CHEMISTRY HIGH SCHOOL

A photon has a wavelength of 3.8 × 10-7 meters, which is between visible and ultraviolet. Calculate the energy of this photon.

Answers

Answer 1

Answer:

Answer:

Energy of the photon is $5.2* 10^(-19)$ J.

Explanation:

Energy of a photon (E) is given by the following equation-

$E=(hc)/(\lambda )$

Where h is the plank constant, c is the velocity of light and $\lambda$ is the wavelength of photon.

Hence, $E=((6.626* 10^(-34)J.s)* (3* 10^(8)m/s))/(3.8* 10^(-7)m)$

So, E= $5.2* 10^(-19)$ J

Answer 2

Answer:

use the equation Energy of photon = h * c / wavelength

where h is Planck constant = 6.62607004 × 10-34 m2 kg / s

c is velocity of light in vacuum = 3.00 × 108 m/s and

wavelength value already you know

0.004 moles

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

$n = (N)/(L) \n$

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

$n = \frac{2.4 * {10}^(21) }{6.02 * {10}^(23) } \n = 0.003986$

We have the final answer as

0.004 moles

Hope this helps you

Explain why ocean temperatures vary by location on Earth’s surface.

Answers

The sun, mostly. Remember that on one half of Earth, it is day and on the other, it is night. The sun is heating up a portion of the ocean while other parts of it are cooling down because they're not receiving heat from it. As the Earth rotates, sun exposure in the ocean varies and so does its temperature.

Select the atomic symbol that would represent an isotope with 13 protons and 14 neutrons. A. 14 16 N B. 13 6 C C. 27 14 Si D. 27 13 Al

Answers

Answer:

D. 27 13 Al

Explanation:

13 protons means atomic number 13. The periodic table says element 13 is aluminum (Al). 27 is the atomic mass, made up of 13 protons (1 each) and 14 neutrons (also 1 each) for a total of 27 atomic mass.

Given the balanced equation representing a reaction:Fe(s) + 2HCl(aq) → FeCl2(aq) + H2(g)
This reaction occurs more quickly when powdered iron is used instead of a single piece of iron of the same mass because the powdered iron
(1) acts as a better catalyst than the single piece of iron
(2) absorbs less energy than the single piece of iron
(3) has a greater surface area than the single piece of iron
(4) is more metallic than the single piece of iron

Answers

Answer: Option (3) is the correct answer.

Explanation:

One of the important factor on which rate of reaction depends is surface area. That is, when a compound is crushed into powdered form then there will be increase in surface area of the compound.

Hence, now more number of particles can interact, therefore, there will be increase in rate of reaction.

Thus, we can conclude that reaction occurs more quickly when powdered iron is used instead of a single piece of iron of the same mass because the powdered iron has a greater surface area than the single piece of iron.

What is the percent composition of calcium (Ca) in CaO?A 56g/40g x 100%
B 16g/56g x 100%
C 40g/56g x 100%
D 40g/100% x 56g

Answers

Answer:

C 40 g/56 g × 100 %

Explanation:

Calculate the mass of each component and the total mass.

Element Atomic mass/u No. of atoms Subtotal mass/u

Ca 40.08 1 40.08

O 16.00 1 16.00

Total = 56.08

The formula for mass percent is

% by mass = Mass of component/Total mass × 100 %

In this problem

% Ca = mass of Ca/mass of CaO × 100 %

% H = 40.08 g/56.08 g × 100 %

The percentage composition of calcium (Ca) in CaO is option C.

Here we have to determine the mass of every component and even the total mass.

Element Atomic mass/u No. of atoms Subtotal mass/u

Ca 40.08 1 40.08

O 16.00 1 16.00

Total = 56.08

The mass percent formula is

$\%\ by\ mass = Mass\ of\ component / Total\ mass * 100 \%$

$\% Ca = mass\ of\ Ca/ mass\ of\ CaO * 100 \%\n\n\% H = 40.08 g/ 56.08 g * 100 \%$

Therefore, we can conclude that the correct option is C.

Learn more: brainly.com/question/362440

What are the components of a phospholipid? 1) A phosphate group and two hydrophilic fatty acid tails 2) A phosphate group and two hydrophobic fatty acid tails 3) A phosphate group head and two hydrophobic fatty acid tails 4) A phosphate group head and two hydrophilic fatty acid tails

Answers

A phospholipid is composed of a polar, hydrophilic phosphate group 'head' and two hydrophobic (non-polar) fatty acid tails, where one tail is unsaturated (meaning it has a double bond between carbons, leading to a kinked shape).

Final answer:

Phospholipids are amphipathic molecules consisting of a hydrophilic (water-attracting) head group that contains a phosphate and is attached to a glycerol molecule and a hydrophobic (water-repelling) tail that contains two fatty acid chains. This structure permits different interactions based on charge and is crucial in forming biological membranes.

Explanation:

A phospholipid is an amphipathic molecule, or a molecule with both hydrophilic and hydrophobic components. This structure consists of a hydrophilic phosphatase-containing group (the head), and two hydrophobic fatty acid chains (the tails). The hydrophilic head group is typically made up of a phosphate group attached to a glycerol molecule. The hydrophobic tails are generally long hydrocarbon chains comprising of either saturated or unsaturated fatty acids.

This pattern allows for the dual-loving character of the phospholipid to interact differently with substances based on their charges and allows phospholipids to play a crucial role in the formation of biological membranes such as the plasma membrane.