and T at constant P have a proportional relationship. Hence, this is correct.

- Hope that helped! Please let me know if you need further explanation.

7 0

3 years ago

What is the standard enthalpy of a reaction for which the equilibrium constant is (a) doubled, (b) halved when the temperature i

Alexxandr [17]

Answer:

a) 48KJ

b) -48KJ

Explanation:

Given that;

ln(K2/K1) = ΔH°/R(1/T2 - 1/T1)

K2= equilibrium constant at T2

K1 = equilibrum constant at T1

R = gas constant

T1 = initial temperature

T2 = final temperature

When we double the equilibrium constant K1; K2 = 2K1

T1 = 310 K

T2 = 310 + 15 = 325 K

ln(2K1/K1) =- ΔH°/R(1/T2 - 1/T1)

ln2 = -ΔH°/8.314(1/325 - 1/310)

0.693 = -ΔH°/8.314(3.08 * 10^-3 - 3.2 * 10^-3)

0.693 = -ΔH°/8.314 (-0.00012)

0.693 = 0.00012ΔH°/8.314

0.693 * 8.314 = 0.00012ΔH°

ΔH° = 0.693 * 8.314/0.00012

ΔH° = 48KJ

b) K2 =K1/2

ln(K1/2/K1) =- ΔH°/R(1/T2 - 1/T1)

ln (1/2) = -ΔH°/8.314 (1/325 - 1/310)

-0.693 = -ΔH°/8.314 (-0.00012)

-0.693 = 0.00012ΔH°/8.314

-0.693 * 8.314 = 0.00012ΔH°

ΔH°= -0.693 * 8.314/0.00012

ΔH°= -48KJ

6 0

3 years ago