Question

на деталь,площадь поверхности которой 20 см2,нанесен слой серебра толщиной 1мкм.сколько атомов серебра содержится в этом слое

Answer 1

Дано: серебро - Ag

S=20 см²

t=1 мкм=1*10⁻⁴ см.

M=108 г/моль (молярная масса из таблицы Менделеева)

Nа=6,022*10²³ моль⁻¹ (постоянная Авогадро)

Найти: N

Решение:

1) Найдем объем слоя: V(Ag)=S*t=20*0.0004=0.008 см³

2) Зная, что плотность сербра p(Ag)=10,5 г/см³, найдем его массу:

m(Ag)=V*p=0,008*10,5=0,084 г.

3) Определим количество вещества:

n(Ag)=m*M=0.084*108=9,072 моль.

4) Число атомов составит:

N=n*Nа=9,072*6,022*10²³=54,6*10²³=5,5*10²⁴ атомов.

Ответ: N=5,5*10²⁴ атомов.

Answer 2

Calculation of the Number of Silver Atoms in a 1μm Thick Layer

To calculate the number of silver atoms in a 1μm thick layer with a surface area of 20 cm², we need to consider the density of silver and Avogadro's number.

1. Calculate the volume of the layer: - The thickness of the layer is given as 1μm. - The surface area of the layer is given as 20 cm². - Convert the thickness to cm: 1μm = 0.0001 cm. - Multiply the thickness by the surface area to get the volume: 0.0001 cm * 20 cm² = 0.002 cm³.

2. Calculate the mass of the silver in the layer: - The density of silver is approximately 10.5 g/cm³. - Multiply the volume by the density to get the mass: 0.002 cm³ * 10.5 g/cm³ = 0.021 g.

3. Calculate the number of moles of silver: - The molar mass of silver is approximately 107.87 g/mol. - Divide the mass by the molar mass to get the number of moles: 0.021 g / 107.87 g/mol = 0.000194 moles.

4. Calculate the number of atoms of silver: - Avogadro's number is approximately 6.022 x 10^23 atoms/mol. - Multiply the number of moles by Avogadro's number to get the number of atoms: 0.000194 moles * 6.022 x 10^23 atoms/mol = 1.167 x 10^20 atoms.

Therefore, there are approximately 1.167 x 10^20 atoms of silver in the 1μm thick layer with a surface area of 20 cm².

Please note that the values used in this calculation are approximate and may vary slightly depending on the specific properties of the silver used.