Take 82 grams and divide it by the gfm of water which is 18 g/mole...(82g)/(18.0g/mole)=4.555 -> the answer is 4.6 moles
44.99g H2O x (1 mol H2O / 18.02g H2O) x (6.022x10^23 molecules H2O / 1 mol H2O) = 1.503x10^24 molecules H2O
Lead is a basic metal and almost 11 isotopes of Lead are reported. The isotopes with greater natural abundance are as follow;
1) ²⁰⁸Pb with abundance 52.4 %
2) ²⁰⁶Pb with abundance 24.1 %
3) ²⁰⁷Pb with abundance 22.1 %
4) ²⁰⁴Pb with abundance 1.4 %
Molar mass of ²⁰⁸Pb:
Molar mass of any element is the total of number of protons, neutrons and electrons.
As, number of protons in Lead are 82 then in ²⁰⁸Pb isotope number of neutrons are...
# of Neutrons = M.mass - # of protons
# of Neutrons = 208 - 82
# of Neutrons = 126
Result:
Molecular Mass of Lead (²⁰⁸Pb) is 208 amu.
# of Protons in ²⁰⁸Pb = 82
# of Neutrons in ²⁰⁸Pb = 126
4, 3, 1
Explanation:
Sb has four on the right, so it needs four on the left. It's all alone, so <u>4</u>.
O2 comes in pairs, so you only need <u>3</u> of those to get six oxygens.
And 1 is the place holder for the right side since we got the left to match perfectly.
The difference between a substance and a mixture is that a substance is one of a kind, a material of the same composition throughout, on the contrary, a mixture is one or more different substances brought together and mixed together without changing the nature of each single substance.
One way to test it is to take two substances like sand and table salt. They should each be in granular form and in adequate amount to mix. Neither substance has changed after mixing the two. Even though it may not be easy or convenient to accomplish, each substance could be separated out from the mixture.
When it comes to two substances in lump form, it would not be a mixture when one lump is positioned next to the other lump because there are not enough pieces to combine.
However, there could be a mixture of three substances, like sand, table salt and graphite powder and there could be a mixture with four substances, etc., ad infinitum.
Mixtures are of solid substances in general. On the other hand, one starts referring to solutions when liquids are involved. Gases can be a mixture like for example, air is a mixture with nitrogen, oxygen, argon, etc.
