CHEMISTRY

Asked by TaegonTo calculate moles we use the formula: Moles = Mass (g) / Mr. The mass has been given in the questions as 44g. The Mr of Carbon Dioxide is the sum of the atomic masses of the elements in the compound. The atomic mass of Carbon is 12 and the atomic mass of Oxygen is 16 therefore the molecular mass of carbon dioxide is: 12 + 16 + 16 = 44. We can then substitute the values into our equation at the start 44/44 = 1 so we have one mole of Carbon Dioxide. To find out how many molecules this is we multiply the number of moles by Avagadro's Constant which will tell us how many molecules we have present. Avagadro's constant is equal to 6.023 x 10^23 so we have 1 x (6.023 x 10^23) molecules present which is 6.023 x 10^23.

Using the formula number of moles = Mass/Mr 44/44=1 mole of CO2 present. (Mr of carbon dioxide is (2*16)+12=44 Now times by Abogadros constant: 1* 6.022*10^23=6.022*10^23 molecules of CO2 are present. Understanding the last step is critical. 1 mole, is simply a random number; just like Pi or e. That number is 6.022*10^23, also known as avogadros constant. What is special about this number is that; when this amount of molecules or atoms are present, the mass of that amount of molecules or atoms, will be equal to the Mr/At of that atom/molecules. Thus, if we have 1 mole of a molecule present, we have 6.022*10^23 of those molecules present. If we have 2 moles of a molecule present, we have 2*1.022*10^23 of that molecule present etc.

Yes, as Sarah said moles=mass/Mr, so there is only 1 mole of CO2 in 44g CO2. Now let's work out how many CO2 molecules are there. Mole is a unit for measuring a large number of very small entities, like atoms, molecules, ions, etc. And 1 mole of substance is equal to 6.02214076 × 10^23. So if there is 1 mole of CO2, that means we have 6.02214076 × 10^23 CO2 molecules of CO2 in 1 mole of CO2. I hope that's helpful

Assuming you mean moles rather than miles To calculate moles we use the equation moles=mass/Mr We have been given the mass in the question, and we can calculate the Mr from the molecule formula of CO2. The atomic mass of carbon is 12 and for oxygen is it 16. Therefore, the Mr of CO2 is 12+16*2=44 Going back to our equation, we can now see that we have everything to calculate the moles. Therefore, substituting in the numbers we now have gives us 44/44. This = 1, and so we can see that we have one mole of CO2 in 44g

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