Chemistry Help!?

Question

I have no clue what this is or how to do it! i`ve went to a zillion websites and i don`t understand any of it!

1. the atomic mass of Mo is 95.94. calculate the a)mass is grams of one Mo atom. b)number of atoms in one fram of Mo.

2.Determine the mass of 2.00x10^15 Ag atoms.

3.239 g of C5H10O5 would be how many a)moles of C5H10O5 b)C5H10O5 molecules c)moles of carbon d)hydrogen atoms e)protons

Answer 1

Okay- it's been a long time but
1. a) Take 95.94 grams per mole/6.02X10^23 atoms/mole when you invert and multiply the units you will see that moles cross out and you have grams per atom - it will be a small number. b) one gram of Mo is 1gram/95.94 grams per mole so take that answer times 6.02X10^23 atoms per mole.
2. Take 2.00X10^15 atoms/6.02X10^23 atoms per mole and you will get the number of moles of Ag (silver). Take the number od moles times silver's atomic mass and you have the answer.
3. First you have to determine how much C2H10O5 (Sugar I think) has for a mass for one mole (2 X 12 for carbon + 10*1 for hydrogen + 5 X16 for oxygen - or 114 grams/mole). a)take 3.239 grams/114 grams/mole and that gives you moles. b) take the moles you found in a) times 6.02X10^23 atoms/mole and that gives you atoms in 3.239 grams c) you have 5 times as many moles of carbon as you do of the compound - take a) times 5. d) To find hydrogen atoms take the moles in a) times 10 (there are 10 hydrogens for every one molecule of this compound) times 6.02X10^23 atoms per mole. e) Take the (atomic number of carbon X5 +the atomic number of H X10 + atomic number of oxygen X5) X the number of moles you found in a) above. Hope this helps - like I said it's been about 20 years since I did this stuff.

Answer 2

I believe this is a measure question of atomic weight , that means it
is theoretic to some point. An atom is by general definition liter, smaller
and totally invisible. This last part is the clue, invisible means you cannot
weigh, so then only a protracting atomic weight machine can hold it on a
scale. That is the second clue the number of grams in the second part is
another gem, that is the size of a miniature crystal, say sugar or salt. This
question tells you that the weight of a crystal can be different proportions
so to say that is depends on what you assign it, for function values. A
mole is described as atoms totalling a mole in values. If the weight is
in atoms is must be shown on a graph.

Answer 3

1) the definition of a mole is two fold -
a) It is 6.02 x10^23 atoms
b) 1 mole of any element weighs the atomic mass in grams - that is 1 mole of oxygen weighs 16 (15.9994 I think). 1 mole of Mo weighs 95.94 grams

2) looking at the above definition
6.02 x10^23 / 2.00^15 = number of moles of gold
number of moles of gold x atomic weight of gold = answer

3 total atomic weight of C5H10O5 (should be about 150)
1 mole would be 150 grams

a) so 3.239 g is about 0.03 moles
b) definition 6.02x10^23 * moles = molecules
c)5 carbon atoms / molecule so multplication
d)10 H atoms / molecule so multiplication
e) use periodic table to total protons in 1 molecule, then multiply by number of molecules


I hope I helped enough without too much help