Question

How many moles are in .5g of sodium bromide?

Answer 1

To determine the number of moles in 0.5g of sodium bromide, calculate the molar mass of NaBr, which is 102.89 g/mol, and then use the formula to find the moles which amounts to 0.00486 moles.

Step-by-step explanation:

To find out how many moles of sodium bromide are in 0.5 grams, you would use the formula:

1. Find the molar mass of sodium bromide (NaBr). Sodium (Na) has an atomic mass of approximately 22.99 g/mol, and bromine (Br) has an atomic mass of approximately 79.90 g/mol. Adding these together, the molar mass of NaBr is approximately 22.99 g/mol + 79.90 g/mol = 102.89 g/mol.
2. Use the formula moles = mass (g) ÷ molar mass (g/mol) to calculate the number of moles. In this case, it would be 0.5 g ÷ 102.89 g/mol.
3. Calculate the result, which would be 0.00486 moles of sodium bromide.

This method can be applied similarly to determine moles in other substances by substituting the appropriate molar masses.

Answer 2

Answer: 4.86 x 10⁻³ mole.

Step-by-step explanation:

• The number of moles can be calculated using the relation; n = mass / molar mass.

• n is the number of moles, mass is the mass of the substance in g (m = 0.5 g), and molar mass of NaBr = 102.894 g/mole.

• n = mass / molar mass = (0.5 g) / (102.894 g/mole) = 4.86 x 10⁻³ mole.