how many moles of water (h₂o) are present in a beaker containing 45.9 g h₂o? give your answer to the correct…
how many moles of water (h₂o) are present in a beaker containing 45.9 g h₂o? give your answer to the correct number of significant figures. (molar mass of water = 18.02 g/mol)\n45.9 g h₂o = mol h₂o\ndone
Answer
Answer:
2.55 mol
Explanation:
Step1: Recall mole - mass formula
$n=\frac{m}{M}$ where $n$ is the number of moles, $m$ is the mass in grams, and $M$ is the molar mass in g/mol.
Step2: Substitute given values
$m = 45.9$ g, $M=18.02$ g/mol. So $n=\frac{45.9}{18.02}$
Step3: Calculate the number of moles
$n=\frac{45.9}{18.02}\approx2.55$ mol (rounded to three significant figures as 45.9 has three significant figures)