The mass of glucose that contains a million oxygen atoms and round it to 2 significant digits

Answer 1

Hi Shougy D.,

How you should proceed:

Start with what you are given (1*10^6 oxygen atoms)= G. Write the formula of glucose (you should memorize a few things in science, and the formula for chemical ions and for simple sugars are among them!) -- if you need to look it up, do so.

Reason as follows: since there are P atoms of oxygen in each molecule of glucose, therefore I am dealing with (G/P ) molecules of glucose.

Next, I convert to moles of glucose, just divide by N (Avogadro's Number).

Now, what is the molar mass of glucose (also called formula weight)=F ? Either look it up, or add it up from the periodic table and the masses of each atom in it (don't forget to include the multiples of each as per the formula!). This has units of grams/mole of glucose.

So if you take ((G/P)/N)*F , that will have units of grams (of glucose). You will need to use scientific notation, and round to 2 significant digits as requested.

-- Cheers, --Mr. d.

P.S. You should review the logical steps in the calculation above, so that you absolutely know immediately how to run from one step to another, both forwards and backwards. This is essential thinking for chemistry.

-- Cheers, --Mr. d.