What is the mass of a sample of nh3 containing 3,80 x 10^24 molecules of nh3?
748 grams
894 grams
101 grams
107 grams

107 grams

Explanation:

1 mole of any substance contains 6.022*10²³ molecules/ions/atoms.

1 mole of contains 6.022*10²³ molecules of .

Since molar mass of   is 17 grams,

17 g of NH3 contains 6.022*10²³ molecules of .

We have to find the mass of NH3 when it contains molecules.

By unitary method, it is .

Hence 107 grams of contains molecules of .

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.