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2 years ago

How could you engineer a device that produces beneficial friction and heat?

Chemistry

1 answer:

nlexa [21]2 years ago

3 0

Answer:

Explanation:

That's why rubbing your hands together makes them warmer. ... Friction causes the molecules on rubbing surfaces to move faster, so they have more energy. This gives them a higher temperature, and they feel warmer. Heat from friction can be useful.

You might be interested in

Which indicator is yellow in a solution with a pH of 9.8?

Vlada [557]

It's the Methyl Orange.
at about 4.4 pH, it changes from red to Yellow, to indicate an acid solution.
This pH indicator is normally used in titration of acids.

Hope this Helps :)

8 0

3 years ago

Read 2 more answers

Lithium has two stable isotopes with masses of 6.01512 amu and 7.01600 amu. The average molar mass of Li is 6.941 amu. What is t

Dvinal [7]

Answer : The percent abundance of Li isotope-1 and Li isotope-2 is, 6.94 % and 93.1 % respectively.

Explanation :

Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.

Formula used to calculate average atomic mass follows:

$\text{Average atomic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i$ .....(1)

Let the fractional abundance of Li isotope-1 be 'x' and the fractional abundance of Li isotope-2 will be '100-x'

For Li isotope-1 :

Mass of Li isotope-1 = 6.01512 amu

Fractional abundance of Li isotope-1 = x

For Li isotope-2 :

Mass of Li isotope-2 = 7.01600 amu

Fractional abundance of Li isotope-2 = 100-x

Average atomic mass of Li = 6.941 amu

Putting values in equation 1, we get:

$6.941=[(6.01512\times x)+(7.01600\times (100-x))]$

By solving the term 'x', we get:

$x=694.048$

Percent abundance of Li isotope-1 = $\frac{694.048}{100}=6.94\%$

Percent abundance of Li isotope-2 = 100 - x = 100-6.94 = 93.1 %

6 0

2 years ago

The final charge on each of the three separated spheres in part (b) is +3.0 μC. How many electrons would have to be added to one

marishachu [46]

Answer:

$1.873\times 10^{13}$ electrons should be added to one of these spheres to make it electrically neutral.

Explanation:

Total charge on each sphere = +3.0 μC = $3\times 10^{-6} C$

$1 \mu C=10^{-6} C$

In order to neutralize the positive charge equal magnitude of negative charge is to be added.

Total charge electrons, Q= -3.0 μC = $-3\times 10^{-6} C$

Number of electrons = n

Charge on a single electron, e = $-1.602\times 10^{-19} C$

Q = n × e

$-3\times 10^{-6} C=n\times (-1.602\times 10^{-19} C)$

$n=\frac{-3\times 10^{-6} C}{-1.602\times 10^{-19} C}=1.873\times 10^{13}$

$1.873\times 10^{13}$ electrons should be added to one of these spheres to make it electrically neutral.

4 0

3 years ago

1. How many ATOMS of boron are present in 2.20 moles of boron trifluoride ? atoms of boron.

maks197457 [2]

Answer:

1. How many ATOMS of boron are present in 2.20 moles of boron trifluoride? atoms of boron.

2. How many MOLES of fluorine are present in of boron trifluoride? moles of fluorine.

Explanation:

The molecular formula of boron trifluoride is $BF_3$ .

So, one mole of boron trifluoride has one mole of boron atoms.

1. The number of boron atoms in 2.20 moles of boron trifluoride is 2.20 moles.

The number of atoms in 2.20 moles of boron is:

One mole of boron has ---- $6.023x10^2^3$ atoms.

Then, 2.20 moles of boron has

- $=2.20 mol. x 6.023 x 10^2^3 atoms /1 mol\\=13.25x10^2^3 atoms$

2. Calculate the number of moles of BF3 in 5.35*1022 molecules.

$(5.35x10^2^2 molecules/6.023x10^2^3)x 1mol\\=0.0888mol$

One mole of boron trifluoride has three moles of fluorine atoms.

Hence, 0.0888moles of BF3 has 3x0.0888mol of fluorine atoms.

=0.266mol of fluorine atoms.

5 0

2 years ago

Sort these isotopes by whether they are most likely to undergo fusion or fission.

Maslowich

Answer:

Uranium-233- fission

Plutonium-239- fission

Plutonium-241- fission

Hydrogen-3 fusion

Hydrogen-1 fusion

Helium-3 fusion

Explanation:

In nuclear fission, heavy nuclear disintegrate into smaller nuclei when bombarded with particles such as neutrons. Fission reaction is common among nuclei having a high atomic number such as plutonium and uranium.

Fusion occurs between two light nuclei such as hydrogen or helium. It involves the combination of two lighter elements to give a heavier element with the release of tremendous amount of energy.

4 0

2 years ago