Response:
22.9 moles (Option 5)
Clarification:
A substance being 35.7% carbon by mass signifies that in every 100 g of the substance, there is 35.7 g of carbon.
Using a rule of three, we get:
100 g of substance ___ has __ 35.7 g of C
769 g of substance ___ has ___ ( 769.35.7) / 100 = 274.5 g of C
1 mol of C = 12 g/m
Mass / Molar mass = Moles
274.5 g / 12 g/m = 22.9 moles
Greetings,
The number of lone pairs of electrons in a C2O molecule is...
4
Each Oxygen atom forms two bonds with Carbon.
I hope this was useful!
-Char
1) To find the molar mass of C6H8O6, you must refer to the atomic weights of C, H, and O from the periodic table: C is 12; H is 1; O is 16 <span> (12x6)+(1x8)+(16x6)= 176g/mol
</span> <span> 176 g = 1 mol
0.5 g = x mol = 500 mg = 0.5 grams
Molar mass = mass ÷ moles
176 = 0.5 ÷ x
x = 2.84 x 10⁻³ mol
2) To calculate the total number of molecules in those </span> 2.84 x 10⁻³ mol, multiply the moles by <span> Avogadro's constant.
Number of molecules = Avogadro's constant x number of moles
Number of molecules = 6.022 x 10²³ x 2.84 x 10⁻³ </span> = 1.71 x 10²¹ molecules of vitamin C. <span>
</span>
Halogens are characterized as a group of 7 on the periodic table. Each of these elements has 7 valence electrons, needing just one additional electron to fill their outer shell, resulting in their high reactivity. Moreover, the periodic law indicates that when the elements are arranged by increasing atomic number, similar patterns in their properties emerge. Thus, halogens exhibit comparable behaviors during chemical reactions with one another, which is indeed accurate.
