☃️ Chemical formulae ➝ 
How to find?
For solving this question, We need to know how to find moles of solution or any substance if a certain weight is given.
Solution:
❍ Molecular weight of
= 2 × 126.90
= 253.80
= 254 (approx.)
❍ Given weight: 12.7
Then, no. of moles,
⇛ No. of moles = 12.7 / 254
⇛ No. of moles = 0.05 moles
⚘ No. of moles of Iodine molecule in the given weight = <u>0.05</u><u> </u><u>moles </u>
<u>━━━━━━━━━━━━━━━━━━━━</u>
You need the molercular mass of Sucrose.
You can either search the molecular formula of Sucrose and calculate the molecular mass, or search directly the molecular mass.
Here you have both:
Molecular mass of sucrose: 342.30 g / mol
Chemical formula of sucrose: C12 H22 O11 (if you want to just must multiply the number of each atom by its atomic mass to get the molecular mass).
Calculate the number of grams of O in that molecule:
O: 11 * 16.00 g/mol = 176.0 g of O.
Now use proportions:
176 g O / 342.30 g sucrose = x / 50.00 g sucrose
=> x = 50.00 g sucrose * 176.0 g O / 342.30 g sucrose =25.71 g O.
Answer: 25.17 g
There is 18 + 633= 651 grams of HCl in aqueous form depending how the reaction is done
Answer:
b. SF₆
Explanation:
Graham's law states that the rate of diffusion of a gas is inversely proportional to the square root of its molecular mass,
As molecular mass of O₂ is 32g/mol, the diffusion is equal to (Assuming constant of proportionality of 1):
1/√32 = 0,1768.
As this diffusion is 2,14 times faster than diffusion of the unknown gas, diffusion of the unknown gas is:
0,1768/2,14 = 0,0826
Know, this diffusion times √molec. mass of the unknown gas must be 1.
That is:
0,0826 = 1/√molec. mass
0,0826√molec. mass = 1
√molec. mass = 12,1
molecular mass of the unknown gas is: 12,1² = <em>146g/mol</em>
Cl₂ has a molecular mass of 70,9 g/mol; SF₆ of <em>146g/mol</em>; kr of 83,8g/mol; UF₆ of 352 g/mol and Xe of 131,3
That means the uknown gas is:
b. SF₆
I hope it helps!
