The diameter of a carbon atom is 1.54 å. (a) express this diameter in picometers. (b) how many carbon atoms could be aligned side by side in a straight line across the width of a pencil line that is 0.20 mm wide

In a 0.2 mm width, 1.3 x 10⁶ carbon atoms could be aligned side by side in a straight line. The diameter of a carbon atom is 1.54 x 10² pm

An angstrom is a unit of measurement of the length which is equal to the .

1 = 10² pm

Thus,

Diameter of a carbon atom = 1.54   = 1.54 x 10² pm

B)

Since, 1 mm =  10⁹ pm

Thus,

Total distance = 0.2 mm = 0.2 x 10⁹ pm

So,

Therefore,  In a 0.2 mm width, 1.3 x 10⁶ carbon atoms could be aligned side by side in a straight line.

Learn more about  Angstrom (Å):

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(a) 1.54 x 10² pm

(b) 1.3 x 10⁶ is the number of carbon atoms could be aligned side by side in a straight line across the width of 0.2 mm.

Explanation: -

1 å = 10² pm

Diameter of a carbon atom = 1.54 å = 1.54 x 10² pm

1 mm = 10⁹ pm

Total distance = 0.2 mm = 0.2 x 10⁹ pm

Number of carbon atoms could be aligned side by side in a straight line across the width = Total distance / Diameter of a carbon atom

=

= 1.3 x 10⁶

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.