Question

How many formula units (particles of AgNO3) are in 5.50

Answer 1

Answer:

• 2.0 X 10²² molecules of AgNO₃

Explanation:

Given 5.50 grams of AgNO₃, how many formula units of AgNO₃ are contained in the 5.50 grams of AgNO₃? (formula wt. of AgNO₃ = 169,87 g/mole).

Solution:

• 1st convert grams to moles => moles AgNO₃ = 5.50 g AgNO₃ / 169.841g AgNO₃ = 0.032377 mole AgNO₃
• 2nd calculate number of particles in 0.032377 mole AgNO₃ .      Number AgNO₃ molecules in 0.032377 mole AgNO₃ = 0.032377 mole AgNO₃ X 6.023 x 10²³ molecules of AgNO₃ /1.0 mole AgNO₃ =  1.95007 X 10²² molecules of AgNO₃ in 5.50 grams of AgNO₃.
• The appropriate form of the answer should contain 2 Sig,Figs. based on the data point having the least number of sig.figs. in the given data. This then is 5.50 grams of AgNO₃ which has 2 sig.figs.
• Therefore, the number of AgNO₃ molecules in 5.5 grams of AgNO₃ = 2.0 X 10²² molecules of AgNO₃. (Note: 1.95 rounds to 2.0).