Answer:
You can model a substance doing a Lewis structure
And also you can model it doing a bond-line structure.
Question One
It's more a question of unscrambling what is there. The answer is correct.
If you look at your periodic table, there is such an element as Na which I suspect might be the problem.
It has an atomic mass of 23. It's atomic number is 11 which means it is the 11th member (by mass) on the periodic table. The other 2 are oxygen and hydrogen. So Oxygen has an atomic mass of 16 and Hydrogen has an atomic mass of 1.
Oxygen is number 8 on the periodic table and hydrogen is number 1.
Molecular Mass
Na = 23
O = 16
H = 1
Total 40, just as the answer key says. I've probably given you more than you wanted to know, but if you still have trouble, leave a note.
Answer:
380.5g/mol
Explanation:
The molar mass of a compound can be obtained by adding the molar masses of the elements present in the compound.
The molar mass of Cu3(PO4)2 can be obtained as follow:
Molar Mass of Cu = 63.5g/mol
Molar Mass of P = 31g/mol
Molar Mass of O = 16g/mol
The molar mass of Cu3(PO4)2 = (63.5x3) + 2[31 + (16x4)] = 190.5 + 2[31 + 64] = 190.5 + 2[95] = 190.5 + 190 = 380.5g/mol
B. Theory
The hypothesis that stand the test of time (often tested and never rejected) is called theory. A theory is supported by a great dealcof evidence.