Question

If 7.582 x 1028 molecules are present of KCl, how many grams of KCl do you
have? (Show work) HELLPPPPP

Answer 1

Answer:

Mass of KCL = 9.4 x 10^6 grams

Explanation:

To convert known number of molecules of any substance into its number of moles, we would be needing first the number of moles of that substance.

According to Avagadro, one mole of any substance has 6.023 x 10^23 molecules in it.

No of moles of KCL = Molecules of KCL / Avagadro number

No of moles of KCL = 7.582 x 10^28 / 6.023 x 10^23

No of moles of KCL = 1.26 x 10^5

Now molar mass of KCL = 74.5 g/mol

Mass of KCL = 74.5 x 1.26 x 10^5

Mass of KCL = 9.4 x 10^6 grams

Answer 2

Given:

No of KCl molecules = 7.582 x 10²⁸

To Find:

The amount of KCl in grams in the given no of molecules.

Calculation:

- No of moles of KCl = 7.582 x 10²⁸ / 6.022 x 10²³

⇒ No of moles of KCL = 1.259 x 10⁵

- Mass of KCl = No of moles x Molar mass

⇒ Mass of KCl = 1.26 x 10⁵ x 74.5

⇒ Mass of KCl = 93.79 x 10⁵ gm = 9.379 x 10⁶ gm

- So, we have 9.379 x 10⁶ gm of KCl.