What is the mass of #9.25 times 10^22# molecules of water?
A mole of any compound has a mass equal to the compound's relative formula mass in grams.
So, the first step is to work out how many moles of the substance there is.
So we have 1.54 moles of water.
Next, we need to find the relative formula mass of water using the relative atomic masses of the atoms making it up. Water is
Now we remember the rule about moles and multiply 18 by our 1.54 moles to get 27.72g (27.7 to 3SF)
Hope this helps; let me know if I can do anything else:)
The relationship between the number of particles and the number of mole of a substance is given by the equation
Let's substitute the definition of
Then, let's substitute the value of
Now, let's evaluate the molar mass of water:
Substituting into the equation:
Dividing both sides of the equation by
Multiplying both sides by
Therefore, the mass of