Question

what is the mass of 4.0 moles of sodium, na?
? g na
remember, 1 mole = molar mass
report your answer using correct significant figures.

Explanation:

Step1: Find molar mass of Na

The molar mass of sodium (Na) is approximately 22.99 g/mol (from periodic table).

Step2: Calculate mass using moles

Use the formula \( \text{Mass} = \text{Moles} \times \text{Molar Mass} \). Given moles = 4.0 mol, molar mass = 22.99 g/mol. So, \( \text{Mass} = 4.0 \, \text{mol} \times 22.99 \, \text{g/mol} \).
Calculate the product: \( 4.0 \times 22.99 = 91.96 \), and with significant figures (4.0 has two significant figures), we round to 92 g (or more precisely, considering 22.99 is ~23, 4.0×23 = 92).

Answer:

92 (or 91.96 depending on precision, but with significant figures from 4.0, 92 g)