b) Find the mass of 6.42 × 1024 formula units
of NaBF4 (sodium tetrafluroborate).
Answer in units of g.
To find the mass of 6.42 x 10^24 formula units of NaBF4, we need to calculate the molar mass of NaBF4 first.
The molar mass of NaBF4 can be calculated by adding the atomic masses of each element in one molecule of NaBF4.
The atomic mass of sodium (Na) is 22.99 g/mol.
The atomic mass of boron (B) is 10.81 g/mol.
The atomic mass of fluorine (F) is 18.99 g/mol.
Since there are 4 fluorine atoms in NaBF4, we multiply the atomic mass of fluorine by 4.
The molar mass of NaBF4 is:
(1 x atomic mass of Na) + (1 x atomic mass of B) + (4 x atomic mass of F)
= (1 x 22.99 g/mol) + (1 x 10.81 g/mol) + (4 x 18.99 g/mol)
= 22.99 g/mol + 10.81 g/mol + 75.96 g/mol
= 109.76 g/mol
Now, we can calculate the mass of 6.42 x 10^24 formula units of NaBF4.
Mass (g) = number of formula units x molar mass
= 6.42 x 10^24 x 109.76 g/mol
Using scientific notation, we can calculate:
Mass (g) = 6.42 x 10^24 x 109.76
= 7.044192 x 10^26 g
Therefore, the mass of 6.42 x 10^24 formula units of NaBF4 is 7.044192 x 10^26 grams or approximately 7.04 x 10^26 grams.
To find the mass of 6.42 × 10^24 formula units of NaBF4, we need to know the molar mass of NaBF4.
The molar mass of NaBF4 can be calculated by adding up the atomic masses of each element in the formula:
- One sodium atom (Na) has a molar mass of 22.99 g/mol.
- One boron atom (B) has a molar mass of 10.81 g/mol.
- Four fluorine atoms (F) have a molar mass of 18.99 g/mol each.
So, the molar mass of NaBF4 is:
Molar mass of NaBF4 = (1 * molar mass of Na) + (1 * molar mass of B) + (4 * molar mass of F)
= (1 * 22.99 g/mol) + (1 * 10.81 g/mol) + (4 * 18.99 g/mol)
= 22.99 g/mol + 10.81 g/mol + 75.96 g/mol
= 109.76 g/mol.
Now, to find the mass of 6.42 × 10^24 formula units of NaBF4, we can use the following steps:
Step 1: Calculate the number of moles.
Number of moles = number of formula units / Avogadro's number
= (6.42 × 10^24 formula units) / (6.022 × 10^23 formula units/mol)
= 10.66 mol.
Step 2: Calculate the mass.
Mass = number of moles * molar mass
= (10.66 mol) * (109.76 g/mol)
= 1170.18 g.
To find the mass of 6.42 × 10^24 formula units of NaBF4, we first need to determine the molar mass of NaBF4.
The molar mass is the sum of the atomic masses of all the atoms in a chemical formula. To find it, we need to know the atomic masses of sodium (Na), boron (B), and fluorine (F), and the number of atoms of each element in the formula.
Here are the atomic masses:
- Sodium (Na): 22.99 g/mol
- Boron (B): 10.81 g/mol
- Fluorine (F): 18.99 g/mol
The formula for sodium tetrafluroborate (NaBF4) indicates that there is one sodium atom (Na), one boron atom (B), and four fluorine atoms (F) in each formula unit.
Now, let's calculate the molar mass of NaBF4:
Molar mass of NaBF4 = (1 * Na atomic mass) + (1 * B atomic mass) + (4 * F atomic mass)
Molar mass of NaBF4 = (1 * 22.99 g/mol) + (1 * 10.81 g/mol) + (4 * 18.99 g/mol)
Molar mass of NaBF4 = 22.99 g/mol + 10.81 g/mol + 75.96 g/mol
Molar mass of NaBF4 = 109.76 g/mol
Now, we can use the concept of molar mass to convert the given formula units of NaBF4 into grams.
To convert formula units to grams, we will use the following conversion factor:
1 mole of NaBF4 = 109.76 g
So, to find the mass of 6.42 × 10^24 formula units of NaBF4, we will perform the following calculation:
Mass = (6.42 × 10^24 formula units) * (1 mole / 6.02 × 10^23 formula units) * (109.76 g / 1 mole)
Mass = (6.42 × 10^24) * (109.76 / 6.02 × 10^23) g
Performing the calculation, we get:
Mass = 1118.61 g
Therefore, the mass of 6.42 × 10^24 formula units of NaBF4 is 1118.61 grams.