In this experiment, you will measure all masses in

Read the statement about Mount Vesuvius. Mount Vesuvius erupted in 79 CE and destroyed the ancient city of Pompeii. Why is the s

Mamont248 [21]

Answer:

B

Explanation:

6 0

3 years ago

1,4-Pentadiene has a AHhydro = -254 kJ/mol while trans-1,3-pentadiene has a AHhydra = -226 kJ/mol. Explain this difference in he

julsineya [31]

Answer:

trans-1,3-pentadiene is more stable than 1,4-pentadiene due to presence of a conjugated double bond.

Explanation:

Here, $\Delta H_{hydro}=H(hydrogenated pdt.)-H(diene)$

H(hydrogenated pdt.) is same for both 1,4-pentadiene and 1,3-pentadiene as they both produce pentane after hydrogenation

H(diene) depends on stability of diene.

More stable a diene, lesser will be it's H(diene) value (more neagtive).

trans-1,3-pentadiene is more stable than 1,4-pentadiene due to presence of a conjugated double bond.

Hence, $\Delta H_{hydro}$ is higher (less negative) for trans-1,3-pentadiene

5 0

3 years ago

What is the molarity of a solution that contains 4.3 mol of acetic acid (C2H3O2) in 450. mL of solution?

lord [1]

Hey there !

Number of moles of solution: 4.3 moles

Volume in liters:

450.0 mL / 1000 => 0.45 L

Therefore:

Molarity = number of moles / volume of solution ( L)

Molarity = 4.3 / 0.45

=> 9.55 M

Hope that helps!

3 0

3 years ago

NEED HELP ON 17,18,19,20,21,22,23. ONLY IF YOU ARE POSITIVE ABOUT THE ANSWER!!!!

Alex777 [14]

Answer:

17. D. Chemical change

18. C. Cell wall

19. D. To transfer matter and energy within and between organisms.

20. A. Transporting materials

21. C. Carbon dioxide

22. A. Cellular respiration

23. C. Produce food and give off oxygen

Explanation:

I have been able to supply the correct answers. The cell wall functions as a structure that provides structural support and protection to the cell. It is tough, flexible and at times rigid. In a chemical change, new materials with new properties are manufactured. So, the process of photosynthesis is a chemical change.

The endoplasmic reticulum actually transports material. It transports materials like protein and lipids made within the cell and sends it to where they are needed.

Carbon dioxide is the the gas that animals give off and plants use it during photosynthesis. Cellular respiration involves the activities that result to the breaking down of food in order to release energy.

8 0

3 years ago

Uranium-238 decays to lead-206 with a half-life of 4.5 x 109 yr. Determine how much uranium-238 decays in milligrams (to three s

Mamont248 [21]

Answer:

2.15 mg of uranium-238 decays

Explanation:

For decay of radioactive nuclide-

$N=N_{0}.(\frac{1}{2})^{\frac{t}{t_{\frac{1}{2}}}}$

where N is amount of radioactive nuclide after t time, $N_{0}$ is initial amount of radioactive nuclide and $t_{\frac{1}{2}}$ is half life of radioactive nuclide

Here $N_{0}=4.60 mg$ , $t=4.1\times 10^{9}yr$ and $t_{\frac{1}{2}}=4.5\times 10^{9}yr$

So, $N=(4.60mg)\times (\frac{1}{2})^{\frac{4.1\times 10^{9}}{4.5\times 10^{9}}}$

so, N = 2.446 mg

mass of uranium-238 decays = (4.60-2.446) mg = 2.15 mg

3 0

3 years ago