Question

To gain an idea as to how many atoms are in a gram or so of copper, use the larger balance
on the right. Press Add atoms to put a scoop of atoms in the weighing dish, and keep
adding until the balance registers between 1 and 2 grams. If you don't seem to be making
much progress, adjust the exponent using the slider, which will make the scoop size bigger.
How many atoms did you need to add?

Answer 1

Answer:

Explanation:

To solve this problem, we must understand the relationship between mass of a substance and the number of atoms.

Atoms are the smallest indivisible particles of any matter. A substance can be made up of several number of atoms in their space.

The mass of any substance is a function of the amount of atoms its contains.

The mass of a substance is related in chemistry to the amount of atoms its contains using the parameter called the number of moles.

A mole is the amount of substance that contains the Avogadro's number of particles. This number is 6.02  x 10²³ particles. The particles here can be protons, neutrons, electrons, atoms e.t.c.

Now,

             Number of moles  = $\frac{mass}{molar mass}$

          Molar mass of copper  = 63.6g/mole

         Number of moles  = $\frac{2}{63.6}$  = 0.03mole

Since 1 mole of a substance contains  6.02  x 10²³atoms

        0.03 mole of copper will contain 0.03 x  6.02  x 10²³atoms

                                                    = 1.89 x 10²² atoms

He needs to add 1.89 x 10²² atoms to make 2g of the sample.

Answer 2

Mole is unit that is used to measure the smaller particles such as ions, atoms and molecules.   There are $\bold {1.89 x 10^2^2 }$ atoms are present in the 2 g of Copper.

Mole:

Mole is unit that is used to measure the smaller particles such as ions, atoms and molecules.  One mole is equal to the Avogadro's constant.

• One moles of atoms are present in the 12 g of C-12.

• 1 mole = $\bold {6.02 x 10^2^3}$ molecules

The formula foe number of mole,

$\bold {n = \dfrac {w}{m}}$

Where,

n - number of moles = 0.03 mole

w - mass of molecule

m - molar mass of the copper = 63.54 g/mol

The number of atoms in the 0.03 moles.

$\bold {\bold =0.03 \times {6.02 x 10^2^3} }\\\\\bold {= 1.89 x 10^2^2 }$

Therefore, there are $\bold {1.89 x 10^2^2 }$ atoms are present in the 2 g of Copper.

To know more about moles, refer to the link:

https://brainly.com/question/20290065