Question

How many grams of sucrose (c12h22o11) are in 1.55 l of 0.758 m sucrose solution? express your answer in grams to three significant figures?

Answer 1

The molecular formula of sucrose is - C₁₂H₂₂O₁₁
molecular mass of sucrose - 342 g/mol
molarity of sucrose solution is 0.758 M
In 1 L solution the number of sucrose moles are - 0.758 mol
Therefore in 1.55 L solution, sucrose moles are - 0.758 mol/L x 1.55 L
                                                                           = 1.17 mol
The mass of 1.17 mol of sucrose is - 1.17 mol x 342 g/mol = 4.00 x 10² g

Answer 2

Answer : The mass of sucrose are, 402 grams

Solution :

Molarity : It is defined as the number of moles of solute present in one liter of solution.

Formula used :

$M=\frac{w}{M\times V}$

where,

M = molarity of solution = 0.758 M = 0.758 mole/L

w = mass of solute (sucrose) = ?

M = molar mass of solute (sucrose) = 342 g/mole

V = volume of solution in liter = 1.55 L

Now put all the given values in the above formula, we get the mass of sucrose.

$0.758mole/L=\frac{w}{342g/mole\times 1.55L}$

$w=402g$

Therefore, the mass of sucrose are, 402 grams