College

How many grams are in [tex]7.00 \times 10^{22}[/tex] molecules of NaOH?

A. 46.5
B. 6.65
C. 7.0
D. 4.65
E. 11.6

Answer :

Answer:

[tex] \huge{ \boxed{4.64 \: g}}[/tex]

Explanation:

The number of grams of NaOH can be found by using the formula;

mass = number of moles × molar mass

Molar mass of NaOH = 40 g/mol

Since the number of particles was given the number of moles of the compound can be found by using the formula;

[tex] n = \dfrac{N}{L} [/tex]

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question;

N = 7.00 × 10²² molecules

[tex] \therefore \: n = \dfrac{7.00 \times {10}^{22} }{6.02 \times {10}^{23} } \\ = 0.116 \: moles[/tex]

The number of moles attained is then substituted into the formula for finding the mass of the compound.

[tex] \therefore \: mass = 0.116 \times 40 = 4.64 \: g[/tex]