Final answer:
To find the number of moles in 20g of Cu(NO3)2, we calculate the molar mass of Cu(NO3)2 to be 187.57 g/mol and then use the formula: number of moles = mass / molar mass. The result is approximately 0.107 moles of Cu(NO3)2.
Step-by-step explanation:
To calculate the number of moles in 20g of Cu(NO3)2, we need to first determine the molar mass of copper(II) nitrate. The molar mass of copper(II) nitrate can be calculated by adding the atomic masses of its constituent atoms: 1 mole of copper (Cu), 2 moles of nitrogen (N), and 6 moles of oxygen (O).
The atomic mass of Cu is approximately 63.55 g/mol, that of N is 14.01 g/mol, and that of O is 16.00 g/mol. Therefore, the molar mass of Cu(NO3)2 is:
63.55 g/mol (for Cu) + 2 * 14.01 g/mol (for N) + 6 * 16.00 g/mol (for O) = 187.57 g/mol.
Now, to find the number of moles of Cu(NO3)2 in 20 g:
Number of moles = mass (g) / molar mass (g/mol) = 20 g / 187.57 g/mol ≈ 0.107 moles of Cu(NO3)2.
The number of moles in 20g of Cu(NO3)2 can be calculated using the molar mass of Cu(NO3)2. The molar mass of Cu(NO3)2 is approximately 187.5 g/mol.
To calculate the number of moles, we divide the mass of Cu(NO3)2 by its molar mass:
Moles = Mass / Molar mass
Substituting the values, we get:
Moles = 20g / 187.5 g/mol = 0.107 moles
Therefore, there are approximately 0.107 moles in 20g of Cu(NO3)2.