This is tricky because, believe it or not, there are potentially as many atoms in a grain of sand as their are stars in the entire universe. But, here goes.
Sand is made up of Silica, which has the formula SiO2
silicon weighs 28 atomic units
Oxygen weighs 16 atomic units
so each SiO2 weighs 60 atomic units
There are 6.023 x 1023 atomic units in a gram. that is 6 with 23 zeros after it.
So there would be 6.023 x 1023 / 60 = 1x 1022 SiO2s in a gram, so 3 x 1022 atoms in a gram.
Say a grain of sand is 1mm across it has a volume of 0.001cm3;1cm3 of sand weighs about 2.6g, so a grain of sand will weigh 0.0026g.
So, to find the number of atoms in a grain of sand we multiply the number of atoms per gram by the number of grams:
3 x 1022 x 0.0026g = 7.8 x 1019 atoms
or
78,000,000,000,000,000,000.
Assuming you could count 2 atoms per second, it would take approximately 1,236,681,887,366 (1.2 Trillion) years.
Yes, really. If I were you I would try counting at least four every second, then it would only take 6.2 billion. You'd have a lot more free time.
3
A very rough approximation would be in the order of 1023 atoms, ie a 1 followed by 23 zeros, which is a very big number. Given that there are over 10^21 atoms in a large grain of sand, weighing 0.03g there will be a lot more (maybe x10 or x100) in a grain of rice (which is much larger than a grain of sand). Note that rice is organic so will have a lot of hydrogen atoms as well as carbon, oxygen, nitrogen, and many others in lesser degree. The previously stated answer of "30,000 atoms in one grain of rice" is absurd. Either the poster is testing how long it takes for an incorrect answer to be fixed or is quite ignorant of atomic dimensions (or both!).
It would depend on the type of atom. Atoms of different elements come in different sizes. We can take an average of about 1 angstrom, that is 10^-10 meters or 10^-8 cm. Using that average you would need 10^8 atoms.
Element
Assuming a grain of salt is sodium chloride (table salt) with a density of 2.16 g/cm^3, the volume of a grain of salt is 0.3 mg / 2.16 g/cm^3 = 0.139 mm^3. The volume of one unit cell of NaCl is 0.052 nm^3. Dividing the volume of the grain of salt by the volume of one unit cell gives approximately 2680 unit cells.
If you count one rice grain per second, it will take 6.022e23 seconds to count 1 mole of rice. 1 year is 31556926 seconds, so it will take 1.9e16 years to count 1 mole of rice.
It would take a prohibitively long time. A "googol" is 10100 (a very large number). There are only about 1080 atoms in the observable universe.
Time taken would depend on the size of the paper and the sophistication of the measuring device ... mainly the rate of counting of which it's capable.
That depends on whether you're using the "long count" or the "short count". In the short count, it would be 18. In the long count, it would be 24.
That depends on how fast you can count.
It would take nothing
599,999 days.
Long grain, short grain & short grain.
Count the atoms in each substance in the reactants and products. (Apex)
A single grain of long grain rice typically weighs about 0.02 grams.
If you could count 1 atom per second, it would take you 6.02 x 10^23 seconds to count the atoms in 12.0 g of carbon. Since there are 60 seconds in a minute, 60 minutes in an hour and 24 hours in a day and approximately 365 days in a year, this is equivalent to (6.02 x 10^23)/(60 x 60 x 24 x 365) = approximately 19 billion years.
Rice, brown, long grain, cooked-10mg Rice, white, long grain, par-boiled-5mg Rice, white, long grain, dry-9mg Rice, white, long grain, instant-5mg Rice, white, long grain, regular, cooked-2mg