A nickel has a mass of 5.000 grams and is composed of 25% nickel and 75% copper. What is the mass of copper in the nickel? How many moles of copper are in this nickel? How many copper atoms are in this nickel?
mass Cu = 5.000 x 0.75 = ??
moles Cu = mass Cu/molar mass Cu.
There are 6.022 x 10^23 Cu atoms in a mole of Cu atoms.
Well, isn't this a copper-ative question! Let's break it down:
First, we need to find the mass of copper in the nickel. Since the nickel is made up of 75% copper, we can calculate it as follows:
Mass of copper = 75% of 5.000 grams
= 0.75 * 5.000 grams
Now, let me whip out my calculator... *boop boop boop* ...and we get:
Mass of copper = 3.750 grams
Next, we want to find out how many moles of copper are in the nickel. To do that, we'll use the molar mass of copper, which is 63.55 grams/mol:
Moles of copper = Mass of copper / Molar mass of copper
= 3.750 grams / 63.55 grams/mol
After some funny math, we find:
Moles of copper ≈ 0.059 moles
Lastly, we want to determine the number of copper atoms in the nickel, but to do that we need the Avogadro's number, which is 6.022 x 10^23 atoms/mol:
Number of copper atoms = Moles of copper * Avogadro's number
≈ 0.059 moles * 6.022 x 10^23 atoms/mol
Drumroll, please...
Number of copper atoms ≈ 3.552 x 10^22 copper atoms
So, there you have it! The mass of copper in the nickel is 3.750 grams, there are approximately 0.059 moles of copper present, and around 3.552 x 10^22 copper atoms can be found within that jolly old nickel.
To calculate the mass of copper in the nickel, we need to know the total mass of the nickel and its composition.
Given:
Mass of the nickel = 5.000 grams
Composition: 25% nickel and 75% copper
Step 1: Calculate the mass of copper in the nickel.
The nickel is composed of 75% copper. So, the mass of copper can be calculated as:
Mass of copper = 75% of the total mass of the nickel
Mass of copper = 0.75 * 5.000 grams
Mass of copper = 3.75 grams
Therefore, the mass of copper in the nickel is 3.75 grams.
Step 2: Calculate the number of moles of copper.
To determine the number of moles of copper, we need to use the molar mass of copper which is 63.55 grams/mol.
Number of moles of copper = Mass of copper / Molar mass of copper
Number of moles of copper = 3.75 grams / 63.55 grams/mol
Using a calculator:
Number of moles of copper ≈ 0.059 moles (rounded to three decimal places)
Therefore, there are approximately 0.059 moles of copper in the nickel.
Step 3: Calculate the number of copper atoms.
To determine the number of copper atoms, we will use Avogadro's number, which is 6.022 × 10^23 atoms/mol.
Number of copper atoms = Number of moles of copper * Avogadro's number
Number of copper atoms = 0.059 moles * 6.022 × 10^23 atoms/mol
Using a calculator:
Number of copper atoms ≈ 3.547 × 10^22 atoms (rounded to three significant figures)
Therefore, there are approximately 3.547 × 10^22 copper atoms in the nickel.
To find the mass of copper in the nickel, first, we need to determine the mass of copper.
Given that the nickel is composed of 75% copper, we can calculate the mass of copper as follows:
Mass of copper = 75% x Mass of nickel
Given that the mass of the nickel is 5.000 grams, we can substitute this value into the equation:
Mass of copper = 75/100 x 5.000 grams
Mass of copper = 3.750 grams
Therefore, the mass of copper in the nickel is 3.750 grams.
To determine the number of moles of copper in the nickel, we need to convert the mass of copper into moles using the molar mass of copper.
The molar mass of copper (Cu) is approximately 63.55 grams/mol.
Number of moles of copper = Mass of copper / Molar mass of copper
Number of moles of copper = 3.750 grams / 63.55 grams/mol
Number of moles of copper ≈ 0.0590 moles
Therefore, there are approximately 0.0590 moles of copper in the nickel.
To find the number of copper atoms in the nickel, we can use Avogadro's number, which is approximately 6.022 x 10^23 atoms/mol.
Number of copper atoms = Number of moles of copper x Avogadro's number
Number of copper atoms = 0.0590 moles x 6.022 x 10^23 atoms/mol
Number of copper atoms ≈ 3.547 x 10^22 atoms
Therefore, there are approximately 3.547 x 10^22 copper atoms in the nickel.