All categories

3 years ago

What is the total number of molecules of hydrogen in 0.75 mole of hydrogen?

Chemistry

1 answer:

Phoenix [80]3 years ago

8 0

Answer:

Explanation:

Avogadro's number, 6.022 * 1023 is the number of things in one mole. The question indicates that there is 1 mole of H2. Thus there are 6.022 * 1023 molecules of H2

You might be interested in

What are the disadvantages of aluminium fir building cars

Wittaler [7]

Disadvantages of aluminum in building cars include:

On average, aluminum is more expensive than steel, as much as two to three times.

Aluminum is not easily welded. If a steel door or panel suffers a crack, often it cam be welded back together easily, primed and repainted so its difficult to tell any body work has been performed. This cannot be done with aluminum. Steel also can be bent and shaped as needed.

Body shops and even dealer service centers are currently equipped for steel work with technicians skilled in the art of welding and steel fabrication. The cost of switching over to an infra structure designed specifically for all-aluminum vehicles or mass production of aluminum vehicles and components would be high.

4 0

3 years ago

PLEASE HELPPP!!!!!!!!!!!!!!!!!!!!

riadik2000 [5.3K]

Similarities. very useful
differences. coal is a pullutant. while womd is not. i guess

6 0

3 years ago

Read 2 more answers

Which of the following is a true statement about odors?

Novay_Z [31]

Pretty sure its all of the above since all of them are true

5 0

3 years ago

If an isotope of uranium, uranium-235, has 92 protons, how many protons does the isotope uranium-28 have?

padilas [110]

92. A<span>ll </span>isotopes<span> of uranium have the same number of protons</span>

4 0

3 years ago

What is the kinetic energy of the emitted electrons when cesium is exposed to UV rays of frequency 1.0×1015Hz?

RideAnS [48]

The kinetic energy of the emitted electrons of cesium when it is exposed to UV rays of frequency $1.0 \times {10^{15}}\;{\text{Hz}}$ is $\boxed{6.63 \times {{10}^{ - 19}}\;{\text{J}}}$

Further Explanation:

Photoelectric effect:

When light is made to fall on any substance, electrons are emitted from it. This is known as the photoelectric effect and the emitted electrons are called photoelectrons. The electrons are emitted because of the transference of energy from light to the electrons.

Cesium is a member of the alkali metal group so it is highly reactive and shows photoelectric effect to the maximum extent. It can remove its electron so easily because of its atomic size. Due to large atomic size of cesium, its outermost electrons are held very less tightly to the nucleus and therefore removed easily.

According to the Planck-Einstein equation, the energy is proportional to the frequency and is expressed as follows:

${\mathbf{E=h\nu }}$ ......(1)

Here,

${\text{E}}$ is the energy.

$h$ is the Plank’s constant.

$\nu$ is the frequency.

The frequency of UV rays is $1.0 \times {10^{15}}\;{\text{Hz}}$ or $1.0 \times {10^{15}}\;{{\text{s}}^{ - 1}}$

The value of Planck’s constant is $6.626 \times {10^{ - 34}}\;{\text{J}}\cdot{\text{s}}$ .

Substitute these values in equation (1)

$\begin{aligned}{\text{E}}&=\left( {6.626 \times {{10}^{ - 34}}\;{\text{J}}\cdot{\text{s}}}\right)\left( {1.0 \times {{10}^{15}}\;{{\text{s}}^{ - 1}}}\right)\\&=6.63\times {10^{ - 19}}\;{\text{J}}\\\end{aligned}$

But when electrons are ejected out from the surface of the substance, all of its energy is considered as kinetic energy.

So the kinetic energy of the electrons is ${\mathbf{6}}{\mathbf{.63 \times 1}}{{\mathbf{0}}^{{\mathbf{ - 19}}}}\;{\mathbf{J}}$ .

Learn more:

1. Statement about subatomic particle: brainly.com/question/3176193

2. The energy of a photon in light: brainly.com/question/7590814

Answer details:

Grade: Senior School

Subject: Chemistry

Chapter: Structure of the atom

Keywords: kinetic energy, frequency, energy, photoelectric effect, Planck's constant, light, electrons, photoelectrons, proportional, transference, reactive, cesium.

7 0

3 years ago

Read 2 more answers